Reportable Segments - NOI from Our Rental Real Estate for Each Segment Specific to Continuing Operations (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Segment Reporting Information [Line Items]
Rental income	$ 2,735,180	$ 2,463,997	$ 2,571,705
Operating income	1,116,046	1,675,841	1,317,990
Total Assets	20,218,262	21,169,241
Same Store
Segment Reporting Information [Line Items]
Rental income	2,533,577	2,291,604	2,425,025
Operating expenses	802,291	774,504	780,381
Operating income	1,731,286	1,517,100	1,644,644
Total Assets	16,919,631	17,457,178
Capital Expenditures	195,110	143,634
Non-same store/other
Segment Reporting Information [Line Items]
Rental income	201,603	172,393	146,680
Operating expenses	69,986	76,133	42,179
Operating income	131,617	96,260	104,501
Total Assets	3,298,631	3,712,063
Capital Expenditures	25,976	7,385
Same Store, Non-same Store and Other
Segment Reporting Information [Line Items]
Rental income	2,735,180	2,463,997	2,571,705
Operating expenses	872,277	850,637	822,560
Operating income	1,862,903	1,613,360	1,749,145
Total Assets	20,218,262	21,169,241
Capital Expenditures	221,086	151,019
Los Angeles | Same Store
Segment Reporting Information [Line Items]
Rental income	469,180	431,954	444,129
Operating expenses	137,078	132,274	140,469
Operating income	332,102	299,680	303,660
Total Assets	2,590,661	2,668,136
Capital Expenditures	35,481	20,917
Orange County | Same Store
Segment Reporting Information [Line Items]
Rental income	122,660	109,427	105,236
Operating expenses	26,338	24,986	24,545
Operating income	96,322	84,441	80,691
Total Assets	356,396	371,063
Capital Expenditures	7,885	5,647
San Diego | Same Store
Segment Reporting Information [Line Items]
Rental income	86,728	78,709	74,737
Operating expenses	19,395	18,395	18,176
Operating income	67,333	60,314	56,561
Total Assets	228,471	232,345
Capital Expenditures	8,798	2,899
Subtotal - Southern California | Same Store
Segment Reporting Information [Line Items]
Rental income	678,568	620,090	624,102
Operating expenses	182,811	175,655	183,190
Operating income	495,757	444,435	440,912
Total Assets	3,175,528	3,271,544
Capital Expenditures	52,164	29,463
San Francisco | Same Store
Segment Reporting Information [Line Items]
Rental income	418,941	383,817	435,371
Operating expenses	124,952	118,795	117,085
Operating income	293,989	265,022	318,286
Total Assets	3,068,951	3,165,347
Capital Expenditures	33,854	20,021
Washington D.C. | Same Store
Segment Reporting Information [Line Items]
Rental income	411,975	389,205	405,571
Operating expenses	136,130	129,065	125,353
Operating income	275,845	260,140	280,218
Total Assets	3,027,549	3,134,677
Capital Expenditures	34,174	27,061
New York | Same Store
Segment Reporting Information [Line Items]
Rental income	434,820	367,370	424,534
Operating expenses	186,896	182,631	197,740
Operating income	247,924	184,739	226,794
Total Assets	3,421,373	3,513,047
Capital Expenditures	21,636	28,742
Seattle | Same Store
Segment Reporting Information [Line Items]
Rental income	282,902	256,988	257,372
Operating expenses	79,101	80,775	74,362
Operating income	203,801	176,213	183,010
Total Assets	2,076,320	2,140,925
Capital Expenditures	28,086	15,203
Boston | Same Store
Segment Reporting Information [Line Items]
Rental income	262,604	235,050	240,158
Operating expenses	79,979	76,374	71,611
Operating income	182,625	158,676	168,547
Total Assets	1,676,783	1,739,184
Capital Expenditures	23,057	21,129
Denver | Same Store
Segment Reporting Information [Line Items]
Rental income	43,767	39,084	37,917
Operating expenses	12,422	11,209	11,040
Operating income	31,345	27,875	26,877
Total Assets	473,127	492,454
Capital Expenditures	2,139	2,015
Non-same store | Non-same store/other
Segment Reporting Information [Line Items]
Rental income	179,707	59,629	11,791
Operating expenses	70,654	27,691	2,706
Operating income	109,053	31,938	9,085
Total Assets	2,501,008	2,439,634
Capital Expenditures	25,429	4,491
Other | Non-same store/other
Segment Reporting Information [Line Items]
Rental income	21,896	112,764	134,889
Operating expenses	(668)	48,442	39,473
Operating income	22,564	64,322	$ 95,416
Total Assets	797,623	1,272,429
Capital Expenditures	$ 547	$ 2,894