Segment Reporting - Segment Information (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Segment Reporting
Total revenue	$ 613,927	$ 551,135
NOI	418,291	354,898
Gross real estate	25,135,184	23,574,372
Operating Segments | Same Store
Segment Reporting
Total revenue	546,839	503,193
NOI	376,427	340,455
Gross real estate	20,459,052	20,287,339
Operating Segments | Same Store | New England
Segment Reporting
Total revenue	81,818	74,871
NOI	52,587	47,445
Gross real estate	2,888,176	2,862,749
Operating Segments | Same Store | Metro NY/NJ
Segment Reporting
Total revenue	115,476	106,846
NOI	79,506	73,273
Gross real estate	4,244,572	4,215,804
Operating Segments | Same Store | Mid-Atlantic
Segment Reporting
Total revenue	82,093	78,105
NOI	55,992	53,051
Gross real estate	3,257,920	3,233,446
Operating Segments | Same Store | Southeast Florida
Segment Reporting
Total revenue	9,071	7,241
NOI	5,977	4,189
Gross real estate	396,555	394,451
Operating Segments | Same Store | Denver, CO
Segment Reporting
Total revenue	6,315	5,652
NOI	4,727	4,019
Gross real estate	320,803	319,667
Operating Segments | Same Store | Pacific Northwest
Segment Reporting
Total revenue	34,298	30,532
NOI	24,222	20,391
Gross real estate	1,290,332	1,283,372
Operating Segments | Same Store | Northern California
Segment Reporting
Total revenue	96,729	92,855
NOI	68,699	65,552
Gross real estate	3,651,325	3,614,708
Operating Segments | Same Store | Southern California
Segment Reporting
Total revenue	121,039	107,091
NOI	84,717	72,535
Gross real estate	4,409,369	4,363,142
Operating Segments | Other Stabilized
Segment Reporting
Total revenue	45,599	20,958
NOI	29,542	10,971
Gross real estate	2,511,859	1,665,418
Operating Segments | Development / Redevelopment
Segment Reporting
Total revenue	17,518	7,073
NOI	12,322	3,472
Gross real estate	1,721,164	1,081,493
Operating Segments | Disposals
Segment Reporting
Gross real estate		485,631
Land Held for Future Development
Segment Reporting
Gross real estate	218,852	184,058
Non-allocated
Segment Reporting
Total revenue	752	877
Gross real estate	224,257	356,064
Continuing Operations
Segment Reporting
Total revenue	610,708	532,101
Continuing Operations | Operating Segments | Same Store
Segment Reporting
Total revenue	546,839	503,193
Continuing Operations | Operating Segments | Other Stabilized
Segment Reporting
Total revenue	45,599	20,958
Continuing Operations | Non-allocated
Segment Reporting
Total revenue	$ 752	$ 877