Real Estate Summary of Real Estate Investments (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Real Estate Properties [Line Items]
Construction in progress	$ 91,047	$ 91,264
Total Real estate, at cost	3,246,874	3,188,697
Accumulated depreciation	(754,140)	(665,222)
Net real estate	2,492,734	2,523,475
Total Retail
Real Estate Properties [Line Items]
Net real estate	607,918	624,912
Total Office
Real Estate Properties [Line Items]
Net real estate	1,317,107	1,317,854
Total Multifamily
Real Estate Properties [Line Items]
Net real estate	389,804	401,152
Total Mixed-Use
Real Estate Properties [Line Items]
Net real estate	177,905	179,557
Real Estate Investment
Real Estate Properties [Line Items]
Land	628,557	628,557
Buildings	2,184,934	2,173,740
Land improvements	69,049	67,144
Tenant improvements	276,639	241,621
Furniture, fixtures, and equipment	36,436	26,158
Construction in progress	51,259	51,477
Total Real estate, at cost	3,246,874	3,188,697
Accumulated depreciation	(754,140)	(665,222)
Net real estate	2,492,734	2,523,475
Real Estate Investment \| Total Retail
Real Estate Properties [Line Items]
Land	254,016	254,016
Buildings	526,522	523,645
Land improvements	47,425	46,335
Tenant improvements	88,326	87,707
Furniture, fixtures, and equipment	1,069	911
Construction in progress	5,170	6,487
Total Real estate, at cost	922,528	919,101
Accumulated depreciation	(314,610)	(294,189)
Net real estate	607,918	624,912
Real Estate Investment \| Total Office
Real Estate Properties [Line Items]
Land	225,238	225,238
Buildings	1,137,711	1,132,990
Land improvements	11,672	11,097
Tenant improvements	186,423	151,662
Furniture, fixtures, and equipment	3,236	3,065
Construction in progress	43,595	35,397
Total Real estate, at cost	1,607,875	1,559,449
Accumulated depreciation	(290,768)	(241,595)
Net real estate	1,317,107	1,317,854
Real Estate Investment \| Total Multifamily
Real Estate Properties [Line Items]
Land	72,668	72,668
Buildings	392,224	390,379
Land improvements	7,346	7,106
Tenant improvements	0	0
Furniture, fixtures, and equipment	16,480	14,995
Construction in progress	1,831	2,212
Total Real estate, at cost	490,549	487,360
Accumulated depreciation	(100,745)	(86,208)
Net real estate	389,804	401,152
Real Estate Investment \| Total Mixed-Use
Real Estate Properties [Line Items]
Land	76,635	76,635
Buildings	128,477	126,726
Land improvements	2,606	2,606
Tenant improvements	1,890	2,252
Furniture, fixtures, and equipment	15,651	7,187
Construction in progress	663	7,381
Total Real estate, at cost	225,922	222,787
Accumulated depreciation	(48,017)	(43,230)
Net real estate	$ 177,905	$ 179,557

Amount before accumulated depreciation of building structures held for productive use including addition, improvement, or renovation to the structure, including, but not limited to, interior masonry, interior flooring, electrical, and plumbing.

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Amount before accumulated deprecation and depletion of additions or improvements to real estate held for productive use. Examples include, but are not limited to, walkways, driveways, fences, and parking lots.

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Carrying amount as of the balance sheet date of improvements having a life longer than one year that were made for the benefit of one or more tenants.

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