Schedule III-REAL ESTATE AND ACCUMULATE DEPRECIATION (Details) (USD $)	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
SCHEDULE III - REAL ESTATE AND ACCUMULATED DEPRECIATION
Encumbrances	$ 221,847,000
Initial Cost
Land	354,035,000
Bldg. & Improve.	1,597,138,000
Net Improvements (Write-Offs) Since Acquisition	85,621,000
Gross Amount at Which Carried
Land	354,035,000
Building and Improvements	1,682,759,000
Total	2,036,794,000	1,953,848,000
Accumulated Depreciation	320,857,000	271,683,000	231,080,000	184,626,000
Other disclosures
Federal tax cost basis	2,100,000,000
Office | 7083 Hollywood Blvd Los Angeles, CA
Initial Cost
Land	6,276,000
Bldg. & Improve.	13,161,000
Net Improvements (Write-Offs) Since Acquisition	3,146,000
Gross Amount at Which Carried
Land	6,276,000
Building and Improvements	16,307,000
Total	22,583,000
Accumulated Depreciation	4,271,000
Office | 800 N Capitol Street Washington, DC
Initial Cost
Bldg. & Improve.	109,948,000
Net Improvements (Write-Offs) Since Acquisition	(8,512,000)
Gross Amount at Which Carried
Building and Improvements	101,436,000
Total	101,436,000
Accumulated Depreciation	23,037,000
Office | 370 L'Enfant Prom Washington, DC
SCHEDULE III - REAL ESTATE AND ACCUMULATED DEPRECIATION
Encumbrances	26,783,000
Initial Cost
Land	33,936,000
Bldg. & Improve.	145,796,000
Net Improvements (Write-Offs) Since Acquisition	(6,450,000)
Gross Amount at Which Carried
Land	33,936,000
Building and Improvements	139,346,000
Total	173,282,000
Accumulated Depreciation	32,181,000
Office | 260 Townsend San Francisco, CA
Initial Cost
Land	7,574,000
Bldg. & Improve.	13,843,000
Net Improvements (Write-Offs) Since Acquisition	724,000
Gross Amount at Which Carried
Land	7,574,000
Building and Improvements	14,567,000
Total	22,141,000
Accumulated Depreciation	5,651,000
Office | 830 1st Street Washington, DC
SCHEDULE III - REAL ESTATE AND ACCUMULATED DEPRECIATION
Encumbrances	46,000,000
Initial Cost
Land	18,095,000
Bldg. & Improve.	62,017,000
Net Improvements (Write-Offs) Since Acquisition	(1,398,000)
Gross Amount at Which Carried
Land	18,095,000
Building and Improvements	60,619,000
Total	78,714,000
Accumulated Depreciation	12,450,000
Office | BB&T Center Charlotte, NC
Initial Cost
Land	7,702,000
Bldg. & Improve.	109,006,000
Net Improvements (Write-Offs) Since Acquisition	5,627,000
Gross Amount at Which Carried
Land	7,702,000
Building and Improvements	114,633,000
Total	122,335,000
Accumulated Depreciation	28,139,000
Office | Civic Center Santa Ana, CA
Initial Cost
Land	1,354,000
Bldg. & Improve.	5,496,000
Net Improvements (Write-Offs) Since Acquisition	1,467,000
Gross Amount at Which Carried
Land	1,354,000
Building and Improvements	6,963,000
Total	8,317,000
Accumulated Depreciation	2,255,000
Office | Penn Field Austin, TX
SCHEDULE III - REAL ESTATE AND ACCUMULATED DEPRECIATION
Encumbrances	12,442,000
Initial Cost
Land	9,569,000
Bldg. & Improve.	18,593,000
Net Improvements (Write-Offs) Since Acquisition	2,774,000
Gross Amount at Which Carried
Land	9,569,000
Building and Improvements	21,367,000
Total	30,936,000
Accumulated Depreciation	5,598,000
Office | 899 N Capitol Street Washington, DC
Initial Cost
Land	34,641,000
Bldg. & Improve.	84,466,000
Net Improvements (Write-Offs) Since Acquisition	9,762,000
Gross Amount at Which Carried
Land	34,641,000
Building and Improvements	94,228,000
Total	128,869,000
Accumulated Depreciation	18,947,000
Office | 999 N Capitol Street Washington, DC
Initial Cost
Land	32,221,000
Bldg. & Improve.	86,526,000
Net Improvements (Write-Offs) Since Acquisition	9,868,000
Gross Amount at Which Carried
Land	32,221,000
Building and Improvements	96,394,000
Total	128,615,000
Accumulated Depreciation	19,383,000
Office | 901 N Capitol Street Washington, DC
Initial Cost
Land	27,117,000
Gross Amount at Which Carried
Land	27,117,000
Total	27,117,000
Office | 1333 Broadway Oakland, CA
Initial Cost
Land	7,048,000
Bldg. & Improve.	41,578,000
Net Improvements (Write-Offs) Since Acquisition	5,985,000
Gross Amount at Which Carried
Land	7,048,000
Building and Improvements	47,563,000
Total	54,611,000
Accumulated Depreciation	7,572,000
Office | 1901 Harrison Street Oakland, CA
Initial Cost
Land	3,838,000
Bldg. & Improve.	68,106,000
Net Improvements (Write-Offs) Since Acquisition	5,239,000
Gross Amount at Which Carried
Land	3,838,000
Building and Improvements	73,345,000
Total	77,183,000
Accumulated Depreciation	14,426,000
Office | 2100 Franklin Street Oakland, CA
Initial Cost
Land	4,277,000
Bldg. & Improve.	34,033,000
Net Improvements (Write-Offs) Since Acquisition	12,698,000
Gross Amount at Which Carried
Land	4,277,000
Building and Improvements	46,731,000
Total	51,008,000
Accumulated Depreciation	10,086,000
Office | 2101 Webster Street Oakland, CA
Initial Cost
Land	4,752,000
Bldg. & Improve.	109,812,000
Net Improvements (Write-Offs) Since Acquisition	18,965,000
Gross Amount at Which Carried
Land	4,752,000
Building and Improvements	128,777,000
Total	133,529,000
Accumulated Depreciation	26,004,000
Office | 2353 Webster Street Parking Garage Oakland, CA
Initial Cost
Bldg. & Improve.	9,138,000
Net Improvements (Write-Offs) Since Acquisition	51,000
Gross Amount at Which Carried
Building and Improvements	9,189,000
Total	9,189,000
Accumulated Depreciation	1,446,000
Office | 1 Kaiser Plaza Oakland, CA
Initial Cost
Land	9,261,000
Bldg. & Improve.	113,619,000
Net Improvements (Write-Offs) Since Acquisition	8,924,000
Gross Amount at Which Carried
Land	9,261,000
Building and Improvements	122,543,000
Total	131,804,000
Accumulated Depreciation	23,933,000
Office | 980 9th Street Sacramento, CA
Initial Cost
Land	3,380,000
Bldg. & Improve.	86,939,000
Net Improvements (Write-Offs) Since Acquisition	4,550,000
Gross Amount at Which Carried
Land	3,380,000
Building and Improvements	91,489,000
Total	94,869,000
Accumulated Depreciation	15,584,000
Office | 1010 8th Street Parking Garage & Retail Sacramento, CA
Initial Cost
Land	1,020,000
Bldg. & Improve.	1,980,000
Net Improvements (Write-Offs) Since Acquisition	96,000
Gross Amount at Which Carried
Land	1,020,000
Building and Improvements	2,076,000
Total	3,096,000
Accumulated Depreciation	354,000
Office | 211 Main Street San Francisco, CA
SCHEDULE III - REAL ESTATE AND ACCUMULATED DEPRECIATION
Encumbrances	32,070,000
Initial Cost
Land	14,364,000
Bldg. & Improve.	106,875,000
Net Improvements (Write-Offs) Since Acquisition	1,479,000
Gross Amount at Which Carried
Land	14,364,000
Building and Improvements	108,354,000
Total	122,718,000
Accumulated Depreciation	20,808,000
Office | 11600 Wilshire Blvd Los Angeles, CA
Initial Cost
Land	3,477,000
Bldg. & Improve.	18,522,000
Net Improvements (Write-Offs) Since Acquisition	1,113,000
Gross Amount at Which Carried
Land	3,477,000
Building and Improvements	19,635,000
Total	23,112,000
Accumulated Depreciation	2,456,000
Office | 11620 Wilshire Blvd Los Angeles, CA
SCHEDULE III - REAL ESTATE AND ACCUMULATED DEPRECIATION
Encumbrances	33,734,000
Initial Cost
Land	7,672,000
Bldg. & Improve.	51,999,000
Net Improvements (Write-Offs) Since Acquisition	5,122,000
Gross Amount at Which Carried
Land	7,672,000
Building and Improvements	57,121,000
Total	64,793,000
Accumulated Depreciation	6,902,000
Office | 4750 Wilshire Blvd Los Angeles, CA
Initial Cost
Land	16,633,000
Bldg. & Improve.	28,985,000
Net Improvements (Write-Offs) Since Acquisition	59,000
Gross Amount at Which Carried
Land	16,633,000
Building and Improvements	29,044,000
Total	45,677,000
Accumulated Depreciation	610,000
Office | Lindblade Media Center Los Angeles, CA
Initial Cost
Land	6,342,000
Bldg. & Improve.	11,568,000
Gross Amount at Which Carried
Land	6,342,000
Building and Improvements	11,568,000
Total	17,910,000
Accumulated Depreciation	75,000
Multifamily | 3636 McKinney Avenue Dallas, TX
SCHEDULE III - REAL ESTATE AND ACCUMULATED DEPRECIATION
Encumbrances	9,696,000
Initial Cost
Land	3,806,000
Bldg. & Improve.	11,077,000
Net Improvements (Write-Offs) Since Acquisition	357,000
Gross Amount at Which Carried
Land	3,806,000
Building and Improvements	11,434,000
Total	15,240,000
Accumulated Depreciation	1,554,000
Multifamily | 3839 McKinney Avenue Dallas, TX
SCHEDULE III - REAL ESTATE AND ACCUMULATED DEPRECIATION
Encumbrances	6,432,000
Initial Cost
Land	1,679,000
Bldg. & Improve.	8,621,000
Net Improvements (Write-Offs) Since Acquisition	311,000
Gross Amount at Which Carried
Land	1,679,000
Building and Improvements	8,932,000
Total	10,611,000
Accumulated Depreciation	1,218,000
Multifamily | 4649 Cole Avenue Dallas, TX
SCHEDULE III - REAL ESTATE AND ACCUMULATED DEPRECIATION
Encumbrances	24,398,000
Initial Cost
Land	17,483,000
Bldg. & Improve.	16,355,000
Net Improvements (Write-Offs) Since Acquisition	4,806,000
Gross Amount at Which Carried
Land	17,483,000
Building and Improvements	21,161,000
Total	38,644,000
Accumulated Depreciation	2,907,000
Multifamily | Memorial Hills Houston, TX
SCHEDULE III - REAL ESTATE AND ACCUMULATED DEPRECIATION
Encumbrances	30,292,000
Initial Cost
Land	9,811,000
Bldg. & Improve.	40,150,000
Net Improvements (Write-Offs) Since Acquisition	506,000
Gross Amount at Which Carried
Land	9,811,000
Building and Improvements	40,656,000
Total	50,467,000
Accumulated Depreciation	5,589,000
Multifamily | 47 E 34th Street New York, NY
Initial Cost
Land	30,612,000
Bldg. & Improve.	31,145,000
Net Improvements (Write-Offs) Since Acquisition	312,000
Gross Amount at Which Carried
Land	30,612,000
Building and Improvements	31,457,000
Total	62,069,000
Accumulated Depreciation	2,523,000
Hotel | Courtyard Oakland Oakland, CA
Initial Cost
Land	4,384,000
Bldg. & Improve.	16,168,000
Net Improvements (Write-Offs) Since Acquisition	1,170,000
Gross Amount at Which Carried
Land	4,384,000
Building and Improvements	17,338,000
Total	21,722,000
Accumulated Depreciation	3,519,000
Hotel | Sheraton Grand Hotel Sacramento, CA
Initial Cost
Land	3,497,000
Bldg. & Improve.	107,447,000
Net Improvements (Write-Offs) Since Acquisition	(3,749,000)
Gross Amount at Which Carried
Land	3,497,000
Building and Improvements	103,698,000
Total	107,195,000
Accumulated Depreciation	18,175,000
Hotel | Sheraton Grand Hotel Parking & Retail Sacramento, CA
Initial Cost
Land	6,552,000
Bldg. & Improve.	10,996,000
Net Improvements (Write-Offs) Since Acquisition	(41,000)
Gross Amount at Which Carried
Land	6,552,000
Building and Improvements	10,955,000
Total	17,507,000
Accumulated Depreciation	1,920,000
Hotel | Los Angeles, CA
Initial Cost
Land	15,662,000
Bldg. & Improve.	23,173,000
Net Improvements (Write-Offs) Since Acquisition	660,000
Gross Amount at Which Carried
Land	15,662,000
Building and Improvements	23,833,000
Total	39,495,000
Accumulated Depreciation	$ 1,284,000