Segment Reporting - Segment Information (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Segment Reporting
Total revenue	$ 697,635	$ 665,288	$ 2,063,204	$ 1,923,775
NOI	472,377	442,997	1,401,416	1,282,335
Gross real estate	26,467,496	25,245,314	26,467,496	25,245,314
Gross real estate assets held for sale	63,754		63,754
Operating Segments | Same Store
Segment Reporting
Total revenue	642,093	611,788	1,899,041	1,778,308
NOI	438,267	417,755	1,308,404	1,225,086
Gross real estate	22,341,497	22,139,558	22,341,497	22,139,558
Operating Segments | Same Store | New England
Segment Reporting
Total revenue	92,967	88,399	273,699	252,814
NOI	61,146	58,953	182,121	167,090
Gross real estate	2,915,561	2,886,605	2,915,561	2,886,605
Operating Segments | Same Store | Metro NY/NJ
Segment Reporting
Total revenue	133,727	127,713	395,319	365,811
NOI	90,056	86,387	270,617	250,687
Gross real estate	4,422,604	4,392,552	4,422,604	4,392,552
Operating Segments | Same Store | Mid-Atlantic
Segment Reporting
Total revenue	93,507	88,964	275,873	258,952
NOI	63,573	59,554	190,587	176,267
Gross real estate	3,429,203	3,389,133	3,429,203	3,389,133
Operating Segments | Same Store | Southeast Florida
Segment Reporting
Total revenue	18,789	17,798	56,908	51,292
NOI	12,260	11,683	37,535	32,964
Gross real estate	801,062	796,120	801,062	796,120
Operating Segments | Same Store | Denver, CO
Segment Reporting
Total revenue	7,167	6,891	21,049	19,869
NOI	5,061	4,905	14,827	14,531
Gross real estate	322,024	321,354	322,024	321,354
Operating Segments | Same Store | Pacific Northwest
Segment Reporting
Total revenue	42,969	42,628	128,758	122,668
NOI	29,998	30,077	91,028	87,147
Gross real estate	1,542,199	1,531,682	1,542,199	1,531,682
Operating Segments | Same Store | Northern California
Segment Reporting
Total revenue	106,728	103,374	318,833	301,367
NOI	75,921	73,607	227,387	214,527
Gross real estate	3,781,910	3,752,632	3,781,910	3,752,632
Operating Segments | Same Store | Southern California
Segment Reporting
Total revenue	140,117	130,453	410,657	389,341
NOI	96,248	88,886	282,195	270,804
Gross real estate	4,799,299	4,746,147	4,799,299	4,746,147
Operating Segments | Same Store | Other Expansion Regions
Segment Reporting
Total revenue	6,122	5,568	17,945	16,194
NOI	4,004	3,703	12,107	11,069
Gross real estate	327,635	323,333	327,635	323,333
Operating Segments | Other Stabilized
Segment Reporting
Total revenue	33,241	28,146	97,210	62,479
NOI	23,437	20,515	68,104	44,622
Gross real estate	1,608,094	1,435,965	1,608,094	1,435,965
Operating Segments | Development / Redevelopment
Segment Reporting
Total revenue	17,309	7,713	40,839	20,271
NOI	10,673	4,727	24,908	12,627
Gross real estate	2,204,049	1,386,757	2,204,049	1,386,757
Operating Segments | Disposals
Segment Reporting
Gross real estate		280,529		280,529
Land Held for Future Development
Segment Reporting
Gross real estate	183,158	167,277	183,158	167,277
Non-allocated
Segment Reporting
Total revenue	1,934	1,399	5,712	3,054
Gross real estate	130,698	115,757	130,698	115,757
Continuing Operations
Segment Reporting
Total revenue	694,577	649,046	2,042,802	1,864,112
Continuing Operations | Operating Segments | Same Store
Segment Reporting
Total revenue	642,093	611,788	1,899,041	1,778,308
Continuing Operations | Operating Segments | Other Stabilized
Segment Reporting
Total revenue	33,241	28,146	97,210	62,479
Continuing Operations | Non-allocated
Segment Reporting
Total revenue	$ 1,934	$ 1,399	$ 5,712	$ 3,054