Revenues - Schedule of Disaggregation of Revenue (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2025 USD ($) community	Dec. 31, 2024 USD ($) property	Dec. 31, 2023 USD ($)
Disaggregation of Revenue [Line Items]
Total rental and other property revenues	$ 1,877,964	$ 1,764,185	$ 1,658,264
Management and other fees from affiliates	9,381	10,265	11,131
Total revenues	$ 1,887,345	$ 1,774,450	1,669,395
Apartment communities owned (in communities)	259	13
Operating segments | Southern California
Disaggregation of Revenue [Line Items]
Total rental and other property revenues	$ 763,124	$ 714,975	654,422
Operating segments | Northern California
Disaggregation of Revenue [Line Items]
Total rental and other property revenues	760,821	663,825	628,880
Operating segments | Seattle Metro
Disaggregation of Revenue [Line Items]
Total rental and other property revenues	313,410	295,002	282,092
Other real estate assets
Disaggregation of Revenue [Line Items]
Total rental and other property revenues	40,609	90,383	92,870
Rental income
Disaggregation of Revenue [Line Items]
Total rental and other property revenues	1,850,551	1,735,411	1,636,070
Other property
Disaggregation of Revenue [Line Items]
Total rental and other property revenues	27,413	28,774	22,194
Total rental and other property revenues
Disaggregation of Revenue [Line Items]
Total rental and other property revenues	1,877,964	1,764,185	1,658,264
Total rental and other property revenues | Same-property
Disaggregation of Revenue [Line Items]
Total rental and other property revenues	$ 1,642,989	1,590,404	1,540,045
Occupancy threshold for classification as stabilized	90.00%
Total rental and other property revenues | Acquisitions
Disaggregation of Revenue [Line Items]
Total rental and other property revenues	$ 169,002	58,158	1,037
Total rental and other property revenues | Non-residential/other, net
Disaggregation of Revenue [Line Items]
Total rental and other property revenues	$ 64,952	115,644	119,725
Apartment communities owned (in communities) | community	2
Total rental and other property revenues | Straight line rent concession
Disaggregation of Revenue [Line Items]
Straight line rent concession	$ 1,021	(21)	(2,543)
Total rental and other property revenues | Operating segments | Southern California
Disaggregation of Revenue [Line Items]
Total rental and other property revenues	763,124	714,975	654,422
Total rental and other property revenues | Operating segments | Northern California
Disaggregation of Revenue [Line Items]
Total rental and other property revenues	760,821	663,825	628,880
Total rental and other property revenues | Operating segments | Seattle Metro
Disaggregation of Revenue [Line Items]
Total rental and other property revenues	313,410	295,002	282,092
Total rental and other property revenues | Other real estate assets
Disaggregation of Revenue [Line Items]
Total rental and other property revenues	$ 40,609	$ 90,383	$ 92,870