SCHEDULE III REAL ESTATE AND ACCUMULATED DEPRECIATION (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2017 USD ($) apartment	Dec. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)	Dec. 31, 2017 USD ($) ft²
Real Estate and Accumulated Depreciation [Line Items]
Encumbrance				$ 2,008,417
Initial cost [Abstract]
Land				2,660,937
Buildings and improvements				9,015,672
Costs capitalized subsequent to acquisition				1,672,222
Gross amount carried at close of period [Abstract]
Land and improvements				2,719,064
Buildings and improvements				10,629,767
Total	$ 13,348,831			13,348,831
Accumulated depreciation	(2,311,546)	$ (1,949,892)	$ (1,564,806)	(2,769,297)
Aggregate cost for federal income tax purpose	10,600,000
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Acquisition, development, and improvement of real estate	700,892	609,669	1,333,102
Disposition of real estate	(28,367)	(264,832)	(246,314)
Balance at the end of year	13,348,831
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at beginning of year	2,311,546	1,949,892	1,564,806
Depreciation expense	464,043	432,165	402,687
Depreciation expense - Disposals and other	(6,292)	(70,511)	(17,601)
Balance at the end of year	$ 2,769,297	2,311,546	1,949,892
Encumbered Apartment Communities [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	14,988
Encumbrance				2,008,417
Initial cost [Abstract]
Land				764,224
Buildings and improvements				2,416,739
Costs capitalized subsequent to acquisition				510,489
Gross amount carried at close of period [Abstract]
Land and improvements				774,421
Buildings and improvements				2,917,031
Total	$ 3,691,452			3,691,452
Accumulated depreciation	(868,971)			(868,971)
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	3,691,452
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 868,971
Encumbered Apartment Communities [Member] | Avondale at Warner Center [Member] | Woodland Hills, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	446
Encumbrance				42,844
Initial cost [Abstract]
Land				10,536
Buildings and improvements				24,522
Costs capitalized subsequent to acquisition				21,096
Gross amount carried at close of period [Abstract]
Land and improvements				10,601
Buildings and improvements				45,553
Total	$ 56,154			56,154
Accumulated depreciation	$ (30,410)			(30,410)
Date of construction	1970
Date acquired	Jan-99
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 56,154
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 30,410
Encumbered Apartment Communities [Member] | Avondale at Warner Center [Member] | Woodland Hills, CA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	3 years
Encumbered Apartment Communities [Member] | Avondale at Warner Center [Member] | Woodland Hills, CA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Encumbered Apartment Communities [Member] | Bel Air [Member] | San Ramon, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	462
Encumbrance				50,386
Initial cost [Abstract]
Land				12,105
Buildings and improvements				18,252
Costs capitalized subsequent to acquisition				35,236
Gross amount carried at close of period [Abstract]
Land and improvements				12,682
Buildings and improvements				52,911
Total	$ 65,593			65,593
Accumulated depreciation	$ (33,713)			(33,713)
Date of construction	1988
Date acquired	Jan-95
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 65,593
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 33,713
Encumbered Apartment Communities [Member] | Bel Air [Member] | San Ramon, CA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	3 years
Encumbered Apartment Communities [Member] | Bel Air [Member] | San Ramon, CA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Encumbered Apartment Communities [Member] | Belcarra [Member] | Bellevue, WA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	296
Encumbrance				50,337
Initial cost [Abstract]
Land				21,725
Buildings and improvements				92,091
Costs capitalized subsequent to acquisition				1,266
Gross amount carried at close of period [Abstract]
Land and improvements				21,725
Buildings and improvements				93,357
Total	$ 115,082			115,082
Accumulated depreciation	$ (12,712)			(12,712)
Date of construction	2009
Date acquired	Apr-14
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 115,082
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 12,712
Encumbered Apartment Communities [Member] | Belcarra [Member] | Bellevue, WA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	5 years
Encumbered Apartment Communities [Member] | Belcarra [Member] | Bellevue, WA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Encumbered Apartment Communities [Member] | BellCentre [Member] | Bellevue, WA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	248
Encumbrance				38,024
Initial cost [Abstract]
Land				16,197
Buildings and improvements				67,207
Costs capitalized subsequent to acquisition				3,529
Gross amount carried at close of period [Abstract]
Land and improvements				16,197
Buildings and improvements				70,736
Total	$ 86,933			86,933
Accumulated depreciation	$ (10,053)			(10,053)
Date of construction	2001
Date acquired	Apr-14
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 86,933
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 10,053
Encumbered Apartment Communities [Member] | BellCentre [Member] | Bellevue, WA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	5 years
Encumbered Apartment Communities [Member] | BellCentre [Member] | Bellevue, WA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Encumbered Apartment Communities [Member] | Belmont Station [Member] | Los Angeles, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	275
Encumbrance				29,654
Initial cost [Abstract]
Land				8,100
Buildings and improvements				66,666
Costs capitalized subsequent to acquisition				6,176
Gross amount carried at close of period [Abstract]
Land and improvements				8,267
Buildings and improvements				72,675
Total	$ 80,942			80,942
Accumulated depreciation	$ (26,071)			(26,071)
Date of construction	2009
Date acquired	Mar-09
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 80,942
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 26,071
Encumbered Apartment Communities [Member] | Belmont Station [Member] | Los Angeles, CA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	3 years
Encumbered Apartment Communities [Member] | Belmont Station [Member] | Los Angeles, CA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Encumbered Apartment Communities [Member] | Brookside Oaks [Member] | Sunnyvale, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	170
Encumbrance				18,152
Initial cost [Abstract]
Land				7,301
Buildings and improvements				16,310
Costs capitalized subsequent to acquisition				25,695
Gross amount carried at close of period [Abstract]
Land and improvements				10,328
Buildings and improvements				38,978
Total	$ 49,306			49,306
Accumulated depreciation	$ (20,377)			(20,377)
Date of construction	1973
Date acquired	Jun-00
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 49,306
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 20,377
Encumbered Apartment Communities [Member] | Brookside Oaks [Member] | Sunnyvale, CA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	3 years
Encumbered Apartment Communities [Member] | Brookside Oaks [Member] | Sunnyvale, CA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Encumbered Apartment Communities [Member] | Carmel Creek [Member] | San Diego, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	348
Encumbrance				61,009
Initial cost [Abstract]
Land				26,842
Buildings and improvements				107,368
Costs capitalized subsequent to acquisition				5,271
Gross amount carried at close of period [Abstract]
Land and improvements				26,842
Buildings and improvements				112,639
Total	$ 139,481			139,481
Accumulated depreciation	$ (16,153)			(16,153)
Date of construction	2000
Date acquired	Apr-14
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 139,481
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 16,153
Encumbered Apartment Communities [Member] | Carmel Creek [Member] | San Diego, CA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	5 years
Encumbered Apartment Communities [Member] | Carmel Creek [Member] | San Diego, CA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Encumbered Apartment Communities [Member] | City View [Member] | Hayward, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	572
Encumbrance				64,094
Initial cost [Abstract]
Land				9,883
Buildings and improvements				37,670
Costs capitalized subsequent to acquisition				26,670
Gross amount carried at close of period [Abstract]
Land and improvements				10,350
Buildings and improvements				63,873
Total	$ 74,223			74,223
Accumulated depreciation	$ (44,300)			(44,300)
Date of construction	1975
Date acquired	Mar-98
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 74,223
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 44,300
Encumbered Apartment Communities [Member] | City View [Member] | Hayward, CA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	3 years
Encumbered Apartment Communities [Member] | City View [Member] | Hayward, CA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Encumbered Apartment Communities [Member] | Courtyard off Main [Member] | Bellevue, WA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	110
Encumbrance				14,846
Initial cost [Abstract]
Land				7,465
Buildings and improvements				21,405
Costs capitalized subsequent to acquisition				3,757
Gross amount carried at close of period [Abstract]
Land and improvements				7,465
Buildings and improvements				25,162
Total	$ 32,627			32,627
Accumulated depreciation	$ (6,700)			(6,700)
Date of construction	2000
Date acquired	Oct-10
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 32,627
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 6,700
Encumbered Apartment Communities [Member] | Courtyard off Main [Member] | Bellevue, WA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	3 years
Encumbered Apartment Communities [Member] | Courtyard off Main [Member] | Bellevue, WA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Encumbered Apartment Communities [Member] | Domaine [Member] | Seattle, WA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	92
Encumbrance				14,029
Initial cost [Abstract]
Land				9,059
Buildings and improvements				27,177
Costs capitalized subsequent to acquisition				920
Gross amount carried at close of period [Abstract]
Land and improvements				9,059
Buildings and improvements				28,097
Total	$ 37,156			37,156
Accumulated depreciation	$ (5,183)			(5,183)
Date of construction	2009
Date acquired	Sep-12
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 37,156
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 5,183
Encumbered Apartment Communities [Member] | Domaine [Member] | Seattle, WA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	3 years
Encumbered Apartment Communities [Member] | Domaine [Member] | Seattle, WA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Encumbered Apartment Communities [Member] | Elevation [Member] | Redmond, WA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	158
Encumbrance				10,406
Initial cost [Abstract]
Land				4,758
Buildings and improvements				14,285
Costs capitalized subsequent to acquisition				6,476
Gross amount carried at close of period [Abstract]
Land and improvements				4,757
Buildings and improvements				20,762
Total	$ 25,519			25,519
Accumulated depreciation	$ (7,508)			(7,508)
Date of construction	1986
Date acquired	Jun-10
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 25,519
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 7,508
Encumbered Apartment Communities [Member] | Elevation [Member] | Redmond, WA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	3 years
Encumbered Apartment Communities [Member] | Elevation [Member] | Redmond, WA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Encumbered Apartment Communities [Member] | Ellington [Member] | Bellevue, WA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	220
Encumbrance				20,684
Initial cost [Abstract]
Land				15,066
Buildings and improvements				45,249
Costs capitalized subsequent to acquisition				3,191
Gross amount carried at close of period [Abstract]
Land and improvements				15,066
Buildings and improvements				48,440
Total	$ 63,506			63,506
Accumulated depreciation	$ (5,793)			(5,793)
Date of construction	1994
Date acquired	Jul-14
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 63,506
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 5,793
Encumbered Apartment Communities [Member] | Ellington [Member] | Bellevue, WA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	3 years
Encumbered Apartment Communities [Member] | Ellington [Member] | Bellevue, WA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Encumbered Apartment Communities [Member] | Fairhaven Apartments [Member] | Santa Ana, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	164
Encumbrance				18,533
Initial cost [Abstract]
Land				2,626
Buildings and improvements				10,485
Costs capitalized subsequent to acquisition				7,741
Gross amount carried at close of period [Abstract]
Land and improvements				2,957
Buildings and improvements				17,895
Total	$ 20,852			20,852
Accumulated depreciation	$ (9,600)			(9,600)
Date of construction	1970
Date acquired	Nov-01
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 20,852
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 9,600
Encumbered Apartment Communities [Member] | Fairhaven Apartments [Member] | Santa Ana, CA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	3 years
Encumbered Apartment Communities [Member] | Fairhaven Apartments [Member] | Santa Ana, CA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Encumbered Apartment Communities [Member] | Form 15 [Member] | San Diego, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	242
Encumbrance				46,189
Initial cost [Abstract]
Land				24,510
Buildings and improvements				72,221
Costs capitalized subsequent to acquisition				4,734
Gross amount carried at close of period [Abstract]
Land and improvements				25,540
Buildings and improvements				75,925
Total	$ 101,465			101,465
Accumulated depreciation	$ (4,850)			(4,850)
Date of construction	2014
Date acquired	Mar-16
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 101,465
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 4,850
Encumbered Apartment Communities [Member] | Form 15 [Member] | San Diego, CA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	3 years
Encumbered Apartment Communities [Member] | Form 15 [Member] | San Diego, CA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Encumbered Apartment Communities [Member] | Foster's Landing [Member] | Foster City, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	490
Encumbrance				93,585
Initial cost [Abstract]
Land				61,714
Buildings and improvements				144,000
Costs capitalized subsequent to acquisition				8,245
Gross amount carried at close of period [Abstract]
Land and improvements				61,714
Buildings and improvements				152,245
Total	$ 213,959			213,959
Accumulated depreciation	$ (22,269)			(22,269)
Date of construction	1987
Date acquired	Apr-14
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 213,959
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 22,269
Encumbered Apartment Communities [Member] | Foster's Landing [Member] | Foster City, CA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	5 years
Encumbered Apartment Communities [Member] | Foster's Landing [Member] | Foster City, CA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Encumbered Apartment Communities [Member] | Fountain At Riveroaks [Member] | San Jose, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	226
Encumbrance				31,056
Initial cost [Abstract]
Land				26,046
Buildings and improvements				60,773
Costs capitalized subsequent to acquisition				3,652
Gross amount carried at close of period [Abstract]
Land and improvements				26,046
Buildings and improvements				64,425
Total	$ 90,471			90,471
Accumulated depreciation	$ (9,116)			(9,116)
Date of construction	1990
Date acquired	Apr-14
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 90,471
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 9,116
Encumbered Apartment Communities [Member] | Fountain At Riveroaks [Member] | San Jose, CA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	3 years
Encumbered Apartment Communities [Member] | Fountain At Riveroaks [Member] | San Jose, CA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Encumbered Apartment Communities [Member] | Fountain Park [Member] | Playa Vista, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	705
Encumbrance				82,503
Initial cost [Abstract]
Land				25,073
Buildings and improvements				94,980
Costs capitalized subsequent to acquisition				31,832
Gross amount carried at close of period [Abstract]
Land and improvements				25,203
Buildings and improvements				126,682
Total	$ 151,885			151,885
Accumulated depreciation	$ (65,049)			(65,049)
Date of construction	2002
Date acquired	Feb-04
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 151,885
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 65,049
Encumbered Apartment Communities [Member] | Fountain Park [Member] | Playa Vista, CA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	3 years
Encumbered Apartment Communities [Member] | Fountain Park [Member] | Playa Vista, CA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Encumbered Apartment Communities [Member] | Hidden Valley [Member] | Simi Valley, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	324
Encumbrance				29,327
Initial cost [Abstract]
Land				14,174
Buildings and improvements				34,065
Costs capitalized subsequent to acquisition				4,607
Gross amount carried at close of period [Abstract]
Land and improvements				9,674
Buildings and improvements				43,172
Total	$ 52,846			52,846
Accumulated depreciation	$ (19,168)			(19,168)
Date of construction	2004
Date acquired	Dec-04
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 52,846
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 19,168
Encumbered Apartment Communities [Member] | Hidden Valley [Member] | Simi Valley, CA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	3 years
Encumbered Apartment Communities [Member] | Hidden Valley [Member] | Simi Valley, CA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Encumbered Apartment Communities [Member] | Highlands at Wynhaven [Member] | Issaquah, WA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	333
Encumbrance				30,240
Initial cost [Abstract]
Land				16,271
Buildings and improvements				48,932
Costs capitalized subsequent to acquisition				12,255
Gross amount carried at close of period [Abstract]
Land and improvements				16,271
Buildings and improvements				61,187
Total	$ 77,458			77,458
Accumulated depreciation	$ (21,289)			(21,289)
Date of construction	2000
Date acquired	Aug-08
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 77,458
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 21,289
Encumbered Apartment Communities [Member] | Highlands at Wynhaven [Member] | Issaquah, WA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	3 years
Encumbered Apartment Communities [Member] | Highlands at Wynhaven [Member] | Issaquah, WA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Encumbered Apartment Communities [Member] | Highridge [Member] | Rancho Palos Verdes, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	255
Encumbrance				69,238
Initial cost [Abstract]
Land				5,419
Buildings and improvements				18,347
Costs capitalized subsequent to acquisition				30,726
Gross amount carried at close of period [Abstract]
Land and improvements				6,073
Buildings and improvements				48,419
Total	$ 54,492			54,492
Accumulated depreciation	$ (33,537)			(33,537)
Date of construction	1972
Date acquired	May-97
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 54,492
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 33,537
Encumbered Apartment Communities [Member] | Highridge [Member] | Rancho Palos Verdes, CA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	3 years
Encumbered Apartment Communities [Member] | Highridge [Member] | Rancho Palos Verdes, CA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Encumbered Apartment Communities [Member] | Hillcrest Park [Member] | Newbury Park, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	608
Encumbrance				62,780
Initial cost [Abstract]
Land				15,318
Buildings and improvements				40,601
Costs capitalized subsequent to acquisition				19,704
Gross amount carried at close of period [Abstract]
Land and improvements				15,755
Buildings and improvements				59,868
Total	$ 75,623			75,623
Accumulated depreciation	$ (37,377)			(37,377)
Date of construction	1973
Date acquired	Mar-98
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 75,623
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 37,377
Encumbered Apartment Communities [Member] | Hillcrest Park [Member] | Newbury Park, CA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	3 years
Encumbered Apartment Communities [Member] | Hillcrest Park [Member] | Newbury Park, CA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Encumbered Apartment Communities [Member] | Huntington Breakers [Member] | Huntington Beach, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	342
Encumbrance				35,192
Initial cost [Abstract]
Land				9,306
Buildings and improvements				22,720
Costs capitalized subsequent to acquisition				20,267
Gross amount carried at close of period [Abstract]
Land and improvements				9,315
Buildings and improvements				42,978
Total	$ 52,293			52,293
Accumulated depreciation	$ (25,931)			(25,931)
Date of construction	1984
Date acquired	Oct-97
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 52,293
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 25,931
Encumbered Apartment Communities [Member] | Huntington Breakers [Member] | Huntington Beach, CA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	3 years
Encumbered Apartment Communities [Member] | Huntington Breakers [Member] | Huntington Beach, CA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Encumbered Apartment Communities [Member] | Inglenook Court [Member] | Bothell, WA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	224
Encumbrance				8,216
Initial cost [Abstract]
Land				3,467
Buildings and improvements				7,881
Costs capitalized subsequent to acquisition				7,588
Gross amount carried at close of period [Abstract]
Land and improvements				3,474
Buildings and improvements				15,462
Total	$ 18,936			18,936
Accumulated depreciation	$ (12,067)			(12,067)
Date of construction	1985
Date acquired	Oct-94
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 18,936
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 12,067
Encumbered Apartment Communities [Member] | Inglenook Court [Member] | Bothell, WA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	3 years
Encumbered Apartment Communities [Member] | Inglenook Court [Member] | Bothell, WA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Encumbered Apartment Communities [Member] | 1000 Kiely [Member] | Santa Clara, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	121
Encumbrance				34,868
Initial cost [Abstract]
Land				9,359
Buildings and improvements				21,845
Costs capitalized subsequent to acquisition				7,652
Gross amount carried at close of period [Abstract]
Land and improvements				9,359
Buildings and improvements				29,497
Total	$ 38,856			38,856
Accumulated depreciation	$ (8,954)			(8,954)
Date of construction	1971
Date acquired	Mar-11
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 38,856
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 8,954
Encumbered Apartment Communities [Member] | Magnolia Square/Magnolia Lane [Member] | Sunnyvale, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	188
Encumbrance				52,205
Initial cost [Abstract]
Land				8,190
Buildings and improvements				24,736
Costs capitalized subsequent to acquisition				16,649
Gross amount carried at close of period [Abstract]
Land and improvements				8,191
Buildings and improvements				41,384
Total	$ 49,575			49,575
Accumulated depreciation	$ (18,214)			(18,214)
Date of construction	1963
Date acquired	Sep-07
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 49,575
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 18,214
Encumbered Apartment Communities [Member] | Magnolia Square/Magnolia Lane [Member] | Sunnyvale, CA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	3 years
Encumbered Apartment Communities [Member] | Magnolia Square/Magnolia Lane [Member] | Sunnyvale, CA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Encumbered Apartment Communities [Member] | Mill Creek at Windermere [Member] | San Ramon, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	400
Encumbrance				45,419
Initial cost [Abstract]
Land				29,551
Buildings and improvements				69,032
Costs capitalized subsequent to acquisition				4,700
Gross amount carried at close of period [Abstract]
Land and improvements				29,551
Buildings and improvements				73,732
Total	$ 103,283			103,283
Accumulated depreciation	$ (26,212)			(26,212)
Date of construction	2005
Date acquired	Sep-07
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 103,283
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 26,212
Encumbered Apartment Communities [Member] | Mill Creek at Windermere [Member] | San Ramon, CA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	3 years
Encumbered Apartment Communities [Member] | Mill Creek at Windermere [Member] | San Ramon, CA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Encumbered Apartment Communities [Member] | Mirabella [Member] | Marina Del Rey, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	188
Encumbrance				41,509
Initial cost [Abstract]
Land				6,180
Buildings and improvements				26,673
Costs capitalized subsequent to acquisition				14,952
Gross amount carried at close of period [Abstract]
Land and improvements				6,270
Buildings and improvements				41,535
Total	$ 47,805			47,805
Accumulated depreciation	$ (22,805)			(22,805)
Date of construction	2000
Date acquired	May-00
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 47,805
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 22,805
Encumbered Apartment Communities [Member] | Mirabella [Member] | Marina Del Rey, CA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	3 years
Encumbered Apartment Communities [Member] | Mirabella [Member] | Marina Del Rey, CA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Encumbered Apartment Communities [Member] | Montarosa [Member] | San Diego, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	472
Encumbrance				61,222
Initial cost [Abstract]
Land				26,697
Buildings and improvements				106,787
Costs capitalized subsequent to acquisition				4,611
Gross amount carried at close of period [Abstract]
Land and improvements				26,697
Buildings and improvements				111,398
Total	$ 138,095			138,095
Accumulated depreciation	$ (15,660)			(15,660)
Date of construction	1990
Date acquired	Apr-14
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 138,095
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 15,660
Encumbered Apartment Communities [Member] | Montarosa [Member] | San Diego, CA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	5 years
Encumbered Apartment Communities [Member] | Montarosa [Member] | San Diego, CA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Encumbered Apartment Communities [Member] | Montclaire [Member] | Sunnyvale, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	390
Encumbrance				43,261
Initial cost [Abstract]
Land				4,842
Buildings and improvements				19,776
Costs capitalized subsequent to acquisition				24,901
Gross amount carried at close of period [Abstract]
Land and improvements				4,997
Buildings and improvements				44,522
Total	$ 49,519			49,519
Accumulated depreciation	$ (37,862)			(37,862)
Date of construction	1973
Date acquired	Dec-88
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 49,519
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 37,862
Encumbered Apartment Communities [Member] | Montclaire [Member] | Sunnyvale, CA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	3 years
Encumbered Apartment Communities [Member] | Montclaire [Member] | Sunnyvale, CA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Encumbered Apartment Communities [Member] | Montebello [Member] | Kirkland, WA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	248
Encumbrance				25,569
Initial cost [Abstract]
Land				13,857
Buildings and improvements				41,575
Costs capitalized subsequent to acquisition				4,524
Gross amount carried at close of period [Abstract]
Land and improvements				13,858
Buildings and improvements				46,098
Total	$ 59,956			59,956
Accumulated depreciation	$ (9,729)			(9,729)
Date of construction	1996
Date acquired	Jul-12
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 59,956
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 9,729
Encumbered Apartment Communities [Member] | Montebello [Member] | Kirkland, WA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	3 years
Encumbered Apartment Communities [Member] | Montebello [Member] | Kirkland, WA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Encumbered Apartment Communities [Member] | Montejo Apartments [Member] | Garden Grove, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	124
Encumbrance				13,196
Initial cost [Abstract]
Land				1,925
Buildings and improvements				7,685
Costs capitalized subsequent to acquisition				3,871
Gross amount carried at close of period [Abstract]
Land and improvements				2,194
Buildings and improvements				11,287
Total	$ 13,481			13,481
Accumulated depreciation	$ (5,901)			(5,901)
Date of construction	1974
Date acquired	Nov-01
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 13,481
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 5,901
Encumbered Apartment Communities [Member] | Montejo Apartments [Member] | Garden Grove, CA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	3 years
Encumbered Apartment Communities [Member] | Montejo Apartments [Member] | Garden Grove, CA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Encumbered Apartment Communities [Member] | Park Highland [Member] | Bellevue, WA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	250
Encumbrance				25,910
Initial cost [Abstract]
Land				9,391
Buildings and improvements				38,224
Costs capitalized subsequent to acquisition				11,622
Gross amount carried at close of period [Abstract]
Land and improvements				9,391
Buildings and improvements				49,846
Total	$ 59,237			59,237
Accumulated depreciation	$ (8,048)			(8,048)
Date of construction	1993
Date acquired	Apr-14
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 59,237
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 8,048
Encumbered Apartment Communities [Member] | Park Highland [Member] | Bellevue, WA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	5 years
Encumbered Apartment Communities [Member] | Park Highland [Member] | Bellevue, WA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Encumbered Apartment Communities [Member] | Park Hill at Issaquah [Member] | Issaquah, WA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	245
Encumbrance				26,607
Initial cost [Abstract]
Land				7,284
Buildings and improvements				21,937
Costs capitalized subsequent to acquisition				7,460
Gross amount carried at close of period [Abstract]
Land and improvements				7,284
Buildings and improvements				29,397
Total	$ 36,681			36,681
Accumulated depreciation	$ (13,241)			(13,241)
Date of construction	1999
Date acquired	Feb-99
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 36,681
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 13,241
Encumbered Apartment Communities [Member] | Park Hill at Issaquah [Member] | Issaquah, WA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	3 years
Encumbered Apartment Communities [Member] | Park Hill at Issaquah [Member] | Issaquah, WA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Encumbered Apartment Communities [Member] | Pinnacle at Fullerton [Member] | Fullerton, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	192
Encumbrance				26,094
Initial cost [Abstract]
Land				11,019
Buildings and improvements				45,932
Costs capitalized subsequent to acquisition				2,707
Gross amount carried at close of period [Abstract]
Land and improvements				11,019
Buildings and improvements				48,639
Total	$ 59,658			59,658
Accumulated depreciation	$ (6,843)			(6,843)
Date of construction	2004
Date acquired	Apr-14
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 59,658
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 6,843
Encumbered Apartment Communities [Member] | Pinnacle at Fullerton [Member] | Fullerton, CA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	5 years
Encumbered Apartment Communities [Member] | Pinnacle at Fullerton [Member] | Fullerton, CA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Encumbered Apartment Communities [Member] | Pinnacle on Lake Washington [Member] | Renton, WA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	180
Encumbrance				17,794
Initial cost [Abstract]
Land				7,760
Buildings and improvements				31,041
Costs capitalized subsequent to acquisition				1,880
Gross amount carried at close of period [Abstract]
Land and improvements				7,760
Buildings and improvements				32,921
Total	$ 40,681			40,681
Accumulated depreciation	$ (4,530)			(4,530)
Date of construction	2001
Date acquired	Apr-14
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 40,681
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 4,530
Encumbered Apartment Communities [Member] | Pinnacle on Lake Washington [Member] | Renton, WA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	5 years
Encumbered Apartment Communities [Member] | Pinnacle on Lake Washington [Member] | Renton, WA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Encumbered Apartment Communities [Member] | Pinnacle at MacArthur Ranch [Member] | Santa Ana, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	253
Encumbrance				37,726
Initial cost [Abstract]
Land				15,810
Buildings and improvements				66,401
Costs capitalized subsequent to acquisition				4,039
Gross amount carried at close of period [Abstract]
Land and improvements				15,810
Buildings and improvements				70,440
Total	$ 86,250			86,250
Accumulated depreciation	$ (9,747)			(9,747)
Date of construction	2002
Date acquired	Apr-14
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 86,250
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 9,747
Encumbered Apartment Communities [Member] | Pinnacle at MacArthur Ranch [Member] | Santa Ana, CA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	5 years
Encumbered Apartment Communities [Member] | Pinnacle at MacArthur Ranch [Member] | Santa Ana, CA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Encumbered Apartment Communities [Member] | Pinnacle at Otay Ranch I & II [Member] | Chula Vista, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	364
Encumbrance				38,649
Initial cost [Abstract]
Land				17,023
Buildings and improvements				68,093
Costs capitalized subsequent to acquisition				3,245
Gross amount carried at close of period [Abstract]
Land and improvements				17,023
Buildings and improvements				71,338
Total	$ 88,361			88,361
Accumulated depreciation	$ (10,033)			(10,033)
Date of construction	2001
Date acquired	Apr-14
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 88,361
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 10,033
Encumbered Apartment Communities [Member] | Pinnacle at Otay Ranch I & II [Member] | Chula Vista, CA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	5 years
Encumbered Apartment Communities [Member] | Pinnacle at Otay Ranch I & II [Member] | Chula Vista, CA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Encumbered Apartment Communities [Member] | Pinnacle at Talega [Member] | San Clemente, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	362
Encumbrance				43,166
Initial cost [Abstract]
Land				19,292
Buildings and improvements				77,168
Costs capitalized subsequent to acquisition				2,228
Gross amount carried at close of period [Abstract]
Land and improvements				19,292
Buildings and improvements				79,396
Total	$ 98,688			98,688
Accumulated depreciation	$ (11,091)			(11,091)
Date of construction	2002
Date acquired	Apr-14
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 98,688
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 11,091
Encumbered Apartment Communities [Member] | Pinnacle at Talega [Member] | Irvine, CA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	5 years
Encumbered Apartment Communities [Member] | Pinnacle at Talega [Member] | Irvine, CA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Encumbered Apartment Communities [Member] | Membership Interest In Sage At Cupertino [Member] | San Jose, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	230
Encumbrance				51,938
Initial cost [Abstract]
Land				35,719
Buildings and improvements				53,449
Costs capitalized subsequent to acquisition				1,495
Gross amount carried at close of period [Abstract]
Land and improvements				35,719
Buildings and improvements				54,944
Total	$ 90,663			90,663
Accumulated depreciation	$ (1,457)			(1,457)
Date of construction	1971
Date acquired	Mar-17
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 90,663
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 1,457
Encumbered Apartment Communities [Member] | Membership Interest In Sage At Cupertino [Member] | San Jose, CA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	3 years
Encumbered Apartment Communities [Member] | Membership Interest In Sage At Cupertino [Member] | San Jose, CA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Encumbered Apartment Communities [Member] | Stevenson Place [Member] | Fremont, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	200
Encumbrance				20,247
Initial cost [Abstract]
Land				996
Buildings and improvements				5,582
Costs capitalized subsequent to acquisition				11,717
Gross amount carried at close of period [Abstract]
Land and improvements				1,001
Buildings and improvements				17,294
Total	$ 18,295			18,295
Accumulated depreciation	$ (12,155)			(12,155)
Date of construction	1975
Date acquired	Apr-00
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 18,295
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 12,155
Encumbered Apartment Communities [Member] | Stevenson Place [Member] | Fremont, CA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	3 years
Encumbered Apartment Communities [Member] | Stevenson Place [Member] | Fremont, CA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Encumbered Apartment Communities [Member] | Summerhill Park [Member] | Sunnyvale, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	100
Encumbrance				12,538
Initial cost [Abstract]
Land				2,654
Buildings and improvements				4,918
Costs capitalized subsequent to acquisition				10,949
Gross amount carried at close of period [Abstract]
Land and improvements				2,656
Buildings and improvements				15,865
Total	$ 18,521			18,521
Accumulated depreciation	$ (8,777)			(8,777)
Date of construction	1988
Date acquired	Sep-88
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 18,521
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 8,777
Encumbered Apartment Communities [Member] | Summerhill Park [Member] | Sunnyvale, CA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	3 years
Encumbered Apartment Communities [Member] | Summerhill Park [Member] | Sunnyvale, CA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Encumbered Apartment Communities [Member] | The Audrey at Belltown [Member] | Seattle, WA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	137
Encumbrance				20,521
Initial cost [Abstract]
Land				9,228
Buildings and improvements				36,911
Costs capitalized subsequent to acquisition				778
Gross amount carried at close of period [Abstract]
Land and improvements				9,228
Buildings and improvements				37,689
Total	$ 46,917			46,917
Accumulated depreciation	$ (5,163)			(5,163)
Date of construction	1992
Date acquired	Apr-14
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 46,917
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 5,163
Encumbered Apartment Communities [Member] | The Audrey at Belltown [Member] | Seattle, WA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	5 years
Encumbered Apartment Communities [Member] | The Audrey at Belltown [Member] | Seattle, WA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Encumbered Apartment Communities [Member] | The Barkley [Member] | Anaheim, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	161
Encumbrance				15,358
Initial cost [Abstract]
Land				0
Buildings and improvements				8,520
Costs capitalized subsequent to acquisition				6,515
Gross amount carried at close of period [Abstract]
Land and improvements				2,353
Buildings and improvements				12,682
Total	$ 15,035			15,035
Accumulated depreciation	$ (7,483)			(7,483)
Date of construction	1984
Date acquired	Apr-00
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 15,035
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 7,483
Encumbered Apartment Communities [Member] | The Barkley [Member] | Anaheim, CA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	3 years
Encumbered Apartment Communities [Member] | The Barkley [Member] | Anaheim, CA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Encumbered Apartment Communities [Member] | The Bernard [Member] | Seattle, WA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	63
Encumbrance				8,531
Initial cost [Abstract]
Land				3,699
Buildings and improvements				11,345
Costs capitalized subsequent to acquisition				584
Gross amount carried at close of period [Abstract]
Land and improvements				3,689
Buildings and improvements				11,939
Total	$ 15,628			15,628
Accumulated depreciation	$ (2,587)			(2,587)
Date of construction	2008
Date acquired	Sep-11
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 15,628
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 2,587
Encumbered Apartment Communities [Member] | The Bernard [Member] | Seattle, WA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	3 years
Encumbered Apartment Communities [Member] | The Bernard [Member] | Seattle, WA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Encumbered Apartment Communities [Member] | The Dylan [Member] | West Hollywood, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	184
Encumbrance				59,468
Initial cost [Abstract]
Land				19,984
Buildings and improvements				82,286
Costs capitalized subsequent to acquisition				608
Gross amount carried at close of period [Abstract]
Land and improvements				19,990
Buildings and improvements				82,888
Total	$ 102,878			102,878
Accumulated depreciation	$ (9,097)			(9,097)
Date of construction	2015
Date acquired	Mar-15
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 102,878
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 9,097
Encumbered Apartment Communities [Member] | The Dylan [Member] | West Hollywood, CA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	3 years
Encumbered Apartment Communities [Member] | The Dylan [Member] | West Hollywood, CA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Encumbered Apartment Communities [Member] | The Huntington [Member] | Huntington Beach, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	276
Encumbrance				28,799
Initial cost [Abstract]
Land				10,374
Buildings and improvements				41,495
Costs capitalized subsequent to acquisition				4,741
Gross amount carried at close of period [Abstract]
Land and improvements				10,374
Buildings and improvements				46,236
Total	$ 56,610			56,610
Accumulated depreciation	$ (9,671)			(9,671)
Date of construction	1975
Date acquired	Jun-12
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 56,610
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 9,671
Encumbered Apartment Communities [Member] | The Huntington [Member] | Huntington Beach, CA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	3 years
Encumbered Apartment Communities [Member] | The Huntington [Member] | Huntington Beach, CA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Encumbered Apartment Communities [Member] | The Huxley [Member] | West Hollywood, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	187
Encumbrance				54,155
Initial cost [Abstract]
Land				19,362
Buildings and improvements				75,641
Costs capitalized subsequent to acquisition				1,033
Gross amount carried at close of period [Abstract]
Land and improvements				19,371
Buildings and improvements				76,665
Total	$ 96,036			96,036
Accumulated depreciation	$ (8,608)			(8,608)
Date of construction	2014
Date acquired	Mar-15
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 96,036
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 8,608
Encumbered Apartment Communities [Member] | The Huxley [Member] | West Hollywood, CA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	3 years
Encumbered Apartment Communities [Member] | The Huxley [Member] | West Hollywood, CA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Encumbered Apartment Communities [Member] | The Landing at Jack London Square [Member] | Oakland, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	282
Encumbrance				51,246
Initial cost [Abstract]
Land				33,554
Buildings and improvements				78,292
Costs capitalized subsequent to acquisition				5,314
Gross amount carried at close of period [Abstract]
Land and improvements				33,554
Buildings and improvements				83,606
Total	$ 117,160			117,160
Accumulated depreciation	$ (12,370)			(12,370)
Date of construction	2001
Date acquired	Apr-14
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 117,160
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 12,370
Encumbered Apartment Communities [Member] | The Landing at Jack London Square [Member] | Oakland, CA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	5 years
Encumbered Apartment Communities [Member] | The Landing at Jack London Square [Member] | Oakland, CA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Encumbered Apartment Communities [Member] | The Palisades [Member] | Bellevue, WA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	192
Encumbrance				19,338
Initial cost [Abstract]
Land				1,560
Buildings and improvements				6,242
Costs capitalized subsequent to acquisition				12,709
Gross amount carried at close of period [Abstract]
Land and improvements				1,565
Buildings and improvements				18,946
Total	$ 20,511			20,511
Accumulated depreciation	$ (16,021)			(16,021)
Date of construction	1977
Date acquired	May-90
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 20,511
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 16,021
Encumbered Apartment Communities [Member] | The Palisades [Member] | Bellevue, WA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	3 years
Encumbered Apartment Communities [Member] | The Palisades [Member] | Bellevue, WA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Encumbered Apartment Communities [Member] | The Palms at Laguna Niguel [Member] | Laguna Niguel, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	460
Encumbrance				54,450
Initial cost [Abstract]
Land				23,584
Buildings and improvements				94,334
Costs capitalized subsequent to acquisition				6,569
Gross amount carried at close of period [Abstract]
Land and improvements				23,584
Buildings and improvements				100,903
Total	$ 124,487			124,487
Accumulated depreciation	$ (14,019)			(14,019)
Date of construction	1988
Date acquired	Apr-14
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 124,487
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 14,019
Encumbered Apartment Communities [Member] | The Palms at Laguna Niguel [Member] | Laguna Niguel, CA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	5 years
Encumbered Apartment Communities [Member] | The Palms at Laguna Niguel [Member] | Laguna Niguel, CA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Encumbered Apartment Communities [Member] | The Waterford [Member] | San Jose, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	238
Encumbrance				29,760
Initial cost [Abstract]
Land				11,808
Buildings and improvements				24,500
Costs capitalized subsequent to acquisition				14,581
Gross amount carried at close of period [Abstract]
Land and improvements				15,165
Buildings and improvements				35,724
Total	$ 50,889			50,889
Accumulated depreciation	$ (20,491)			(20,491)
Date of construction	2000
Date acquired	Jun-00
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 50,889
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 20,491
Encumbered Apartment Communities [Member] | The Waterford [Member] | San Jose, CA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	3 years
Encumbered Apartment Communities [Member] | The Waterford [Member] | San Jose, CA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Encumbered Apartment Communities [Member] | Valley Park [Member] | Fountain Valley [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	160
Encumbrance				21,400
Initial cost [Abstract]
Land				3,361
Buildings and improvements				13,420
Costs capitalized subsequent to acquisition				5,744
Gross amount carried at close of period [Abstract]
Land and improvements				3,761
Buildings and improvements				18,764
Total	$ 22,525			22,525
Accumulated depreciation	$ (9,907)			(9,907)
Date of construction	1969
Date acquired	Nov-01
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 22,525
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 9,907
Encumbered Apartment Communities [Member] | Valley Park [Member] | Fountain Valley [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	3 years
Encumbered Apartment Communities [Member] | Valley Park [Member] | Fountain Valley [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Encumbered Apartment Communities [Member] | Villa Angelina [Member] | Placentia, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	256
Encumbrance				27,869
Initial cost [Abstract]
Land				4,498
Buildings and improvements				17,962
Costs capitalized subsequent to acquisition				7,044
Gross amount carried at close of period [Abstract]
Land and improvements				4,962
Buildings and improvements				24,542
Total	$ 29,504			29,504
Accumulated depreciation	$ (13,340)			(13,340)
Date of construction	1970
Date acquired	Nov-01
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 29,504
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 13,340
Encumbered Apartment Communities [Member] | Villa Angelina [Member] | Placentia, CA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	3 years
Encumbered Apartment Communities [Member] | Villa Angelina [Member] | Placentia, CA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Encumbered Apartment Communities [Member] | Villa Grenada [Member] | Santa Clara, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	270
Encumbrance				56,474
Initial cost [Abstract]
Land				38,299
Buildings and improvements				89,365
Costs capitalized subsequent to acquisition				1,449
Gross amount carried at close of period [Abstract]
Land and improvements				38,299
Buildings and improvements				90,814
Total	$ 129,113			129,113
Accumulated depreciation	$ (12,672)			(12,672)
Date of construction	2010
Date acquired	Apr-14
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 129,113
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 12,672
Encumbered Apartment Communities [Member] | Villa Grenada [Member] | Santa Clara, CA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	5 years
Encumbered Apartment Communities [Member] | Villa Grenada [Member] | Santa Clara, CA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Encumbered Apartment Communities [Member] | Wandering Creek [Member] | Kent, WA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	156
Encumbrance				5,239
Initial cost [Abstract]
Land				1,285
Buildings and improvements				4,980
Costs capitalized subsequent to acquisition				4,203
Gross amount carried at close of period [Abstract]
Land and improvements				1,296
Buildings and improvements				9,172
Total	$ 10,468			10,468
Accumulated depreciation	$ (7,166)			(7,166)
Date of construction	1986
Date acquired	Nov-95
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 10,468
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 7,166
Encumbered Apartment Communities [Member] | Wandering Creek [Member] | Kent, WA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	3 years
Encumbered Apartment Communities [Member] | Wandering Creek [Member] | Kent, WA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Encumbered Apartment Communities [Member] | Wilshire Promenade [Member] | Fullerton, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	149
Encumbrance				16,567
Initial cost [Abstract]
Land				3,118
Buildings and improvements				7,385
Costs capitalized subsequent to acquisition				8,781
Gross amount carried at close of period [Abstract]
Land and improvements				3,797
Buildings and improvements				15,487
Total	$ 19,284			19,284
Accumulated depreciation	$ (9,891)			(9,891)
Date of construction	1992
Date acquired	Jan-97
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 19,284
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 9,891
Encumbered Apartment Communities [Member] | Wilshire Promenade [Member] | Fullerton, CA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	3 years
Encumbered Apartment Communities [Member] | Wilshire Promenade [Member] | Fullerton, CA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Unencumbered Apartment Communities [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	34,441
Initial cost [Abstract]
Land				1,893,634
Buildings and improvements				6,586,618
Costs capitalized subsequent to acquisition				1,153,401
Gross amount carried at close of period [Abstract]
Land and improvements				1,940,335
Buildings and improvements				7,693,318
Total	$ 9,633,653			9,633,653
Accumulated depreciation	(1,887,074)			(1,887,074)
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	9,633,653
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 1,887,074
Unencumbered Apartment Communities [Member] | 1000 Kiely [Member] | Santa Clara, CA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	3 years
Unencumbered Apartment Communities [Member] | 1000 Kiely [Member] | Santa Clara, CA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Unencumbered Apartment Communities [Member] | Eighth And Hope [Member] | Los Angeles, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	290
Initial cost [Abstract]
Land				29,279
Buildings and improvements				169,350
Costs capitalized subsequent to acquisition				2,207
Gross amount carried at close of period [Abstract]
Land and improvements				29,279
Buildings and improvements				171,557
Total	$ 200,836			200,836
Accumulated depreciation	$ (18,558)			(18,558)
Date of construction	2014
Date acquired	Feb-15
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 200,836
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 18,558
Unencumbered Apartment Communities [Member] | Eighth And Hope [Member] | Los Angeles, CA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	3 years
Unencumbered Apartment Communities [Member] | Eighth And Hope [Member] | Los Angeles, CA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Unencumbered Apartment Communities [Member] | Alessio [Member] | Los Angeles, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	624
Initial cost [Abstract]
Land				32,136
Buildings and improvements				128,543
Costs capitalized subsequent to acquisition				7,794
Gross amount carried at close of period [Abstract]
Land and improvements				32,136
Buildings and improvements				136,337
Total	$ 168,473			168,473
Accumulated depreciation	$ (19,336)			(19,336)
Date of construction	2001
Date acquired	Apr-14
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 168,473
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 19,336
Unencumbered Apartment Communities [Member] | Alessio [Member] | Los Angeles, CA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	5 years
Unencumbered Apartment Communities [Member] | Alessio [Member] | Los Angeles, CA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Unencumbered Apartment Communities [Member] | Allegro [Member] | Valley Village, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	97
Initial cost [Abstract]
Land				5,869
Buildings and improvements				23,977
Costs capitalized subsequent to acquisition				1,968
Gross amount carried at close of period [Abstract]
Land and improvements				5,869
Buildings and improvements				25,945
Total	$ 31,814			31,814
Accumulated depreciation	$ (8,463)			(8,463)
Date of construction	2010
Date acquired	Oct-10
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 31,814
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 8,463
Unencumbered Apartment Communities [Member] | Allegro [Member] | Valley Village, CA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	3 years
Unencumbered Apartment Communities [Member] | Allegro [Member] | Valley Village, CA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Unencumbered Apartment Communities [Member] | Allure [Member] | San Diego, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	194
Initial cost [Abstract]
Land				11,923
Buildings and improvements				47,690
Costs capitalized subsequent to acquisition				1,195
Gross amount carried at close of period [Abstract]
Land and improvements				11,923
Buildings and improvements				48,885
Total	$ 60,808			60,808
Accumulated depreciation	$ (6,765)			(6,765)
Date of construction	2002
Date acquired	Apr-14
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 60,808
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 6,765
Unencumbered Apartment Communities [Member] | Allure [Member] | San Diego, CA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	5 years
Unencumbered Apartment Communities [Member] | Allure [Member] | San Diego, CA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Unencumbered Apartment Communities [Member] | Alpine Village [Member] | Alpine, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	301
Initial cost [Abstract]
Land				4,967
Buildings and improvements				19,728
Costs capitalized subsequent to acquisition				8,111
Gross amount carried at close of period [Abstract]
Land and improvements				4,982
Buildings and improvements				27,824
Total	$ 32,806			32,806
Accumulated depreciation	$ (14,106)			(14,106)
Date of construction	1971
Date acquired	Dec-02
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 32,806
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 14,106
Unencumbered Apartment Communities [Member] | Alpine Village [Member] | Alpine, CA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	3 years
Unencumbered Apartment Communities [Member] | Alpine Village [Member] | Alpine, CA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Unencumbered Apartment Communities [Member] | Anavia [Member] | Anaheim, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	250
Initial cost [Abstract]
Land				15,925
Buildings and improvements				63,712
Costs capitalized subsequent to acquisition				7,649
Gross amount carried at close of period [Abstract]
Land and improvements				15,925
Buildings and improvements				71,361
Total	$ 87,286			87,286
Accumulated depreciation	$ (17,162)			(17,162)
Date of construction	2009
Date acquired	Dec-10
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 87,286
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 17,162
Unencumbered Apartment Communities [Member] | Anavia [Member] | Anaheim, CA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	3 years
Unencumbered Apartment Communities [Member] | Anavia [Member] | Anaheim, CA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Unencumbered Apartment Communities [Member] | Annaliese [Member] | Seattle, WA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	56
Initial cost [Abstract]
Land				4,727
Buildings and improvements				14,229
Costs capitalized subsequent to acquisition				525
Gross amount carried at close of period [Abstract]
Land and improvements				4,726
Buildings and improvements				14,755
Total	$ 19,481			19,481
Accumulated depreciation	$ (2,501)			(2,501)
Date of construction	2009
Date acquired	Jan-13
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 19,481
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 2,501
Unencumbered Apartment Communities [Member] | Annaliese [Member] | Seattle, WA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	3 years
Unencumbered Apartment Communities [Member] | Annaliese [Member] | Seattle, WA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Unencumbered Apartment Communities [Member] | Apex [Member] | Milpitas, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	366
Initial cost [Abstract]
Land				44,240
Buildings and improvements				103,251
Costs capitalized subsequent to acquisition				2,512
Gross amount carried at close of period [Abstract]
Land and improvements				44,240
Buildings and improvements				105,763
Total	$ 150,003			150,003
Accumulated depreciation	$ (11,748)			(11,748)
Date of construction	2014
Date acquired	Aug-14
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 150,003
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 11,748
Unencumbered Apartment Communities [Member] | Apex [Member] | Milpitas, CA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	3 years
Unencumbered Apartment Communities [Member] | Apex [Member] | Milpitas, CA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Unencumbered Apartment Communities [Member] | Aqua at Marina Del Rey [Member] | Marina Del Rey, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	500
Initial cost [Abstract]
Land				58,442
Buildings and improvements				175,326
Costs capitalized subsequent to acquisition				11,921
Gross amount carried at close of period [Abstract]
Land and improvements				58,442
Buildings and improvements				187,247
Total	$ 245,689			245,689
Accumulated depreciation	$ (27,261)			(27,261)
Date of construction	2001
Date acquired	Apr-14
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 245,689
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 27,261
Unencumbered Apartment Communities [Member] | Aqua at Marina Del Rey [Member] | Marina Del Rey, CA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	5 years
Unencumbered Apartment Communities [Member] | Aqua at Marina Del Rey [Member] | Marina Del Rey, CA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Unencumbered Apartment Communities [Member] | Ascent [Member] | Kirkland, WA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	90
Initial cost [Abstract]
Land				3,924
Buildings and improvements				11,862
Costs capitalized subsequent to acquisition				1,806
Gross amount carried at close of period [Abstract]
Land and improvements				3,924
Buildings and improvements				13,668
Total	$ 17,592			17,592
Accumulated depreciation	$ (2,937)			(2,937)
Date of construction	1988
Date acquired	Oct-12
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 17,592
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 2,937
Unencumbered Apartment Communities [Member] | Ascent [Member] | Kirkland, WA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	3 years
Unencumbered Apartment Communities [Member] | Ascent [Member] | Kirkland, WA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Unencumbered Apartment Communities [Member] | Ashton Sherman Village [Member] | Los Angeles, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	264
Initial cost [Abstract]
Land				23,550
Buildings and improvements				93,811
Costs capitalized subsequent to acquisition				373
Gross amount carried at close of period [Abstract]
Land and improvements				23,550
Buildings and improvements				94,184
Total	$ 117,734			117,734
Accumulated depreciation	$ (3,442)			(3,442)
Date of construction	2014
Date acquired	Dec-16
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 117,734
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 3,442
Unencumbered Apartment Communities [Member] | Ashton Sherman Village [Member] | Los Angeles, CA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	3 years
Unencumbered Apartment Communities [Member] | Ashton Sherman Village [Member] | Los Angeles, CA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Unencumbered Apartment Communities [Member] | Avant [Member] | Los Angeles, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	440
Initial cost [Abstract]
Land				32,379
Buildings and improvements				137,940
Costs capitalized subsequent to acquisition				1,349
Gross amount carried at close of period [Abstract]
Land and improvements				32,379
Buildings and improvements				139,289
Total	$ 171,668			171,668
Accumulated depreciation	$ (11,397)			(11,397)
Date of construction	2014
Date acquired	Jun-15
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 171,668
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 11,397
Unencumbered Apartment Communities [Member] | Avant [Member] | Los Angeles, CA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	3 years
Unencumbered Apartment Communities [Member] | Avant [Member] | Los Angeles, CA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Unencumbered Apartment Communities [Member] | Avenue 64 [Member] | Emeryville, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	224
Initial cost [Abstract]
Land				27,235
Buildings and improvements				64,403
Costs capitalized subsequent to acquisition				14,013
Gross amount carried at close of period [Abstract]
Land and improvements				27,235
Buildings and improvements				78,416
Total	$ 105,651			105,651
Accumulated depreciation	$ (10,003)			(10,003)
Date of construction	2007
Date acquired	Apr-14
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 105,651
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 10,003
Unencumbered Apartment Communities [Member] | Avenue 64 [Member] | Emeryville, CA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	5 years
Unencumbered Apartment Communities [Member] | Avenue 64 [Member] | Emeryville, CA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Unencumbered Apartment Communities [Member] | Aviara [Member] | Mercer Island, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	166
Initial cost [Abstract]
Land				0
Buildings and improvements				49,813
Costs capitalized subsequent to acquisition				680
Gross amount carried at close of period [Abstract]
Land and improvements				0
Buildings and improvements				50,493
Total	$ 50,493			50,493
Accumulated depreciation	$ (7,820)			(7,820)
Date of construction	2013
Date acquired	Apr-14
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 50,493
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 7,820
Unencumbered Apartment Communities [Member] | Aviara [Member] | Mercer Island, CA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	5 years
Unencumbered Apartment Communities [Member] | Aviara [Member] | Mercer Island, CA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Unencumbered Apartment Communities [Member] | Axis 2300 [Member] | Irvine, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	115
Initial cost [Abstract]
Land				5,405
Buildings and improvements				33,585
Costs capitalized subsequent to acquisition				1,559
Gross amount carried at close of period [Abstract]
Land and improvements				5,405
Buildings and improvements				35,144
Total	$ 40,549			40,549
Accumulated depreciation	$ (11,130)			(11,130)
Date of construction	2010
Date acquired	Aug-10
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 40,549
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 11,130
Unencumbered Apartment Communities [Member] | Axis 2300 [Member] | Irvine, CA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	3 years
Unencumbered Apartment Communities [Member] | Axis 2300 [Member] | Irvine, CA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Unencumbered Apartment Communities [Member] | Bella Villagio [Member] | San Jose, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	231
Initial cost [Abstract]
Land				17,247
Buildings and improvements				40,343
Costs capitalized subsequent to acquisition				3,060
Gross amount carried at close of period [Abstract]
Land and improvements				17,247
Buildings and improvements				43,403
Total	$ 60,650			60,650
Accumulated depreciation	$ (11,390)			(11,390)
Date of construction	2004
Date acquired	Sep-10
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 60,650
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 11,390
Unencumbered Apartment Communities [Member] | Bella Villagio [Member] | San Jose, CA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	3 years
Unencumbered Apartment Communities [Member] | Bella Villagio [Member] | San Jose, CA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Unencumbered Apartment Communities [Member] | Bellerive [Member] | Los Angeles, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	63
Initial cost [Abstract]
Land				5,401
Buildings and improvements				21,803
Costs capitalized subsequent to acquisition				1,104
Gross amount carried at close of period [Abstract]
Land and improvements				5,401
Buildings and improvements				22,907
Total	$ 28,308			28,308
Accumulated depreciation	$ (6,181)			(6,181)
Date of construction	2011
Date acquired	Aug-11
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 28,308
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 6,181
Unencumbered Apartment Communities [Member] | Bellerive [Member] | Los Angeles, CA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	3 years
Unencumbered Apartment Communities [Member] | Bellerive [Member] | Los Angeles, CA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Unencumbered Apartment Communities [Member] | Belmont Terrace [Member] | Belmont, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	71
Initial cost [Abstract]
Land				4,446
Buildings and improvements				10,290
Costs capitalized subsequent to acquisition				6,203
Gross amount carried at close of period [Abstract]
Land and improvements				4,473
Buildings and improvements				16,466
Total	$ 20,939			20,939
Accumulated depreciation	$ (7,161)			(7,161)
Date of construction	1974
Date acquired	Oct-06
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 20,939
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 7,161
Unencumbered Apartment Communities [Member] | Belmont Terrace [Member] | Belmont, CA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	3 years
Unencumbered Apartment Communities [Member] | Belmont Terrace [Member] | Belmont, CA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Unencumbered Apartment Communities [Member] | Bennett Lofts [Member] | San Francisco, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	165
Initial cost [Abstract]
Land				21,771
Buildings and improvements				50,800
Costs capitalized subsequent to acquisition				28,948
Gross amount carried at close of period [Abstract]
Land and improvements				28,371
Buildings and improvements				73,148
Total	$ 101,519			101,519
Accumulated depreciation	$ (13,218)			(13,218)
Date of construction	2004
Date acquired	Dec-12
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 101,519
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 13,218
Unencumbered Apartment Communities [Member] | Bennett Lofts [Member] | San Francisco, CA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	3 years
Unencumbered Apartment Communities [Member] | Bennett Lofts [Member] | San Francisco, CA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Unencumbered Apartment Communities [Member] | Bernardo Crest [Member] | San Diego, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	216
Initial cost [Abstract]
Land				10,802
Buildings and improvements				43,209
Costs capitalized subsequent to acquisition				2,738
Gross amount carried at close of period [Abstract]
Land and improvements				10,802
Buildings and improvements				45,947
Total	$ 56,749			56,749
Accumulated depreciation	$ (6,542)			(6,542)
Date of construction	1988
Date acquired	Apr-14
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 56,749
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 6,542
Unencumbered Apartment Communities [Member] | Bernardo Crest [Member] | San Diego, CA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	5 years
Unencumbered Apartment Communities [Member] | Bernardo Crest [Member] | San Diego, CA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Unencumbered Apartment Communities [Member] | Bonita Cedars [Member] | Bonita, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	120
Initial cost [Abstract]
Land				2,496
Buildings and improvements				9,913
Costs capitalized subsequent to acquisition				3,985
Gross amount carried at close of period [Abstract]
Land and improvements				2,503
Buildings and improvements				13,891
Total	$ 16,394			16,394
Accumulated depreciation	$ (6,742)			(6,742)
Date of construction	1983
Date acquired	Dec-02
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 16,394
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 6,742
Unencumbered Apartment Communities [Member] | Bonita Cedars [Member] | Bonita, CA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	3 years
Unencumbered Apartment Communities [Member] | Bonita Cedars [Member] | Bonita, CA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Unencumbered Apartment Communities [Member] | Boulevard [Member] | Fremont, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	172
Initial cost [Abstract]
Land				3,520
Buildings and improvements				8,182
Costs capitalized subsequent to acquisition				12,963
Gross amount carried at close of period [Abstract]
Land and improvements				3,580
Buildings and improvements				21,085
Total	$ 24,665			24,665
Accumulated depreciation	$ (16,059)			(16,059)
Date of construction	1978
Date acquired	Jan-96
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 24,665
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 16,059
Unencumbered Apartment Communities [Member] | Boulevard [Member] | Fremont, CA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	3 years
Unencumbered Apartment Communities [Member] | Boulevard [Member] | Fremont, CA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Unencumbered Apartment Communities [Member] | Bridle Trails [Member] | Kirkland, WA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	108
Initial cost [Abstract]
Land				1,500
Buildings and improvements				5,930
Costs capitalized subsequent to acquisition				5,812
Gross amount carried at close of period [Abstract]
Land and improvements				1,531
Buildings and improvements				11,711
Total	$ 13,242			13,242
Accumulated depreciation	$ (8,081)			(8,081)
Date of construction	1986
Date acquired	Oct-97
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 13,242
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 8,081
Unencumbered Apartment Communities [Member] | Bridle Trails [Member] | Kirkland, WA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	3 years
Unencumbered Apartment Communities [Member] | Bridle Trails [Member] | Kirkland, WA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Unencumbered Apartment Communities [Member] | Brighton Ridge [Member] | Renton, WA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	264
Initial cost [Abstract]
Land				2,623
Buildings and improvements				10,800
Costs capitalized subsequent to acquisition				4,966
Gross amount carried at close of period [Abstract]
Land and improvements				2,656
Buildings and improvements				15,733
Total	$ 18,389			18,389
Accumulated depreciation	$ (11,110)			(11,110)
Date of construction	1986
Date acquired	Dec-96
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 18,389
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 11,110
Unencumbered Apartment Communities [Member] | Brighton Ridge [Member] | Renton, WA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	3 years
Unencumbered Apartment Communities [Member] | Brighton Ridge [Member] | Renton, WA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Unencumbered Apartment Communities [Member] | Bristol Commons [Member] | Sunnyvale, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	188
Initial cost [Abstract]
Land				5,278
Buildings and improvements				11,853
Costs capitalized subsequent to acquisition				8,861
Gross amount carried at close of period [Abstract]
Land and improvements				5,293
Buildings and improvements				20,699
Total	$ 25,992			25,992
Accumulated depreciation	$ (12,709)			(12,709)
Date of construction	1989
Date acquired	Jan-95
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 25,992
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 12,709
Unencumbered Apartment Communities [Member] | Bristol Commons [Member] | Sunnyvale, CA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	3 years
Unencumbered Apartment Communities [Member] | Bristol Commons [Member] | Sunnyvale, CA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Unencumbered Apartment Communities [Member] | 416 on Broadway [Member] | Glendale, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	115
Initial cost [Abstract]
Land				8,557
Buildings and improvements				34,235
Costs capitalized subsequent to acquisition				2,296
Gross amount carried at close of period [Abstract]
Land and improvements				8,557
Buildings and improvements				36,531
Total	$ 45,088			45,088
Accumulated depreciation	$ (9,509)			(9,509)
Date of construction	2009
Date acquired	Dec-10
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 45,088
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 9,509
Unencumbered Apartment Communities [Member] | 416 on Broadway [Member] | Glendale, CA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	3 years
Unencumbered Apartment Communities [Member] | 416 on Broadway [Member] | Glendale, CA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Unencumbered Apartment Communities [Member] | Bunker Hill [Member] | Los Angeles, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	456
Initial cost [Abstract]
Land				11,498
Buildings and improvements				27,871
Costs capitalized subsequent to acquisition				75,593
Gross amount carried at close of period [Abstract]
Land and improvements				11,639
Buildings and improvements				103,323
Total	$ 114,962			114,962
Accumulated depreciation	$ (43,100)			(43,100)
Date of construction	1968
Date acquired	Mar-98
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 114,962
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 43,100
Unencumbered Apartment Communities [Member] | Bunker Hill [Member] | Los Angeles, CA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	3 years
Unencumbered Apartment Communities [Member] | Bunker Hill [Member] | Los Angeles, CA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Unencumbered Apartment Communities [Member] | Camarillo Oaks [Member] | Camarillo, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	564
Initial cost [Abstract]
Land				10,953
Buildings and improvements				25,254
Costs capitalized subsequent to acquisition				6,100
Gross amount carried at close of period [Abstract]
Land and improvements				11,075
Buildings and improvements				31,232
Total	$ 42,307			42,307
Accumulated depreciation	$ (21,946)			(21,946)
Date of construction	1985
Date acquired	Jul-96
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 42,307
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 21,946
Unencumbered Apartment Communities [Member] | Camarillo Oaks [Member] | Camarillo, CA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	3 years
Unencumbered Apartment Communities [Member] | Camarillo Oaks [Member] | Camarillo, CA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Unencumbered Apartment Communities [Member] | Cambridge Park [Member] | San Diego, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	320
Initial cost [Abstract]
Land				18,185
Buildings and improvements				72,739
Costs capitalized subsequent to acquisition				2,492
Gross amount carried at close of period [Abstract]
Land and improvements				18,185
Buildings and improvements				75,231
Total	$ 93,416			93,416
Accumulated depreciation	$ (10,691)			(10,691)
Date of construction	1998
Date acquired	Apr-14
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 93,416
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 10,691
Unencumbered Apartment Communities [Member] | Cambridge Park [Member] | San Diego, CA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	5 years
Unencumbered Apartment Communities [Member] | Cambridge Park [Member] | San Diego, CA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Unencumbered Apartment Communities [Member] | Camino Ruiz Square [Member] | Camarillo, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	159
Initial cost [Abstract]
Land				6,871
Buildings and improvements				26,119
Costs capitalized subsequent to acquisition				1,886
Gross amount carried at close of period [Abstract]
Land and improvements				6,931
Buildings and improvements				27,945
Total	$ 34,876			34,876
Accumulated depreciation	$ (10,569)			(10,569)
Date of construction	1990
Date acquired	Dec-06
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 34,876
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 10,569
Unencumbered Apartment Communities [Member] | Camino Ruiz Square [Member] | Camarillo, CA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	3 years
Unencumbered Apartment Communities [Member] | Camino Ruiz Square [Member] | Camarillo, CA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Unencumbered Apartment Communities [Member] | Canyon Oaks [Member] | San Ramon, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	250
Initial cost [Abstract]
Land				19,088
Buildings and improvements				44,473
Costs capitalized subsequent to acquisition				3,404
Gross amount carried at close of period [Abstract]
Land and improvements				19,088
Buildings and improvements				47,877
Total	$ 66,965			66,965
Accumulated depreciation	$ (17,672)			(17,672)
Date of construction	2005
Date acquired	May-07
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 66,965
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 17,672
Unencumbered Apartment Communities [Member] | Canyon Oaks [Member] | San Ramon, CA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	3 years
Unencumbered Apartment Communities [Member] | Canyon Oaks [Member] | San Ramon, CA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Unencumbered Apartment Communities [Member] | Canyon Pointe [Member] | Bothell, WA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	250
Initial cost [Abstract]
Land				4,692
Buildings and improvements				18,288
Costs capitalized subsequent to acquisition				7,017
Gross amount carried at close of period [Abstract]
Land and improvements				4,693
Buildings and improvements				25,304
Total	$ 29,997			29,997
Accumulated depreciation	$ (13,092)			(13,092)
Date of construction	1990
Date acquired	Oct-03
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 29,997
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 13,092
Unencumbered Apartment Communities [Member] | Canyon Pointe [Member] | Bothell, WA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	3 years
Unencumbered Apartment Communities [Member] | Canyon Pointe [Member] | Bothell, WA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Unencumbered Apartment Communities [Member] | Capri at Sunny Hills [Member] | Fullerton, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	102
Initial cost [Abstract]
Land				3,337
Buildings and improvements				13,320
Costs capitalized subsequent to acquisition				9,040
Gross amount carried at close of period [Abstract]
Land and improvements				4,048
Buildings and improvements				21,649
Total	$ 25,697			25,697
Accumulated depreciation	$ (12,460)			(12,460)
Date of construction	1961
Date acquired	Sep-01
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 25,697
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 12,460
Unencumbered Apartment Communities [Member] | Capri at Sunny Hills [Member] | Fullerton, CA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	3 years
Unencumbered Apartment Communities [Member] | Capri at Sunny Hills [Member] | Fullerton, CA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Unencumbered Apartment Communities [Member] | Carnel Landing [Member] | San Diego, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	356
Initial cost [Abstract]
Land				16,725
Buildings and improvements				66,901
Costs capitalized subsequent to acquisition				6,128
Gross amount carried at close of period [Abstract]
Land and improvements				16,725
Buildings and improvements				73,029
Total	$ 89,754			89,754
Accumulated depreciation	$ (10,364)			(10,364)
Date of construction	1989
Date acquired	Apr-14
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 89,754
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 10,364
Unencumbered Apartment Communities [Member] | Carnel Landing [Member] | San Diego, CA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	5 years
Unencumbered Apartment Communities [Member] | Carnel Landing [Member] | San Diego, CA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Unencumbered Apartment Communities [Member] | Carnel Summit [Member] | San Diego, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	246
Initial cost [Abstract]
Land				14,968
Buildings and improvements				59,871
Costs capitalized subsequent to acquisition				2,886
Gross amount carried at close of period [Abstract]
Land and improvements				14,968
Buildings and improvements				62,757
Total	$ 77,725			77,725
Accumulated depreciation	$ (8,747)			(8,747)
Date of construction	1989
Date acquired	Apr-14
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 77,725
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 8,747
Unencumbered Apartment Communities [Member] | Carnel Summit [Member] | San Diego, CA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	5 years
Unencumbered Apartment Communities [Member] | Carnel Summit [Member] | San Diego, CA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Unencumbered Apartment Communities [Member] | Castle Creek [Member] | New Castle, WA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	216
Initial cost [Abstract]
Land				4,149
Buildings and improvements				16,028
Costs capitalized subsequent to acquisition				3,760
Gross amount carried at close of period [Abstract]
Land and improvements				4,833
Buildings and improvements				19,104
Total	$ 23,937			23,937
Accumulated depreciation	$ (13,088)			(13,088)
Date of construction	1998
Date acquired	Dec-98
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 23,937
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 13,088
Unencumbered Apartment Communities [Member] | Castle Creek [Member] | New Castle, WA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	3 years
Unencumbered Apartment Communities [Member] | Castle Creek [Member] | New Castle, WA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Unencumbered Apartment Communities [Member] | Catalina Gardens [Member] | Los Angeles, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	128
Initial cost [Abstract]
Land				6,714
Buildings and improvements				26,856
Costs capitalized subsequent to acquisition				1,043
Gross amount carried at close of period [Abstract]
Land and improvements				6,714
Buildings and improvements				27,899
Total	$ 34,613			34,613
Accumulated depreciation	$ (3,890)			(3,890)
Date of construction	1987
Date acquired	Apr-14
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 34,613
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 3,890
Unencumbered Apartment Communities [Member] | Catalina Gardens [Member] | Los Angeles, CA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	5 years
Unencumbered Apartment Communities [Member] | Catalina Gardens [Member] | Los Angeles, CA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Unencumbered Apartment Communities [Member] | CBC Apartments [Member] | Goleta, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	239
Initial cost [Abstract]
Land				11,841
Buildings and improvements				45,320
Costs capitalized subsequent to acquisition				6,162
Gross amount carried at close of period [Abstract]
Land and improvements				11,906
Buildings and improvements				51,417
Total	$ 63,323			63,323
Accumulated depreciation	$ (22,887)			(22,887)
Date of construction	1962
Date acquired	Jan-06
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 63,323
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 22,887
Unencumbered Apartment Communities [Member] | CBC Apartments [Member] | Goleta, CA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	3 years
Unencumbered Apartment Communities [Member] | CBC Apartments [Member] | Goleta, CA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Unencumbered Apartment Communities [Member] | Cedar Terrace [Member] | Bellevue, WA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	180
Initial cost [Abstract]
Land				5,543
Buildings and improvements				16,442
Costs capitalized subsequent to acquisition				5,923
Gross amount carried at close of period [Abstract]
Land and improvements				5,652
Buildings and improvements				22,256
Total	$ 27,908			27,908
Accumulated depreciation	$ (10,561)			(10,561)
Date of construction	1984
Date acquired	Jan-05
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 27,908
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 10,561
Unencumbered Apartment Communities [Member] | Cedar Terrace [Member] | Bellevue, WA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	3 years
Unencumbered Apartment Communities [Member] | Cedar Terrace [Member] | Bellevue, WA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Unencumbered Apartment Communities [Member] | CentrePointe [Member] | San Diego, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	224
Initial cost [Abstract]
Land				3,405
Buildings and improvements				7,743
Costs capitalized subsequent to acquisition				21,252
Gross amount carried at close of period [Abstract]
Land and improvements				3,442
Buildings and improvements				28,958
Total	$ 32,400			32,400
Accumulated depreciation	$ (16,021)			(16,021)
Date of construction	1974
Date acquired	Jun-97
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 32,400
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 16,021
Unencumbered Apartment Communities [Member] | CentrePointe [Member] | San Diego, CA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	3 years
Unencumbered Apartment Communities [Member] | CentrePointe [Member] | San Diego, CA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Unencumbered Apartment Communities [Member] | Chestnut Street [Member] | Santa Cruz, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	96
Initial cost [Abstract]
Land				6,582
Buildings and improvements				15,689
Costs capitalized subsequent to acquisition				1,750
Gross amount carried at close of period [Abstract]
Land and improvements				6,582
Buildings and improvements				17,439
Total	$ 24,021			24,021
Accumulated depreciation	$ (5,821)			(5,821)
Date of construction	2002
Date acquired	Jul-08
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 24,021
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 5,821
Unencumbered Apartment Communities [Member] | Chestnut Street [Member] | Santa Cruz, CA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	3 years
Unencumbered Apartment Communities [Member] | Chestnut Street [Member] | Santa Cruz, CA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Unencumbered Apartment Communities [Member] | Collins On Pine [Member] | Seattle, WA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	76
Initial cost [Abstract]
Land				7,276
Buildings and improvements				22,226
Costs capitalized subsequent to acquisition				262
Gross amount carried at close of period [Abstract]
Land and improvements				7,276
Buildings and improvements				22,488
Total	$ 29,764			29,764
Accumulated depreciation	$ (2,737)			(2,737)
Date of construction	2013
Date acquired	May-14
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 29,764
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 2,737
Unencumbered Apartment Communities [Member] | Collins On Pine [Member] | Seattle, WA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	3 years
Unencumbered Apartment Communities [Member] | Collins On Pine [Member] | Seattle, WA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Unencumbered Apartment Communities [Member] | Corbella at Juanita Bay [Member] | Kirkland, WA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	169
Initial cost [Abstract]
Land				5,801
Buildings and improvements				17,415
Costs capitalized subsequent to acquisition				2,603
Gross amount carried at close of period [Abstract]
Land and improvements				5,801
Buildings and improvements				20,018
Total	$ 25,819			25,819
Accumulated depreciation	$ (5,368)			(5,368)
Date of construction	1978
Date acquired	Nov-10
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 25,819
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 5,368
Unencumbered Apartment Communities [Member] | Corbella at Juanita Bay [Member] | Kirkland, WA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	3 years
Unencumbered Apartment Communities [Member] | Corbella at Juanita Bay [Member] | Kirkland, WA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Unencumbered Apartment Communities [Member] | Cortesia [Member] | Rancho Santa Margarita, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	308
Initial cost [Abstract]
Land				13,912
Buildings and improvements				55,649
Costs capitalized subsequent to acquisition				1,958
Gross amount carried at close of period [Abstract]
Land and improvements				13,912
Buildings and improvements				57,607
Total	$ 71,519			71,519
Accumulated depreciation	$ (8,058)			(8,058)
Date of construction	1999
Date acquired	Apr-14
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 71,519
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 8,058
Unencumbered Apartment Communities [Member] | Cortesia [Member] | Rancho Santa Margarita, CA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	5 years
Unencumbered Apartment Communities [Member] | Cortesia [Member] | Rancho Santa Margarita, CA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Unencumbered Apartment Communities [Member] | Country Villas [Member] | Oceanside, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	180
Initial cost [Abstract]
Land				4,174
Buildings and improvements				16,583
Costs capitalized subsequent to acquisition				4,772
Gross amount carried at close of period [Abstract]
Land and improvements				4,187
Buildings and improvements				21,342
Total	$ 25,529			25,529
Accumulated depreciation	$ (11,005)			(11,005)
Date of construction	1976
Date acquired	Dec-02
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 25,529
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 11,005
Unencumbered Apartment Communities [Member] | Country Villas [Member] | Oceanside, CA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	3 years
Unencumbered Apartment Communities [Member] | Country Villas [Member] | Oceanside, CA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Unencumbered Apartment Communities [Member] | Crow Canyon [Member] | San Ramon, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	400
Initial cost [Abstract]
Land				37,579
Buildings and improvements				87,685
Costs capitalized subsequent to acquisition				7,616
Gross amount carried at close of period [Abstract]
Land and improvements				37,579
Buildings and improvements				95,301
Total	$ 132,880			132,880
Accumulated depreciation	$ (13,111)			(13,111)
Date of construction	1992
Date acquired	Apr-14
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 132,880
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 13,111
Unencumbered Apartment Communities [Member] | Crow Canyon [Member] | San Ramon, CA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	5 years
Unencumbered Apartment Communities [Member] | Crow Canyon [Member] | San Ramon, CA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Unencumbered Apartment Communities [Member] | Deer Valley [Member] | San Rafael, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	171
Initial cost [Abstract]
Land				21,478
Buildings and improvements				50,116
Costs capitalized subsequent to acquisition				2,113
Gross amount carried at close of period [Abstract]
Land and improvements				21,478
Buildings and improvements				52,229
Total	$ 73,707			73,707
Accumulated depreciation	$ (7,425)			(7,425)
Date of construction	1996
Date acquired	Apr-14
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 73,707
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 7,425
Unencumbered Apartment Communities [Member] | Deer Valley [Member] | San Rafael, CA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	5 years
Unencumbered Apartment Communities [Member] | Deer Valley [Member] | San Rafael, CA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Unencumbered Apartment Communities [Member] | Delano [Member] | Redmond, WA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	126
Initial cost [Abstract]
Land				7,470
Buildings and improvements				22,511
Costs capitalized subsequent to acquisition				1,167
Gross amount carried at close of period [Abstract]
Land and improvements				7,470
Buildings and improvements				23,678
Total	$ 31,148			31,148
Accumulated depreciation	$ (4,984)			(4,984)
Date of construction	2005
Date acquired	Dec-11
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 31,148
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 4,984
Unencumbered Apartment Communities [Member] | Delano [Member] | Redmond, WA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	3 years
Unencumbered Apartment Communities [Member] | Delano [Member] | Redmond, WA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Unencumbered Apartment Communities [Member] | Devonshire [Member] | Hemet, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	276
Initial cost [Abstract]
Land				3,470
Buildings and improvements				13,786
Costs capitalized subsequent to acquisition				3,935
Gross amount carried at close of period [Abstract]
Land and improvements				3,482
Buildings and improvements				17,709
Total	$ 21,191			21,191
Accumulated depreciation	$ (9,455)			(9,455)
Date of construction	1988
Date acquired	Dec-02
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 21,191
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 9,455
Unencumbered Apartment Communities [Member] | Devonshire [Member] | Hemet, CA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	3 years
Unencumbered Apartment Communities [Member] | Devonshire [Member] | Hemet, CA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Unencumbered Apartment Communities [Member] | Domain [Member] | San Diego, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	379
Initial cost [Abstract]
Land				23,848
Buildings and improvements				95,394
Costs capitalized subsequent to acquisition				1,298
Gross amount carried at close of period [Abstract]
Land and improvements				23,848
Buildings and improvements				96,692
Total	$ 120,540			120,540
Accumulated depreciation	$ (13,510)			(13,510)
Date of construction	2013
Date acquired	Nov-13
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 120,540
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 13,510
Unencumbered Apartment Communities [Member] | Domain [Member] | San Diego, CA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	3 years
Unencumbered Apartment Communities [Member] | Domain [Member] | San Diego, CA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Unencumbered Apartment Communities [Member] | Emerald Pointe [Member] | Diamond Bar, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	160
Initial cost [Abstract]
Land				8,458
Buildings and improvements				33,832
Costs capitalized subsequent to acquisition				1,468
Gross amount carried at close of period [Abstract]
Land and improvements				8,458
Buildings and improvements				35,300
Total	$ 43,758			43,758
Accumulated depreciation	$ (5,018)			(5,018)
Date of construction	1989
Date acquired	Apr-14
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 43,758
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 5,018
Unencumbered Apartment Communities [Member] | Emerald Pointe [Member] | Diamond Bar, CA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	5 years
Unencumbered Apartment Communities [Member] | Emerald Pointe [Member] | Diamond Bar, CA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Unencumbered Apartment Communities [Member] | Emerald Ridge [Member] | Bellevue, WA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	180
Initial cost [Abstract]
Land				3,449
Buildings and improvements				7,801
Costs capitalized subsequent to acquisition				5,199
Gross amount carried at close of period [Abstract]
Land and improvements				3,449
Buildings and improvements				13,000
Total	$ 16,449			16,449
Accumulated depreciation	$ (9,551)			(9,551)
Date of construction	1987
Date acquired	Nov-94
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 16,449
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 9,551
Unencumbered Apartment Communities [Member] | Emerald Ridge [Member] | Bellevue, WA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	3 years
Unencumbered Apartment Communities [Member] | Emerald Ridge [Member] | Bellevue, WA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Unencumbered Apartment Communities [Member] | Emerson Valley Village [Member] | Los Angeles, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	144
Initial cost [Abstract]
Land				13,378
Buildings and improvements				53,240
Costs capitalized subsequent to acquisition				284
Gross amount carried at close of period [Abstract]
Land and improvements				13,378
Buildings and improvements				53,524
Total	$ 66,902			66,902
Accumulated depreciation	$ (1,953)			(1,953)
Date of construction	2012
Date acquired	Dec-16
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 66,902
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 1,953
Unencumbered Apartment Communities [Member] | Emerson Valley Village [Member] | Los Angeles, CA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	3 years
Unencumbered Apartment Communities [Member] | Emerson Valley Village [Member] | Los Angeles, CA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Unencumbered Apartment Communities [Member] | Enso [Member] | San Jose, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	183
Initial cost [Abstract]
Land				21,397
Buildings and improvements				71,135
Costs capitalized subsequent to acquisition				1,153
Gross amount carried at close of period [Abstract]
Land and improvements				21,397
Buildings and improvements				72,288
Total	$ 93,685			93,685
Accumulated depreciation	$ (5,238)			(5,238)
Date of construction	2014
Date acquired	Dec-15
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 93,685
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 5,238
Unencumbered Apartment Communities [Member] | Enso [Member] | San Jose, CA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	3 years
Unencumbered Apartment Communities [Member] | Enso [Member] | San Jose, CA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Unencumbered Apartment Communities [Member] | Esplanade [Member] | San Jose, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	278
Initial cost [Abstract]
Land				18,170
Buildings and improvements				40,086
Costs capitalized subsequent to acquisition				11,945
Gross amount carried at close of period [Abstract]
Land and improvements				18,429
Buildings and improvements				51,772
Total	$ 70,201			70,201
Accumulated depreciation	$ (24,281)			(24,281)
Date of construction	2002
Date acquired	Apr-04
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 70,201
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 24,281
Unencumbered Apartment Communities [Member] | Esplanade [Member] | San Jose, CA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	3 years
Unencumbered Apartment Communities [Member] | Esplanade [Member] | San Jose, CA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Unencumbered Apartment Communities [Member] | Essex Skyline [Member] | Santa Ana, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	349
Initial cost [Abstract]
Land				21,537
Buildings and improvements				146,099
Costs capitalized subsequent to acquisition				6,340
Gross amount carried at close of period [Abstract]
Land and improvements				21,537
Buildings and improvements				152,439
Total	$ 173,976			173,976
Accumulated depreciation	$ (29,843)			(29,843)
Date of construction	2008
Date acquired	Apr-10
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 173,976
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 29,843
Unencumbered Apartment Communities [Member] | Essex Skyline [Member] | Santa Ana, CA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	3 years
Unencumbered Apartment Communities [Member] | Essex Skyline [Member] | Santa Ana, CA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Unencumbered Apartment Communities [Member] | Evergreen Heights [Member] | Kirkland, WA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	200
Initial cost [Abstract]
Land				3,566
Buildings and improvements				13,395
Costs capitalized subsequent to acquisition				5,345
Gross amount carried at close of period [Abstract]
Land and improvements				3,649
Buildings and improvements				18,657
Total	$ 22,306			22,306
Accumulated depreciation	$ (12,816)			(12,816)
Date of construction	1990
Date acquired	Jun-97
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 22,306
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 12,816
Unencumbered Apartment Communities [Member] | Evergreen Heights [Member] | Kirkland, WA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	3 years
Unencumbered Apartment Communities [Member] | Evergreen Heights [Member] | Kirkland, WA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Unencumbered Apartment Communities [Member] | Fairway Apartments at Big Canyon [Member] | Newport Beach, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	74
Initial cost [Abstract]
Land				0
Buildings and improvements				7,850
Costs capitalized subsequent to acquisition				7,583
Gross amount carried at close of period [Abstract]
Land and improvements				0
Buildings and improvements				15,433
Total	$ 15,433			15,433
Accumulated depreciation	$ (9,692)			(9,692)
Date of construction	1972
Date acquired	Jun-99
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 15,433
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 9,692
Unencumbered Apartment Communities [Member] | Fairway Apartments at Big Canyon [Member] | Newport Beach, CA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	3 years
Unencumbered Apartment Communities [Member] | Fairway Apartments at Big Canyon [Member] | Newport Beach, CA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	28 years
Unencumbered Apartment Communities [Member] | Fairwood Pond [Member] | Renton, WA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	194
Initial cost [Abstract]
Land				5,296
Buildings and improvements				15,564
Costs capitalized subsequent to acquisition				3,122
Gross amount carried at close of period [Abstract]
Land and improvements				5,297
Buildings and improvements				18,685
Total	$ 23,982			23,982
Accumulated depreciation	$ (8,928)			(8,928)
Date of construction	1997
Date acquired	Oct-04
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 23,982
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 8,928
Unencumbered Apartment Communities [Member] | Fairwood Pond [Member] | Renton, WA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	3 years
Unencumbered Apartment Communities [Member] | Fairwood Pond [Member] | Renton, WA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Unencumbered Apartment Communities [Member] | Foothill Commons [Member] | Bellevue, WA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	394
Initial cost [Abstract]
Land				2,435
Buildings and improvements				9,821
Costs capitalized subsequent to acquisition				39,142
Gross amount carried at close of period [Abstract]
Land and improvements				2,440
Buildings and improvements				48,958
Total	$ 51,398			51,398
Accumulated depreciation	$ (38,723)			(38,723)
Date of construction	1978
Date acquired	Mar-90
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 51,398
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 38,723
Unencumbered Apartment Communities [Member] | Foothill Commons [Member] | Bellevue, WA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	3 years
Unencumbered Apartment Communities [Member] | Foothill Commons [Member] | Bellevue, WA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Unencumbered Apartment Communities [Member] | Foothill Gardens/Twin Creeks [Member] | San Ramon, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	176
Initial cost [Abstract]
Land				5,875
Buildings and improvements				13,992
Costs capitalized subsequent to acquisition				10,086
Gross amount carried at close of period [Abstract]
Land and improvements				5,964
Buildings and improvements				23,989
Total	$ 29,953			29,953
Accumulated depreciation	$ (15,203)			(15,203)
Date of construction	1985
Date acquired	Feb-97
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 29,953
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 15,203
Unencumbered Apartment Communities [Member] | Foothill Gardens/Twin Creeks [Member] | San Ramon, CA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	3 years
Unencumbered Apartment Communities [Member] | Foothill Gardens/Twin Creeks [Member] | San Ramon, CA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Unencumbered Apartment Communities [Member] | Forest View [Member] | Renton, WA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	192
Initial cost [Abstract]
Land				3,731
Buildings and improvements				14,530
Costs capitalized subsequent to acquisition				2,362
Gross amount carried at close of period [Abstract]
Land and improvements				3,731
Buildings and improvements				16,892
Total	$ 20,623			20,623
Accumulated depreciation	$ (8,351)			(8,351)
Date of construction	1998
Date acquired	Oct-03
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 20,623
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 8,351
Unencumbered Apartment Communities [Member] | Forest View [Member] | Renton, WA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	3 years
Unencumbered Apartment Communities [Member] | Forest View [Member] | Renton, WA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Unencumbered Apartment Communities [Member] | Fountain Court [Member] | Seattle, WA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	320
Initial cost [Abstract]
Land				6,702
Buildings and improvements				27,306
Costs capitalized subsequent to acquisition				11,409
Gross amount carried at close of period [Abstract]
Land and improvements				6,585
Buildings and improvements				38,832
Total	$ 45,417			45,417
Accumulated depreciation	$ (23,649)			(23,649)
Date of construction	2000
Date acquired	Mar-00
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 45,417
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 23,649
Unencumbered Apartment Communities [Member] | Fountain Court [Member] | Seattle, WA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	3 years
Unencumbered Apartment Communities [Member] | Fountain Court [Member] | Seattle, WA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Unencumbered Apartment Communities [Member] | Fourth & U [Member] | Berkeley, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	171
Initial cost [Abstract]
Land				8,879
Buildings and improvements				52,351
Costs capitalized subsequent to acquisition				2,775
Gross amount carried at close of period [Abstract]
Land and improvements				8,879
Buildings and improvements				55,126
Total	$ 64,005			64,005
Accumulated depreciation	$ (15,677)			(15,677)
Date of construction	2010
Date acquired	Apr-10
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 64,005
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 15,677
Unencumbered Apartment Communities [Member] | Fourth & U [Member] | Berkeley, CA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	3 years
Unencumbered Apartment Communities [Member] | Fourth & U [Member] | Berkeley, CA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Unencumbered Apartment Communities [Member] | Fox Plaza [Member] | San Francisco, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	444
Initial cost [Abstract]
Land				39,731
Buildings and improvements				92,706
Costs capitalized subsequent to acquisition				20,638
Gross amount carried at close of period [Abstract]
Land and improvements				39,731
Buildings and improvements				113,344
Total	$ 153,075			153,075
Accumulated depreciation	$ (21,219)			(21,219)
Date of construction	1968
Date acquired	Feb-13
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 153,075
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 21,219
Unencumbered Apartment Communities [Member] | Fox Plaza [Member] | San Francisco, CA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	3 years
Unencumbered Apartment Communities [Member] | Fox Plaza [Member] | San Francisco, CA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Unencumbered Apartment Communities [Member] | Hampton Place Hampton Court [Member] | Glendale, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	215
Initial cost [Abstract]
Land				6,695
Buildings and improvements				16,753
Costs capitalized subsequent to acquisition				24,885
Gross amount carried at close of period [Abstract]
Land and improvements				6,733
Buildings and improvements				41,600
Total	$ 48,333			48,333
Accumulated depreciation	$ (18,798)			(18,798)
Date of construction	1970
Date acquired	Jun-99
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 48,333
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 18,798
Unencumbered Apartment Communities [Member] | Hampton Place Hampton Court [Member] | Glendale, CA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	3 years
Unencumbered Apartment Communities [Member] | Hampton Place Hampton Court [Member] | Glendale, CA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Unencumbered Apartment Communities [Member] | Hillsdale Garden Apartments [Member] | San Mateo, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	697
Initial cost [Abstract]
Land				22,000
Buildings and improvements				94,681
Costs capitalized subsequent to acquisition				22,145
Gross amount carried at close of period [Abstract]
Land and improvements				22,000
Buildings and improvements				116,826
Total	$ 138,826			138,826
Accumulated depreciation	$ (49,216)			(49,216)
Date of construction	1948
Date acquired	Sep-06
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 138,826
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 49,216
Unencumbered Apartment Communities [Member] | Hillsdale Garden Apartments [Member] | San Mateo, CA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	3 years
Unencumbered Apartment Communities [Member] | Hillsdale Garden Apartments [Member] | San Mateo, CA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Unencumbered Apartment Communities [Member] | Hope Ranch Collection [Member] | Santa Barbara, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	108
Initial cost [Abstract]
Land				4,078
Buildings and improvements				16,877
Costs capitalized subsequent to acquisition				2,825
Gross amount carried at close of period [Abstract]
Land and improvements				4,208
Buildings and improvements				19,572
Total	$ 23,780			23,780
Accumulated depreciation	$ (7,105)			(7,105)
Date of construction	1965
Date acquired	Mar-07
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 23,780
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 7,105
Unencumbered Apartment Communities [Member] | Hope Ranch Collection [Member] | Santa Barbara, CA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	3 years
Unencumbered Apartment Communities [Member] | Hope Ranch Collection [Member] | Santa Barbara, CA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Unencumbered Apartment Communities [Member] | Joule [Member] | Seattle, WA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	295
Initial cost [Abstract]
Land				14,558
Buildings and improvements				69,417
Costs capitalized subsequent to acquisition				4,295
Gross amount carried at close of period [Abstract]
Land and improvements				14,558
Buildings and improvements				73,712
Total	$ 88,270			88,270
Accumulated depreciation	$ (21,397)			(21,397)
Date of construction	2010
Date acquired	Mar-10
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 88,270
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 21,397
Unencumbered Apartment Communities [Member] | Joule [Member] | Seattle, WA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	3 years
Unencumbered Apartment Communities [Member] | Joule [Member] | Seattle, WA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Unencumbered Apartment Communities [Member] | Kings Road [Member] | Los Angeles, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	196
Initial cost [Abstract]
Land				4,023
Buildings and improvements				9,527
Costs capitalized subsequent to acquisition				14,593
Gross amount carried at close of period [Abstract]
Land and improvements				4,031
Buildings and improvements				24,112
Total	$ 28,143			28,143
Accumulated depreciation	$ (14,090)			(14,090)
Date of construction	1979
Date acquired	Jun-97
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 28,143
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 14,090
Unencumbered Apartment Communities [Member] | Kings Road [Member] | Los Angeles, CA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	3 years
Unencumbered Apartment Communities [Member] | Kings Road [Member] | Los Angeles, CA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Unencumbered Apartment Communities [Member] | Lafayette Highlands [Member] | Lafayette, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	150
Initial cost [Abstract]
Land				17,774
Buildings and improvements				41,473
Costs capitalized subsequent to acquisition				2,065
Gross amount carried at close of period [Abstract]
Land and improvements				17,774
Buildings and improvements				43,538
Total	$ 61,312			61,312
Accumulated depreciation	$ (6,023)			(6,023)
Date of construction	1973
Date acquired	Apr-14
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 61,312
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 6,023
Unencumbered Apartment Communities [Member] | Lafayette Highlands [Member] | Lafayette, CA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	5 years
Unencumbered Apartment Communities [Member] | Lafayette Highlands [Member] | Lafayette, CA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Unencumbered Apartment Communities [Member] | Lakeshore Landing [Member] | San Mateo, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	308
Initial cost [Abstract]
Land				38,155
Buildings and improvements				89,028
Costs capitalized subsequent to acquisition				5,920
Gross amount carried at close of period [Abstract]
Land and improvements				38,155
Buildings and improvements				94,948
Total	$ 133,103			133,103
Accumulated depreciation	$ (14,103)			(14,103)
Date of construction	1988
Date acquired	Apr-14
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 133,103
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 14,103
Unencumbered Apartment Communities [Member] | Lakeshore Landing [Member] | San Mateo, CA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	5 years
Unencumbered Apartment Communities [Member] | Lakeshore Landing [Member] | San Mateo, CA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Unencumbered Apartment Communities [Member] | Laurels at Mill Creek [Member] | Mill Creek, WA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	164
Initial cost [Abstract]
Land				1,559
Buildings and improvements				6,430
Costs capitalized subsequent to acquisition				6,231
Gross amount carried at close of period [Abstract]
Land and improvements				1,595
Buildings and improvements				12,625
Total	$ 14,220			14,220
Accumulated depreciation	$ (9,082)			(9,082)
Date of construction	1981
Date acquired	Dec-96
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 14,220
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 9,082
Unencumbered Apartment Communities [Member] | Laurels at Mill Creek [Member] | Mill Creek, WA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	3 years
Unencumbered Apartment Communities [Member] | Laurels at Mill Creek [Member] | Mill Creek, WA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Unencumbered Apartment Communities [Member] | Lawrence Station [Member] | Sunnyvale, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	336
Initial cost [Abstract]
Land				45,532
Buildings and improvements				106,735
Costs capitalized subsequent to acquisition				1,100
Gross amount carried at close of period [Abstract]
Land and improvements				45,532
Buildings and improvements				107,835
Total	$ 153,367			153,367
Accumulated depreciation	$ (18,224)			(18,224)
Date of construction	2012
Date acquired	Apr-14
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 153,367
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 18,224
Unencumbered Apartment Communities [Member] | Lawrence Station [Member] | Sunnyvale, CA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	5 years
Unencumbered Apartment Communities [Member] | Lawrence Station [Member] | Sunnyvale, CA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Unencumbered Apartment Communities [Member] | Le Parc [Member] | Santa Clara, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	140
Initial cost [Abstract]
Land				3,090
Buildings and improvements				7,421
Costs capitalized subsequent to acquisition				11,787
Gross amount carried at close of period [Abstract]
Land and improvements				3,092
Buildings and improvements				19,206
Total	$ 22,298			22,298
Accumulated depreciation	$ (14,464)			(14,464)
Date of construction	1975
Date acquired	Feb-94
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 22,298
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 14,464
Unencumbered Apartment Communities [Member] | Le Parc [Member] | Santa Clara, CA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	3 years
Unencumbered Apartment Communities [Member] | Le Parc [Member] | Santa Clara, CA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Unencumbered Apartment Communities [Member] | Marbrisa [Member] | Long Beach, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	202
Initial cost [Abstract]
Land				4,700
Buildings and improvements				18,605
Costs capitalized subsequent to acquisition				8,640
Gross amount carried at close of period [Abstract]
Land and improvements				4,760
Buildings and improvements				27,185
Total	$ 31,945			31,945
Accumulated depreciation	$ (13,889)			(13,889)
Date of construction	1987
Date acquired	Sep-02
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 31,945
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 13,889
Unencumbered Apartment Communities [Member] | Marbrisa [Member] | Long Beach, CA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	3 years
Unencumbered Apartment Communities [Member] | Marbrisa [Member] | Long Beach, CA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Unencumbered Apartment Communities [Member] | Marina City Club [Member] | Marina Del Rey, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	101
Initial cost [Abstract]
Land				0
Buildings and improvements				28,167
Costs capitalized subsequent to acquisition				27,613
Gross amount carried at close of period [Abstract]
Land and improvements				0
Buildings and improvements				55,780
Total	$ 55,780			55,780
Accumulated depreciation	$ (23,105)			(23,105)
Date of construction	1971
Date acquired	Jan-04
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 55,780
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 23,105
Unencumbered Apartment Communities [Member] | Marina City Club [Member] | Marina Del Rey, CA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	3 years
Unencumbered Apartment Communities [Member] | Marina City Club [Member] | Marina Del Rey, CA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Unencumbered Apartment Communities [Member] | Marina Cove [Member] | Santa Clara, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	292
Initial cost [Abstract]
Land				5,320
Buildings and improvements				16,431
Costs capitalized subsequent to acquisition				14,699
Gross amount carried at close of period [Abstract]
Land and improvements				5,324
Buildings and improvements				31,126
Total	$ 36,450			36,450
Accumulated depreciation	$ (22,342)			(22,342)
Date of construction	1974
Date acquired	Jun-94
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 36,450
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 22,342
Unencumbered Apartment Communities [Member] | Marina Cove [Member] | Santa Clara, CA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	3 years
Unencumbered Apartment Communities [Member] | Marina Cove [Member] | Santa Clara, CA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Unencumbered Apartment Communities [Member] | Mariner's Place [Member] | Oxnard, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	105
Initial cost [Abstract]
Land				1,555
Buildings and improvements				6,103
Costs capitalized subsequent to acquisition				2,314
Gross amount carried at close of period [Abstract]
Land and improvements				1,562
Buildings and improvements				8,410
Total	$ 9,972			9,972
Accumulated depreciation	$ (5,316)			(5,316)
Date of construction	1987
Date acquired	May-00
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 9,972
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 5,316
Unencumbered Apartment Communities [Member] | Mariner's Place [Member] | Oxnard, CA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	3 years
Unencumbered Apartment Communities [Member] | Mariner's Place [Member] | Oxnard, CA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Unencumbered Apartment Communities [Member] | MB 360 [Member] | San Francisco, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	360
Initial cost [Abstract]
Land				21,421
Buildings and improvements				114,376
Costs capitalized subsequent to acquisition				122,654
Gross amount carried at close of period [Abstract]
Land and improvements				42,001
Buildings and improvements				216,450
Total	$ 258,451			258,451
Accumulated depreciation	$ (21,619)			(21,619)
Date of construction	2014
Date acquired	Apr-14
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 258,451
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 21,619
Unencumbered Apartment Communities [Member] | MB 360 [Member] | San Francisco, CA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	3 years
Unencumbered Apartment Communities [Member] | MB 360 [Member] | San Francisco, CA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Unencumbered Apartment Communities [Member] | Mesa Village [Member] | Clairemont, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	133
Initial cost [Abstract]
Land				1,888
Buildings and improvements				7,498
Costs capitalized subsequent to acquisition				1,730
Gross amount carried at close of period [Abstract]
Land and improvements				1,894
Buildings and improvements				9,222
Total	$ 11,116			11,116
Accumulated depreciation	$ (4,691)			(4,691)
Date of construction	1963
Date acquired	Dec-02
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 11,116
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 4,691
Unencumbered Apartment Communities [Member] | Mesa Village [Member] | Clairemont, CA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	3 years
Unencumbered Apartment Communities [Member] | Mesa Village [Member] | Clairemont, CA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Unencumbered Apartment Communities [Member] | Mio [Member] | San Jose, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	103
Initial cost [Abstract]
Land				11,012
Buildings and improvements				39,982
Costs capitalized subsequent to acquisition				367
Gross amount carried at close of period [Abstract]
Land and improvements				11,012
Buildings and improvements				40,349
Total	$ 51,361			51,361
Accumulated depreciation	$ (2,786)			(2,786)
Date of construction	2015
Date acquired	Jan-16
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 51,361
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 2,786
Unencumbered Apartment Communities [Member] | Mio [Member] | San Jose, CA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	3 years
Unencumbered Apartment Communities [Member] | Mio [Member] | San Jose, CA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Unencumbered Apartment Communities [Member] | Mira Monte [Member] | Mira Mesa, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	354
Initial cost [Abstract]
Land				7,165
Buildings and improvements				28,459
Costs capitalized subsequent to acquisition				10,588
Gross amount carried at close of period [Abstract]
Land and improvements				7,186
Buildings and improvements				39,026
Total	$ 46,212			46,212
Accumulated depreciation	$ (22,220)			(22,220)
Date of construction	1982
Date acquired	Dec-02
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 46,212
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 22,220
Unencumbered Apartment Communities [Member] | Mira Monte [Member] | Mira Mesa, CA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	3 years
Unencumbered Apartment Communities [Member] | Mira Monte [Member] | Mira Mesa, CA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Unencumbered Apartment Communities [Member] | Miracle Mile Marbella [Member] | Los Angeles, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	236
Initial cost [Abstract]
Land				7,791
Buildings and improvements				23,075
Costs capitalized subsequent to acquisition				14,330
Gross amount carried at close of period [Abstract]
Land and improvements				7,886
Buildings and improvements				37,310
Total	$ 45,196			45,196
Accumulated depreciation	$ (24,621)			(24,621)
Date of construction	1988
Date acquired	Aug-97
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 45,196
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 24,621
Unencumbered Apartment Communities [Member] | Miracle Mile Marbella [Member] | Los Angeles, CA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	3 years
Unencumbered Apartment Communities [Member] | Miracle Mile Marbella [Member] | Los Angeles, CA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Unencumbered Apartment Communities [Member] | Mission Hills [Member] | Oceanside, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	282
Initial cost [Abstract]
Land				10,099
Buildings and improvements				38,778
Costs capitalized subsequent to acquisition				6,780
Gross amount carried at close of period [Abstract]
Land and improvements				10,167
Buildings and improvements				45,490
Total	$ 55,657			55,657
Accumulated depreciation	$ (20,326)			(20,326)
Date of construction	1984
Date acquired	Jul-05
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 55,657
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 20,326
Unencumbered Apartment Communities [Member] | Mission Hills [Member] | Oceanside, CA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	3 years
Unencumbered Apartment Communities [Member] | Mission Hills [Member] | Oceanside, CA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Unencumbered Apartment Communities [Member] | Mission Peaks [Member] | Fremont, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	453
Initial cost [Abstract]
Land				46,499
Buildings and improvements				108,498
Costs capitalized subsequent to acquisition				3,457
Gross amount carried at close of period [Abstract]
Land and improvements				46,499
Buildings and improvements				111,955
Total	$ 158,454			158,454
Accumulated depreciation	$ (15,669)			(15,669)
Date of construction	1995
Date acquired	Apr-14
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 158,454
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 15,669
Unencumbered Apartment Communities [Member] | Mission Peaks [Member] | Fremont, CA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	5 years
Unencumbered Apartment Communities [Member] | Mission Peaks [Member] | Fremont, CA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Unencumbered Apartment Communities [Member] | Mission Peaks II [Member] | Fremont, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	336
Initial cost [Abstract]
Land				31,429
Buildings and improvements				73,334
Costs capitalized subsequent to acquisition				4,469
Gross amount carried at close of period [Abstract]
Land and improvements				31,429
Buildings and improvements				77,803
Total	$ 109,232			109,232
Accumulated depreciation	$ (11,188)			(11,188)
Date of construction	1989
Date acquired	Apr-14
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 109,232
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 11,188
Unencumbered Apartment Communities [Member] | Mission Peaks II [Member] | Fremont, CA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	5 years
Unencumbered Apartment Communities [Member] | Mission Peaks II [Member] | Fremont, CA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Unencumbered Apartment Communities [Member] | Monterey Villas [Member] | Oxnard, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	122
Initial cost [Abstract]
Land				2,349
Buildings and improvements				5,579
Costs capitalized subsequent to acquisition				6,410
Gross amount carried at close of period [Abstract]
Land and improvements				2,424
Buildings and improvements				11,914
Total	$ 14,338			14,338
Accumulated depreciation	$ (7,386)			(7,386)
Date of construction	1974
Date acquired	Jul-97
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 14,338
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 7,386
Unencumbered Apartment Communities [Member] | Monterey Villas [Member] | Oxnard, CA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	3 years
Unencumbered Apartment Communities [Member] | Monterey Villas [Member] | Oxnard, CA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Unencumbered Apartment Communities [Member] | Muse [Member] | Los Angeles, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	152
Initial cost [Abstract]
Land				7,822
Buildings and improvements				33,436
Costs capitalized subsequent to acquisition				2,724
Gross amount carried at close of period [Abstract]
Land and improvements				7,823
Buildings and improvements				36,159
Total	$ 43,982			43,982
Accumulated depreciation	$ (11,275)			(11,275)
Date of construction	2011
Date acquired	Feb-11
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 43,982
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 11,275
Unencumbered Apartment Communities [Member] | Muse [Member] | Hollywood, CA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	3 years
Unencumbered Apartment Communities [Member] | Muse [Member] | Hollywood, CA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Unencumbered Apartment Communities [Member] | Museum Park [Member] | San Jose, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	117
Initial cost [Abstract]
Land				13,864
Buildings and improvements				32,348
Costs capitalized subsequent to acquisition				1,236
Gross amount carried at close of period [Abstract]
Land and improvements				13,864
Buildings and improvements				33,584
Total	$ 47,448			47,448
Accumulated depreciation	$ (4,777)			(4,777)
Date of construction	2002
Date acquired	Apr-14
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 47,448
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 4,777
Unencumbered Apartment Communities [Member] | Museum Park [Member] | San Jose, CA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	5 years
Unencumbered Apartment Communities [Member] | Museum Park [Member] | San Jose, CA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Unencumbered Apartment Communities [Member] | Membership Interest In Palm Valley [Member] | San Jose, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	1,098
Initial cost [Abstract]
Land				133,802
Buildings and improvements				312,205
Costs capitalized subsequent to acquisition				2,035
Gross amount carried at close of period [Abstract]
Land and improvements				133,802
Buildings and improvements				314,240
Total	$ 448,042			448,042
Accumulated depreciation	$ (10,741)			(10,741)
Date of construction	2008
Date acquired	Jan-17
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 448,042
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 10,741
Unencumbered Apartment Communities [Member] | Membership Interest In Palm Valley [Member] | San Jose, CA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	3 years
Unencumbered Apartment Communities [Member] | Membership Interest In Palm Valley [Member] | San Jose, CA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Unencumbered Apartment Communities [Member] | Paragon Apartments [Member] | Fremont, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	301
Initial cost [Abstract]
Land				32,230
Buildings and improvements				77,320
Costs capitalized subsequent to acquisition				1,367
Gross amount carried at close of period [Abstract]
Land and improvements				32,230
Buildings and improvements				78,687
Total	$ 110,917			110,917
Accumulated depreciation	$ (9,136)			(9,136)
Date of construction	2013
Date acquired	Jul-14
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 110,917
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 9,136
Unencumbered Apartment Communities [Member] | Paragon Apartments [Member] | Fremont, CA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	3 years
Unencumbered Apartment Communities [Member] | Paragon Apartments [Member] | Fremont, CA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Unencumbered Apartment Communities [Member] | Park Catalina [Member] | Los Angeles, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	90
Initial cost [Abstract]
Land				4,710
Buildings and improvements				18,839
Costs capitalized subsequent to acquisition				3,068
Gross amount carried at close of period [Abstract]
Land and improvements				4,710
Buildings and improvements				21,907
Total	$ 26,617			26,617
Accumulated depreciation	$ (4,823)			(4,823)
Date of construction	2002
Date acquired	Jun-12
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 26,617
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 4,823
Unencumbered Apartment Communities [Member] | Park Catalina [Member] | Los Angeles, CA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	3 years
Unencumbered Apartment Communities [Member] | Park Catalina [Member] | Los Angeles, CA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Unencumbered Apartment Communities [Member] | Park Viridian [Member] | Anaheim, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	320
Initial cost [Abstract]
Land				15,894
Buildings and improvements				63,574
Costs capitalized subsequent to acquisition				3,023
Gross amount carried at close of period [Abstract]
Land and improvements				15,894
Buildings and improvements				66,597
Total	$ 82,491			82,491
Accumulated depreciation	$ (9,304)			(9,304)
Date of construction	2008
Date acquired	Apr-14
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 82,491
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 9,304
Unencumbered Apartment Communities [Member] | Park Viridian [Member] | Anaheim, CA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	5 years
Unencumbered Apartment Communities [Member] | Park Viridian [Member] | Anaheim, CA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Unencumbered Apartment Communities [Member] | Park West [Member] | San Francisco, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	126
Initial cost [Abstract]
Land				9,424
Buildings and improvements				21,988
Costs capitalized subsequent to acquisition				11,930
Gross amount carried at close of period [Abstract]
Land and improvements				9,424
Buildings and improvements				33,918
Total	$ 43,342			43,342
Accumulated depreciation	$ (7,730)			(7,730)
Date of construction	1958
Date acquired	Sep-12
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 43,342
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 7,730
Unencumbered Apartment Communities [Member] | Park West [Member] | San Francisco, CA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	3 years
Unencumbered Apartment Communities [Member] | Park West [Member] | San Francisco, CA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Unencumbered Apartment Communities [Member] | Parkwood at Mill Creek [Member] | Mill Creek, WA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	240
Initial cost [Abstract]
Land				10,680
Buildings and improvements				42,722
Costs capitalized subsequent to acquisition				2,441
Gross amount carried at close of period [Abstract]
Land and improvements				10,680
Buildings and improvements				45,163
Total	$ 55,843			55,843
Accumulated depreciation	$ (6,492)			(6,492)
Date of construction	1989
Date acquired	Apr-14
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 55,843
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 6,492
Unencumbered Apartment Communities [Member] | Parkwood at Mill Creek [Member] | Mill Creek, WA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	5 years
Unencumbered Apartment Communities [Member] | Parkwood at Mill Creek [Member] | Mill Creek, WA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Unencumbered Apartment Communities [Member] | Pathways at Bixby Village [Member] | Long Beach, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	296
Initial cost [Abstract]
Land				4,083
Buildings and improvements				16,757
Costs capitalized subsequent to acquisition				20,235
Gross amount carried at close of period [Abstract]
Land and improvements				6,239
Buildings and improvements				34,836
Total	$ 41,075			41,075
Accumulated depreciation	$ (29,186)			(29,186)
Date of construction	1975
Date acquired	Feb-91
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 41,075
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 29,186
Unencumbered Apartment Communities [Member] | Pathways at Bixby Village [Member] | Long Beach, CA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	3 years
Unencumbered Apartment Communities [Member] | Pathways at Bixby Village [Member] | Long Beach, CA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Unencumbered Apartment Communities [Member] | Piedmont [Member] | Bellevue, WA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	396
Initial cost [Abstract]
Land				19,848
Buildings and improvements				59,606
Costs capitalized subsequent to acquisition				11,186
Gross amount carried at close of period [Abstract]
Land and improvements				19,848
Buildings and improvements				70,792
Total	$ 90,640			90,640
Accumulated depreciation	$ (9,660)			(9,660)
Date of construction	1969
Date acquired	May-14
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 90,640
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 9,660
Unencumbered Apartment Communities [Member] | Piedmont [Member] | Bellevue, WA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	3 years
Unencumbered Apartment Communities [Member] | Piedmont [Member] | Bellevue, WA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Unencumbered Apartment Communities [Member] | Pinehurst [Member] | Ventura, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	28
Initial cost [Abstract]
Land				0
Buildings and improvements				1,711
Costs capitalized subsequent to acquisition				548
Gross amount carried at close of period [Abstract]
Land and improvements				0
Buildings and improvements				2,259
Total	$ 2,259			2,259
Accumulated depreciation	$ (1,249)			(1,249)
Date of construction	1973
Date acquired	Dec-04
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 2,259
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 1,249
Unencumbered Apartment Communities [Member] | Pinehurst [Member] | Ventura, CA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	3 years
Unencumbered Apartment Communities [Member] | Pinehurst [Member] | Ventura, CA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	24 years
Unencumbered Apartment Communities [Member] | Pinnacle Sonata [Member] | Bothell, WA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	268
Initial cost [Abstract]
Land				14,647
Buildings and improvements				58,586
Costs capitalized subsequent to acquisition				2,602
Gross amount carried at close of period [Abstract]
Land and improvements				14,647
Buildings and improvements				61,188
Total	$ 75,835			75,835
Accumulated depreciation	$ (8,496)			(8,496)
Date of construction	2000
Date acquired	Apr-14
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 75,835
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 8,496
Unencumbered Apartment Communities [Member] | Pinnacle Sonata [Member] | Bothell, WA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	5 years
Unencumbered Apartment Communities [Member] | Pinnacle Sonata [Member] | Bothell, WA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Unencumbered Apartment Communities [Member] | Pointe at Cupertinoe [Member] | Cupertino, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	116
Initial cost [Abstract]
Land				4,505
Buildings and improvements				17,605
Costs capitalized subsequent to acquisition				11,908
Gross amount carried at close of period [Abstract]
Land and improvements				4,505
Buildings and improvements				29,513
Total	$ 34,018			34,018
Accumulated depreciation	$ (15,789)			(15,789)
Date of construction	1963
Date acquired	Aug-98
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 34,018
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 15,789
Unencumbered Apartment Communities [Member] | Pointe at Cupertinoe [Member] | Cupertino, CA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	3 years
Unencumbered Apartment Communities [Member] | Pointe at Cupertinoe [Member] | Cupertino, CA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Unencumbered Apartment Communities [Member] | Radius [Member] | Redwood City, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	264
Initial cost [Abstract]
Land				11,702
Buildings and improvements				152,336
Costs capitalized subsequent to acquisition				18
Gross amount carried at close of period [Abstract]
Land and improvements				11,702
Buildings and improvements				152,354
Total	$ 164,056			164,056
Accumulated depreciation	$ (20,701)			(20,701)
Date of construction	2015
Date acquired	Apr-14
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 164,056
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 20,701
Unencumbered Apartment Communities [Member] | Radius [Member] | Redwood City, CA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	3 years
Unencumbered Apartment Communities [Member] | Radius [Member] | Redwood City, CA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Unencumbered Apartment Communities [Member] | Reed Square [Member] | Sunnyvale, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	100
Initial cost [Abstract]
Land				6,873
Buildings and improvements				16,037
Costs capitalized subsequent to acquisition				8,023
Gross amount carried at close of period [Abstract]
Land and improvements				6,873
Buildings and improvements				24,060
Total	$ 30,933			30,933
Accumulated depreciation	$ (7,372)			(7,372)
Date of construction	1970
Date acquired	Jan-12
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 30,933
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 7,372
Unencumbered Apartment Communities [Member] | Reed Square [Member] | Sunnyvale, CA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	3 years
Unencumbered Apartment Communities [Member] | Reed Square [Member] | Sunnyvale, CA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Unencumbered Apartment Communities [Member] | Regency at Encino [Member] | Encino, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	75
Initial cost [Abstract]
Land				3,184
Buildings and improvements				12,737
Costs capitalized subsequent to acquisition				3,312
Gross amount carried at close of period [Abstract]
Land and improvements				3,184
Buildings and improvements				16,049
Total	$ 19,233			19,233
Accumulated depreciation	$ (5,377)			(5,377)
Date of construction	1989
Date acquired	Dec-09
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 19,233
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 5,377
Unencumbered Apartment Communities [Member] | Regency at Encino [Member] | Encino, CA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	3 years
Unencumbered Apartment Communities [Member] | Regency at Encino [Member] | Encino, CA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Unencumbered Apartment Communities [Member] | Renaissance at Uptown Orange [Member] | Orange, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	460
Initial cost [Abstract]
Land				27,870
Buildings and improvements				111,482
Costs capitalized subsequent to acquisition				4,122
Gross amount carried at close of period [Abstract]
Land and improvements				27,870
Buildings and improvements				115,604
Total	$ 143,474			143,474
Accumulated depreciation	$ (16,189)			(16,189)
Date of construction	2007
Date acquired	Apr-14
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 143,474
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 16,189
Unencumbered Apartment Communities [Member] | Renaissance at Uptown Orange [Member] | Orange, CA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	5 years
Unencumbered Apartment Communities [Member] | Renaissance at Uptown Orange [Member] | Orange, CA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Unencumbered Apartment Communities [Member] | The Reveal [Member] | Woodland Hills, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	438
Initial cost [Abstract]
Land				25,073
Buildings and improvements				121,314
Costs capitalized subsequent to acquisition				1,104
Gross amount carried at close of period [Abstract]
Land and improvements				25,073
Buildings and improvements				122,418
Total	$ 147,491			147,491
Accumulated depreciation	$ (12,990)			(12,990)
Date of construction	2010
Date acquired	Apr-15
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 147,491
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 12,990
Unencumbered Apartment Communities [Member] | The Reveal [Member] | Woodland Hills, CA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	3 years
Unencumbered Apartment Communities [Member] | The Reveal [Member] | Woodland Hills, CA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Unencumbered Apartment Communities [Member] | Salmon Run at Perry Creek [Member] | Bothell, WA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	132
Initial cost [Abstract]
Land				3,717
Buildings and improvements				11,483
Costs capitalized subsequent to acquisition				2,018
Gross amount carried at close of period [Abstract]
Land and improvements				3,801
Buildings and improvements				13,417
Total	$ 17,218			17,218
Accumulated depreciation	$ (7,639)			(7,639)
Date of construction	2000
Date acquired	Oct-00
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 17,218
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 7,639
Unencumbered Apartment Communities [Member] | Salmon Run at Perry Creek [Member] | Bothell, WA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	3 years
Unencumbered Apartment Communities [Member] | Salmon Run at Perry Creek [Member] | Bothell, WA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Unencumbered Apartment Communities [Member] | Sammamish View [Member] | Bellevue, WA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	153
Initial cost [Abstract]
Land				3,324
Buildings and improvements				7,501
Costs capitalized subsequent to acquisition				6,660
Gross amount carried at close of period [Abstract]
Land and improvements				3,331
Buildings and improvements				14,154
Total	$ 17,485			17,485
Accumulated depreciation	$ (11,623)			(11,623)
Date of construction	1986
Date acquired	Nov-94
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 17,485
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 11,623
Unencumbered Apartment Communities [Member] | Sammamish View [Member] | Bellevue, WA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	3 years
Unencumbered Apartment Communities [Member] | Sammamish View [Member] | Bellevue, WA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Unencumbered Apartment Communities [Member] | 101 San Fernando [Member] | San Jose, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	323
Initial cost [Abstract]
Land				4,173
Buildings and improvements				58,961
Costs capitalized subsequent to acquisition				10,473
Gross amount carried at close of period [Abstract]
Land and improvements				4,173
Buildings and improvements				69,434
Total	$ 73,607			73,607
Accumulated depreciation	$ (20,152)			(20,152)
Date of construction	2001
Date acquired	Jul-10
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 73,607
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 20,152
Unencumbered Apartment Communities [Member] | 101 San Fernando [Member] | San Jose, CA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	3 years
Unencumbered Apartment Communities [Member] | 101 San Fernando [Member] | San Jose, CA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Unencumbered Apartment Communities [Member] | San Marcos [Member] | Richmond, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	432
Initial cost [Abstract]
Land				15,563
Buildings and improvements				36,204
Costs capitalized subsequent to acquisition				30,439
Gross amount carried at close of period [Abstract]
Land and improvements				22,866
Buildings and improvements				59,340
Total	$ 82,206			82,206
Accumulated depreciation	$ (28,461)			(28,461)
Date of construction	2003
Date acquired	Nov-03
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 82,206
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 28,461
Unencumbered Apartment Communities [Member] | San Marcos [Member] | Richmond, CA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	3 years
Unencumbered Apartment Communities [Member] | San Marcos [Member] | Richmond, CA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Unencumbered Apartment Communities [Member] | Santee Court/Santee Village [Member] | Los Angeles, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	238
Initial cost [Abstract]
Land				9,581
Buildings and improvements				40,317
Costs capitalized subsequent to acquisition				6,383
Gross amount carried at close of period [Abstract]
Land and improvements				9,582
Buildings and improvements				46,699
Total	$ 56,281			56,281
Accumulated depreciation	$ (12,474)			(12,474)
Date of construction	2004
Date acquired	Oct-10
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 56,281
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 12,474
Unencumbered Apartment Communities [Member] | Santee Court/Santee Village [Member] | Los Angeles, CA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	3 years
Unencumbered Apartment Communities [Member] | Santee Court/Santee Village [Member] | Los Angeles, CA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Unencumbered Apartment Communities [Member] | Shadow Point [Member] | Spring Valley, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	172
Initial cost [Abstract]
Land				2,812
Buildings and improvements				11,170
Costs capitalized subsequent to acquisition				3,407
Gross amount carried at close of period [Abstract]
Land and improvements				2,820
Buildings and improvements				14,569
Total	$ 17,389			17,389
Accumulated depreciation	$ (7,412)			(7,412)
Date of construction	1983
Date acquired	Dec-02
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 17,389
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 7,412
Unencumbered Apartment Communities [Member] | Shadow Point [Member] | Spring Valley, CA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	3 years
Unencumbered Apartment Communities [Member] | Shadow Point [Member] | Spring Valley, CA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Unencumbered Apartment Communities [Member] | Shadowbrook [Member] | Redmond, WA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	418
Initial cost [Abstract]
Land				19,292
Buildings and improvements				77,168
Costs capitalized subsequent to acquisition				3,892
Gross amount carried at close of period [Abstract]
Land and improvements				19,292
Buildings and improvements				81,060
Total	$ 100,352			100,352
Accumulated depreciation	$ (11,419)			(11,419)
Date of construction	1986
Date acquired	Apr-14
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 100,352
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 11,419
Unencumbered Apartment Communities [Member] | Shadowbrook [Member] | Redmond, WA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	5 years
Unencumbered Apartment Communities [Member] | Shadowbrook [Member] | Redmond, WA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Unencumbered Apartment Communities [Member] | Slater 116 [Member] | Kirkland, WA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	108
Initial cost [Abstract]
Land				7,379
Buildings and improvements				22,138
Costs capitalized subsequent to acquisition				709
Gross amount carried at close of period [Abstract]
Land and improvements				7,379
Buildings and improvements				22,847
Total	$ 30,226			30,226
Accumulated depreciation	$ (3,446)			(3,446)
Date of construction	2013
Date acquired	Sep-13
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 30,226
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 3,446
Unencumbered Apartment Communities [Member] | Slater 116 [Member] | Kirkland, WA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	3 years
Unencumbered Apartment Communities [Member] | Slater 116 [Member] | Kirkland, WA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Unencumbered Apartment Communities [Member] | Solstice [Member] | Sunnyvale, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	280
Initial cost [Abstract]
Land				34,444
Buildings and improvements				147,262
Costs capitalized subsequent to acquisition				4,598
Gross amount carried at close of period [Abstract]
Land and improvements				34,444
Buildings and improvements				151,860
Total	$ 186,304			186,304
Accumulated depreciation	$ (24,629)			(24,629)
Date of construction	2014
Date acquired	Apr-14
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 186,304
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 24,629
Unencumbered Apartment Communities [Member] | Solstice [Member] | Sunnyvale, CA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	5 years
Unencumbered Apartment Communities [Member] | Solstice [Member] | Sunnyvale, CA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Unencumbered Apartment Communities [Member] | Stonehedge Village [Member] | Bothell, WA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	196
Initial cost [Abstract]
Land				3,167
Buildings and improvements				12,603
Costs capitalized subsequent to acquisition				6,516
Gross amount carried at close of period [Abstract]
Land and improvements				3,201
Buildings and improvements				19,085
Total	$ 22,286			22,286
Accumulated depreciation	$ (12,875)			(12,875)
Date of construction	1986
Date acquired	Oct-97
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 22,286
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 12,875
Unencumbered Apartment Communities [Member] | Stonehedge Village [Member] | Bothell, WA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	3 years
Unencumbered Apartment Communities [Member] | Stonehedge Village [Member] | Bothell, WA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Unencumbered Apartment Communities [Member] | Summit Park [Member] | San Diego, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	300
Initial cost [Abstract]
Land				5,959
Buildings and improvements				23,670
Costs capitalized subsequent to acquisition				5,915
Gross amount carried at close of period [Abstract]
Land and improvements				5,977
Buildings and improvements				29,567
Total	$ 35,544			35,544
Accumulated depreciation	$ (15,594)			(15,594)
Date of construction	1972
Date acquired	Dec-02
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 35,544
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 15,594
Unencumbered Apartment Communities [Member] | Summit Park [Member] | San Diego, CA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	3 years
Unencumbered Apartment Communities [Member] | Summit Park [Member] | San Diego, CA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Unencumbered Apartment Communities [Member] | Taylor 28 [Member] | Seattle, WA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	197
Initial cost [Abstract]
Land				13,915
Buildings and improvements				57,700
Costs capitalized subsequent to acquisition				1,892
Gross amount carried at close of period [Abstract]
Land and improvements				13,915
Buildings and improvements				59,592
Total	$ 73,507			73,507
Accumulated depreciation	$ (8,120)			(8,120)
Date of construction	2008
Date acquired	Apr-14
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 73,507
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 8,120
Unencumbered Apartment Communities [Member] | Taylor 28 [Member] | Seattle, WA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	5 years
Unencumbered Apartment Communities [Member] | Taylor 28 [Member] | Seattle, WA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Unencumbered Apartment Communities [Member] | The Avery [Member] | Los Angeles, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	121
Initial cost [Abstract]
Land				6,964
Buildings and improvements				29,922
Costs capitalized subsequent to acquisition				299
Gross amount carried at close of period [Abstract]
Land and improvements				6,964
Buildings and improvements				30,221
Total	$ 37,185			37,185
Accumulated depreciation	$ (3,810)			(3,810)
Date of construction	2014
Date acquired	Mar-14
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 37,185
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 3,810
Unencumbered Apartment Communities [Member] | The Avery [Member] | Anaheim, CA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	3 years
Unencumbered Apartment Communities [Member] | The Avery [Member] | Anaheim, CA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Unencumbered Apartment Communities [Member] | The Cairns [Member] | Seattle, WA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	99
Initial cost [Abstract]
Land				6,937
Buildings and improvements				20,679
Costs capitalized subsequent to acquisition				1,459
Gross amount carried at close of period [Abstract]
Land and improvements				6,939
Buildings and improvements				22,136
Total	$ 29,075			29,075
Accumulated depreciation	$ (8,056)			(8,056)
Date of construction	2006
Date acquired	Jun-07
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 29,075
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 8,056
Unencumbered Apartment Communities [Member] | The Cairns [Member] | Seattle, WA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	3 years
Unencumbered Apartment Communities [Member] | The Cairns [Member] | Seattle, WA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Unencumbered Apartment Communities [Member] | The Commons [Member] | Campbell, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	264
Initial cost [Abstract]
Land				12,555
Buildings and improvements				29,307
Costs capitalized subsequent to acquisition				7,370
Gross amount carried at close of period [Abstract]
Land and improvements				12,556
Buildings and improvements				36,676
Total	$ 49,232			49,232
Accumulated depreciation	$ (10,676)			(10,676)
Date of construction	1973
Date acquired	Jul-10
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 49,232
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 10,676
Unencumbered Apartment Communities [Member] | The Commons [Member] | Campbell, CA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	3 years
Unencumbered Apartment Communities [Member] | The Commons [Member] | Campbell, CA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Unencumbered Apartment Communities [Member] | The Elliot at Mukilteo [Member] | Mukilteo, WA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	301
Initial cost [Abstract]
Land				2,498
Buildings and improvements				10,595
Costs capitalized subsequent to acquisition				15,566
Gross amount carried at close of period [Abstract]
Land and improvements				2,824
Buildings and improvements				25,835
Total	$ 28,659			28,659
Accumulated depreciation	$ (18,311)			(18,311)
Date of construction	1981
Date acquired	Jan-97
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 28,659
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 18,311
Unencumbered Apartment Communities [Member] | The Elliot at Mukilteo [Member] | Mukilteo, WA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	3 years
Unencumbered Apartment Communities [Member] | The Elliot at Mukilteo [Member] | Mukilteo, WA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Unencumbered Apartment Communities [Member] | The Grand [Member] | Oakland, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	243
Initial cost [Abstract]
Land				4,531
Buildings and improvements				89,208
Costs capitalized subsequent to acquisition				6,100
Gross amount carried at close of period [Abstract]
Land and improvements				4,531
Buildings and improvements				95,308
Total	$ 99,839			99,839
Accumulated depreciation	$ (30,858)			(30,858)
Date of construction	2009
Date acquired	Jan-09
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 99,839
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 30,858
Unencumbered Apartment Communities [Member] | The Grand [Member] | Oakland, CA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	3 years
Unencumbered Apartment Communities [Member] | The Grand [Member] | Oakland, CA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Unencumbered Apartment Communities [Member] | The Hallie [Member] | Pasadena, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	292
Initial cost [Abstract]
Land				2,202
Buildings and improvements				4,794
Costs capitalized subsequent to acquisition				53,126
Gross amount carried at close of period [Abstract]
Land and improvements				8,385
Buildings and improvements				51,737
Total	$ 60,122			60,122
Accumulated depreciation	$ (26,284)			(26,284)
Date of construction	1972
Date acquired	Apr-97
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 60,122
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 26,284
Unencumbered Apartment Communities [Member] | The Hallie [Member] | Pasadena, CA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	3 years
Unencumbered Apartment Communities [Member] | The Hallie [Member] | Pasadena, CA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Unencumbered Apartment Communities [Member] | The Lofts at Pinehurst [Member] | Ventura, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	118
Initial cost [Abstract]
Land				1,570
Buildings and improvements				3,912
Costs capitalized subsequent to acquisition				5,029
Gross amount carried at close of period [Abstract]
Land and improvements				1,618
Buildings and improvements				8,893
Total	$ 10,511			10,511
Accumulated depreciation	$ (5,311)			(5,311)
Date of construction	1971
Date acquired	Jun-97
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 10,511
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 5,311
Unencumbered Apartment Communities [Member] | The Lofts at Pinehurst [Member] | Ventura, CA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	3 years
Unencumbered Apartment Communities [Member] | The Lofts at Pinehurst [Member] | Ventura, CA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Unencumbered Apartment Communities [Member] | The Stuart [Member] | Pasadena, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	188
Initial cost [Abstract]
Land				13,574
Buildings and improvements				54,298
Costs capitalized subsequent to acquisition				2,107
Gross amount carried at close of period [Abstract]
Land and improvements				13,574
Buildings and improvements				56,405
Total	$ 69,979			69,979
Accumulated depreciation	$ (8,211)			(8,211)
Date of construction	2007
Date acquired	Apr-14
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 69,979
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 8,211
Unencumbered Apartment Communities [Member] | The Stuart [Member] | Pasadena, CA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	5 years
Unencumbered Apartment Communities [Member] | The Stuart [Member] | Pasadena, CA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Unencumbered Apartment Communities [Member] | The Trails of Redmond [Member] | Redmond, WA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	423
Initial cost [Abstract]
Land				21,930
Buildings and improvements				87,720
Costs capitalized subsequent to acquisition				3,693
Gross amount carried at close of period [Abstract]
Land and improvements				21,930
Buildings and improvements				91,413
Total	$ 113,343			113,343
Accumulated depreciation	$ (12,928)			(12,928)
Date of construction	1985
Date acquired	Apr-14
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 113,343
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 12,928
Unencumbered Apartment Communities [Member] | The Trails of Redmond [Member] | Redmond, WA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	5 years
Unencumbered Apartment Communities [Member] | The Trails of Redmond [Member] | Redmond, WA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Unencumbered Apartment Communities [Member] | Tierra Vista [Member] | Oxnard, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	404
Initial cost [Abstract]
Land				13,652
Buildings and improvements				53,336
Costs capitalized subsequent to acquisition				4,972
Gross amount carried at close of period [Abstract]
Land and improvements				13,661
Buildings and improvements				58,299
Total	$ 71,960			71,960
Accumulated depreciation	$ (27,577)			(27,577)
Date of construction	2001
Date acquired	Jan-01
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 71,960
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 27,577
Unencumbered Apartment Communities [Member] | Tierra Vista [Member] | Oxnard, CA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	3 years
Unencumbered Apartment Communities [Member] | Tierra Vista [Member] | Oxnard, CA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Unencumbered Apartment Communities [Member] | Tiffany Court [Member] | Los Angeles, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	101
Initial cost [Abstract]
Land				6,949
Buildings and improvements				27,796
Costs capitalized subsequent to acquisition				1,541
Gross amount carried at close of period [Abstract]
Land and improvements				6,949
Buildings and improvements				29,337
Total	$ 36,286			36,286
Accumulated depreciation	$ (4,050)			(4,050)
Date of construction	1987
Date acquired	Apr-14
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 36,286
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 4,050
Unencumbered Apartment Communities [Member] | Tiffany Court [Member] | Los Angeles, CA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	5 years
Unencumbered Apartment Communities [Member] | Tiffany Court [Member] | Los Angeles, CA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Unencumbered Apartment Communities [Member] | Trabucco Villas [Member] | Lake Forest, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	132
Initial cost [Abstract]
Land				3,638
Buildings and improvements				8,640
Costs capitalized subsequent to acquisition				2,916
Gross amount carried at close of period [Abstract]
Land and improvements				3,890
Buildings and improvements				11,304
Total	$ 15,194			15,194
Accumulated depreciation	$ (7,610)			(7,610)
Date of construction	1985
Date acquired	Oct-97
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 15,194
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 7,610
Unencumbered Apartment Communities [Member] | Trabucco Villas [Member] | Lake Forest, CA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	3 years
Unencumbered Apartment Communities [Member] | Trabucco Villas [Member] | Lake Forest, CA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Unencumbered Apartment Communities [Member] | Via [Member] | Sunnyvale, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	284
Initial cost [Abstract]
Land				22,000
Buildings and improvements				82,270
Costs capitalized subsequent to acquisition				2,338
Gross amount carried at close of period [Abstract]
Land and improvements				22,016
Buildings and improvements				84,592
Total	$ 106,608			106,608
Accumulated depreciation	$ (21,879)			(21,879)
Date of construction	2011
Date acquired	Jul-11
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 106,608
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 21,879
Unencumbered Apartment Communities [Member] | Via [Member] | Sunnyvale, CA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	3 years
Unencumbered Apartment Communities [Member] | Via [Member] | Sunnyvale, CA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Unencumbered Apartment Communities [Member] | Villa Siena [Member] | Costa Mesa, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	272
Initial cost [Abstract]
Land				13,842
Buildings and improvements				55,367
Costs capitalized subsequent to acquisition				5,382
Gross amount carried at close of period [Abstract]
Land and improvements				13,842
Buildings and improvements				60,749
Total	$ 74,591			74,591
Accumulated depreciation	$ (8,651)			(8,651)
Date of construction	1974
Date acquired	Apr-14
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 74,591
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 8,651
Unencumbered Apartment Communities [Member] | Villa Siena [Member] | Costa Mesa, CA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	5 years
Unencumbered Apartment Communities [Member] | Villa Siena [Member] | Costa Mesa, CA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Unencumbered Apartment Communities [Member] | Village Green [Member] | La Habra, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	272
Initial cost [Abstract]
Land				6,488
Buildings and improvements				36,768
Costs capitalized subsequent to acquisition				3,298
Gross amount carried at close of period [Abstract]
Land and improvements				6,488
Buildings and improvements				40,066
Total	$ 46,554			46,554
Accumulated depreciation	$ (5,852)			(5,852)
Date of construction	1971
Date acquired	Apr-14
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 46,554
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 5,852
Unencumbered Apartment Communities [Member] | Village Green [Member] | La Habra, CA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	5 years
Unencumbered Apartment Communities [Member] | Village Green [Member] | La Habra, CA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Unencumbered Apartment Communities [Member] | Vista Belvedere [Member] | Tiburon, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	76
Initial cost [Abstract]
Land				5,573
Buildings and improvements				11,901
Costs capitalized subsequent to acquisition				8,575
Gross amount carried at close of period [Abstract]
Land and improvements				5,573
Buildings and improvements				20,476
Total	$ 26,049			26,049
Accumulated depreciation	$ (9,931)			(9,931)
Date of construction	1963
Date acquired	Aug-04
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 26,049
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 9,931
Unencumbered Apartment Communities [Member] | Vista Belvedere [Member] | Tiburon, CA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	3 years
Unencumbered Apartment Communities [Member] | Vista Belvedere [Member] | Tiburon, CA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Unencumbered Apartment Communities [Member] | Vox Apartments [Member] | Seattle, WA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	58
Initial cost [Abstract]
Land				5,545
Buildings and improvements				16,635
Costs capitalized subsequent to acquisition				121
Gross amount carried at close of period [Abstract]
Land and improvements				5,545
Buildings and improvements				16,756
Total	$ 22,301			22,301
Accumulated depreciation	$ (2,360)			(2,360)
Date of construction	2013
Date acquired	Oct-13
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 22,301
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 2,360
Unencumbered Apartment Communities [Member] | Vox Apartments [Member] | Seattle, WA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	3 years
Unencumbered Apartment Communities [Member] | Vox Apartments [Member] | Seattle, WA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Unencumbered Apartment Communities [Member] | Walnut Heights [Member] | Walnut, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	163
Initial cost [Abstract]
Land				4,858
Buildings and improvements				19,168
Costs capitalized subsequent to acquisition				4,734
Gross amount carried at close of period [Abstract]
Land and improvements				4,887
Buildings and improvements				23,873
Total	$ 28,760			28,760
Accumulated depreciation	$ (11,505)			(11,505)
Date of construction	1964
Date acquired	Oct-03
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 28,760
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 11,505
Unencumbered Apartment Communities [Member] | Walnut Heights [Member] | Walnut, CA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	3 years
Unencumbered Apartment Communities [Member] | Walnut Heights [Member] | Walnut, CA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Unencumbered Apartment Communities [Member] | Wharfside Pointe [Member] | Seattle, WA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	155
Initial cost [Abstract]
Land				2,245
Buildings and improvements				7,020
Costs capitalized subsequent to acquisition				11,422
Gross amount carried at close of period [Abstract]
Land and improvements				2,258
Buildings and improvements				18,429
Total	$ 20,687			20,687
Accumulated depreciation	$ (12,639)			(12,639)
Date of construction	1990
Date acquired	Jun-94
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 20,687
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 12,639
Unencumbered Apartment Communities [Member] | Wharfside Pointe [Member] | Seattle, WA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	3 years
Unencumbered Apartment Communities [Member] | Wharfside Pointe [Member] | Seattle, WA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Unencumbered Apartment Communities [Member] | Willow Lake [Member] | San Jose, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	508
Initial cost [Abstract]
Land				43,194
Buildings and improvements				101,030
Costs capitalized subsequent to acquisition				12,392
Gross amount carried at close of period [Abstract]
Land and improvements				43,194
Buildings and improvements				113,422
Total	$ 156,616			156,616
Accumulated depreciation	$ (21,870)			(21,870)
Date of construction	1989
Date acquired	Oct-12
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 156,616
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 21,870
Unencumbered Apartment Communities [Member] | Willow Lake [Member] | San Jose, CA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	3 years
Unencumbered Apartment Communities [Member] | Willow Lake [Member] | San Jose, CA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Unencumbered Apartment Communities [Member] | 5600 Wilshire [Member] | Los Angeles, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	284
Initial cost [Abstract]
Land				30,535
Buildings and improvements				91,604
Costs capitalized subsequent to acquisition				1,828
Gross amount carried at close of period [Abstract]
Land and improvements				30,535
Buildings and improvements				93,432
Total	$ 123,967			123,967
Accumulated depreciation	$ (13,001)			(13,001)
Date of construction	2008
Date acquired	Apr-14
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 123,967
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 13,001
Unencumbered Apartment Communities [Member] | 5600 Wilshire [Member] | Los Angeles, CA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	5 years
Unencumbered Apartment Communities [Member] | 5600 Wilshire [Member] | Los Angeles, CA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Unencumbered Apartment Communities [Member] | Wilshire La Brea [Member] | Los Angeles, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	478
Initial cost [Abstract]
Land				56,932
Buildings and improvements				211,998
Costs capitalized subsequent to acquisition				8,806
Gross amount carried at close of period [Abstract]
Land and improvements				56,932
Buildings and improvements				220,804
Total	$ 277,736			277,736
Accumulated depreciation	$ (35,159)			(35,159)
Date of construction	2014
Date acquired	Apr-14
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 277,736
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 35,159
Unencumbered Apartment Communities [Member] | Wilshire La Brea [Member] | Los Angeles, CA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	5 years
Unencumbered Apartment Communities [Member] | Wilshire La Brea [Member] | Los Angeles, CA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Unencumbered Apartment Communities [Member] | Windsor Ridge [Member] | Sunnyvale, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	216
Initial cost [Abstract]
Land				4,017
Buildings and improvements				10,315
Costs capitalized subsequent to acquisition				16,224
Gross amount carried at close of period [Abstract]
Land and improvements				4,021
Buildings and improvements				26,535
Total	$ 30,556			30,556
Accumulated depreciation	$ (19,282)			(19,282)
Date of construction	1989
Date acquired	Mar-89
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 30,556
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 19,282
Unencumbered Apartment Communities [Member] | Windsor Ridge [Member] | Sunnyvale, CA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	3 years
Unencumbered Apartment Communities [Member] | Windsor Ridge [Member] | Sunnyvale, CA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Unencumbered Apartment Communities [Member] | Woodland Commons [Member] | Bellevue, WA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	302
Initial cost [Abstract]
Land				2,040
Buildings and improvements				8,727
Costs capitalized subsequent to acquisition				22,839
Gross amount carried at close of period [Abstract]
Land and improvements				2,044
Buildings and improvements				31,562
Total	$ 33,606			33,606
Accumulated depreciation	$ (18,755)			(18,755)
Date of construction	1978
Date acquired	Mar-90
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 33,606
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 18,755
Unencumbered Apartment Communities [Member] | Woodland Commons [Member] | Bellevue, WA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	3 years
Unencumbered Apartment Communities [Member] | Woodland Commons [Member] | Bellevue, WA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Unencumbered Apartment Communities [Member] | Woodside Village [Member] | Ventura, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Units | apartment	145
Initial cost [Abstract]
Land				5,331
Buildings and improvements				21,036
Costs capitalized subsequent to acquisition				3,974
Gross amount carried at close of period [Abstract]
Land and improvements				5,341
Buildings and improvements				25,000
Total	$ 30,341			30,341
Accumulated depreciation	$ (11,682)			$ (11,682)
Date of construction	1987
Date acquired	Dec-04
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 30,341
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 11,682
Unencumbered Apartment Communities [Member] | Woodside Village [Member] | Ventura, CA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	3 years
Unencumbered Apartment Communities [Member] | Woodside Village [Member] | Ventura, CA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Other Property [Member]
Real Estate and Accumulated Depreciation [Line Items]
Area of real estate property | ft²				106,564
Initial cost [Abstract]
Land				$ 3,079
Buildings and improvements				12,315
Costs capitalized subsequent to acquisition				8,332
Gross amount carried at close of period [Abstract]
Land and improvements				4,308
Buildings and improvements				19,418
Total	$ 23,726			23,726
Accumulated depreciation	(13,252)			$ (13,252)
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	23,726
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	13,252
Other Property [Member] | Derian Office Building [Member] | Irvine, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Area of real estate property | ft²				106,564
Initial cost [Abstract]
Land				$ 3,079
Buildings and improvements				12,315
Costs capitalized subsequent to acquisition				8,332
Gross amount carried at close of period [Abstract]
Land and improvements				4,308
Buildings and improvements				19,418
Total	23,726			23,726
Accumulated depreciation	$ (13,252)			(13,252)
Date of construction	1983
Date acquired	Jul-00
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the end of year	$ 23,726
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the end of year	$ 13,252
Other Property [Member] | Derian Office Building [Member] | Irvine, CA [Member] | Minimum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	3 years
Other Property [Member] | Derian Office Building [Member] | Irvine, CA [Member] | Maximum [Member]
Gross amount carried at close of period [Abstract]
Life Used for Depreciation	30 years
Real Estate, Rental Property [Member]
Gross amount carried at close of period [Abstract]
Total	$ 12,676,306	12,331,469	11,244,681	$ 13,348,831
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at beginning of year	12,676,306	12,331,469	11,244,681
Balance at the end of year	$ 13,348,831	$ 12,676,306	$ 12,331,469