Segment Information (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2022 USD ($) segment	Mar. 31, 2021 USD ($)	Dec. 31, 2021 USD ($)	Dec. 31, 2020 USD ($)
Revenues from External Customers and Long-Lived Assets [Line Items]
Number of reportable segments | segment	3
Number of operating segments | segment	3
Net operating income	$ 263,116	$ 242,463
Corporate-level property management expenses	(10,172)	(9,013)
Depreciation and amortization	(133,533)	(128,587)
General and administrative	(12,242)	(9,812)
Expensed acquisition and investment related costs	(8)	(15)
Gain on sale of real estate and land	0	100,096
Interest expense	(50,377)	(51,649)
Total return swap income	2,544	2,844
Interest and other (loss) income	(7,567)	14,387
Equity income from co-investments	21,171	17,011
Deferred tax benefit (expense) on unconsolidated co-investments	2,754	(508)
Loss on early retirement of debt, net	0	(2,517)
Net income (loss)	78,375	176,949
Net reportable operating segment - real estate assets	10,904,520		$ 10,983,073
Real estate under development	112,815		111,562
Co-investments	1,144,542		1,177,802
Cash and cash equivalents, including restricted cash	108,553	113,360	58,638	$ 84,041
Marketable securities	169,702		191,829
Notes and other receivables	205,420		341,033
Operating lease right-of-use assets	68,158		68,972
Prepaid expenses and other assets	56,591		64,964
Total assets	12,770,301		12,997,873
Rental and Other Property Revenues
Revenues from External Customers and Long-Lived Assets [Line Items]
Total revenues	379,216	352,876
Management and Other Fees From Affiliates Income
Revenues from External Customers and Long-Lived Assets [Line Items]
Total revenues	2,689	2,249
Operating Segments | Southern California
Revenues from External Customers and Long-Lived Assets [Line Items]
Net operating income	110,213	98,577
Net reportable operating segment - real estate assets	3,981,059		4,018,839
Operating Segments | Southern California | Rental and Other Property Revenues
Revenues from External Customers and Long-Lived Assets [Line Items]
Total revenues	156,969	141,969
Operating Segments | Northern California
Revenues from External Customers and Long-Lived Assets [Line Items]
Net operating income	104,985	101,649
Net reportable operating segment - real estate assets	5,425,077		5,460,701
Operating Segments | Northern California | Rental and Other Property Revenues
Revenues from External Customers and Long-Lived Assets [Line Items]
Total revenues	152,590	146,690
Operating Segments | Seattle Metro
Revenues from External Customers and Long-Lived Assets [Line Items]
Net operating income	43,296	38,792
Net reportable operating segment - real estate assets	1,397,195		1,407,033
Operating Segments | Seattle Metro | Rental and Other Property Revenues
Revenues from External Customers and Long-Lived Assets [Line Items]
Total revenues	64,203	58,633
Other real estate assets
Revenues from External Customers and Long-Lived Assets [Line Items]
Net operating income	4,622	3,445
Net reportable operating segment - real estate assets	101,189		$ 96,500
Other real estate assets | Rental and Other Property Revenues
Revenues from External Customers and Long-Lived Assets [Line Items]
Total revenues	$ 5,454	$ 5,584