Segment Reporting - Schedule of Reportable Operating Segments of Revenue and NOI (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Revenues from External Customers and Long-Lived Assets [Line Items]
Rental and other property	$ 1,877,964	$ 1,764,185	$ 1,658,264
Property operating expenses, including real estate taxes	558,986	521,536	487,758
Net operating income	1,318,978	1,242,649	1,170,506
Management and other fees from affiliates	9,381	10,265	11,131
Corporate-level property management expenses	(49,052)	(46,208)	(43,593)
Depreciation and amortization	(607,542)	(580,220)	(548,438)
General and administrative	(71,948)	(98,902)	(63,474)
Expensed acquisition and investment related costs	(25)	(72)	(595)
Casualty loss	0	0	(433)
Gain on sale of real estate and land	299,524	175,583	59,238
Interest expense	(258,404)	(235,529)	(212,905)
Total return swap income	4,729	3,099	3,148
Interest and other income	20,004	80,951	46,259
Equity income from co-investments	35,464	48,206	10,561
Tax benefit (expense) on unconsolidated co-investments	2,096	929	(697)
Loss on early retirement of debt	(762)	0	0
Gain on remeasurement of co-investment	330	210,555	0
Net income	702,773	811,306	430,708
Operating segments | Southern California
Revenues from External Customers and Long-Lived Assets [Line Items]
Rental and other property	763,124	714,975	654,422
Property operating expenses, including real estate taxes	225,015	208,380	190,897
Net operating income	538,109	506,595	463,525
Operating segments | Northern California
Revenues from External Customers and Long-Lived Assets [Line Items]
Rental and other property	760,821	663,825	628,880
Property operating expenses, including real estate taxes	235,979	202,059	188,041
Net operating income	524,842	461,766	440,839
Operating segments | Seattle Metro
Revenues from External Customers and Long-Lived Assets [Line Items]
Rental and other property	313,410	295,002	282,092
Property operating expenses, including real estate taxes	90,967	87,558	81,334
Net operating income	222,443	207,444	200,758
Other real estate assets
Revenues from External Customers and Long-Lived Assets [Line Items]
Rental and other property	40,609	90,383	92,870
Property operating expenses, including real estate taxes	7,025	23,539	27,486
Net operating income	$ 33,584	$ 66,844	$ 65,384