Segment Reporting - Reportable Operating Segments of Revenue and NOI (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Revenues from External Customers and Long-Lived Assets [Line Items]
Rental and other property	$ 1,764,185	$ 1,658,264	$ 1,595,675
Property operating expenses, including real estate taxes	519,526	485,479	467,269
Total net operating income	1,244,659	1,172,785	1,128,406
Management and other fees from affiliates	10,265	11,131	11,139
Corporate-level property management expenses	(48,218)	(45,872)	(40,704)
Depreciation and amortization	(580,220)	(548,438)	(539,319)
General and administrative	(98,902)	(63,474)	(56,577)
Expensed acquisition and investment related costs	(72)	(595)	(2,132)
Casualty loss	0	(433)	0
Gain on sale of real estate and land	175,583	59,238	94,416
Interest expense	(235,529)	(212,905)	(204,798)
Total return swap income	3,099	3,148	7,907
Interest and other income (loss)	80,951	46,259	(19,040)
Equity income from co-investments	48,206	10,561	26,030
Tax benefit (expense) on unconsolidated co-investments	929	(697)	10,236
Loss on early retirement of debt, net	0	0	(2)
Gain on remeasurement of co-investments	210,555	0	17,423
Net income	811,306	430,708	432,985
Operating segments | Southern California
Revenues from External Customers and Long-Lived Assets [Line Items]
Rental and other property	744,004	682,116	646,252
Property operating expenses, including real estate taxes	216,355	199,103	186,490
Total net operating income	527,649	483,013	459,762
Operating segments | Northern California
Revenues from External Customers and Long-Lived Assets [Line Items]
Rental and other property	677,393	642,658	615,677
Property operating expenses, including real estate taxes	207,484	193,161	185,403
Total net operating income	469,909	449,497	430,274
Operating segments | Seattle Metro
Revenues from External Customers and Long-Lived Assets [Line Items]
Rental and other property	295,002	282,092	271,248
Property operating expenses, including real estate taxes	87,144	80,864	80,018
Total net operating income	207,858	201,228	191,230
Other real estate assets
Revenues from External Customers and Long-Lived Assets [Line Items]
Rental and other property	47,786	51,398	62,498
Property operating expenses, including real estate taxes	8,543	12,351	15,358
Total net operating income	$ 39,243	$ 39,047	$ 47,140