Summary of Critical and Significant Accounting Policies - Narrative (Details)	12 Months Ended
	Dec. 31, 2022 USD ($) property investment community partnership shares	Dec. 31, 2021 USD ($) property shares	Dec. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)
Accounting Policies [Abstract]
Limited partner - ownership percentage	3.40%	3.40%
Threshold useful life of assets for capitalization	1 year
Acquired in-place lease value, net	$ 7,400,000	$ 8,900,000
Number of properties held-for-sale | property	0	0
Impairment loss	$ 0	$ 0	$ 1,825,000
Impairment loss from unconsolidated co-investment	$ 2,100,000	0	0
Lease term, minimum	9 months
Lease term, maximum	12 months
Original maturities highly liquid investments term classification as cash equivalents, maximum	3 months
Equity securities, FV-NI	$ 200,000	800,000
Proceeds from sale and maturities of marketable securities	71,200,000	16,600,000	113,500,000
Marketable securities, realized gain (loss)	12,400,000	3,400,000	2,100,000
Unrealized gain (loss) on equity securities recognized through income	(57,983,000)	33,104,000	12,515,000
Capitalized internal costs related to development and redevelopment projects	20,400,000	23,600,000	31,400,000
Fixed rate debt carrying amount	5,700,000,000	5,700,000,000
Fixed rate debt fair value	5,200,000,000	6,000,000,000
Variable rate debt carrying amount	274,200,000	564,900,000
Variable rate debt fair value	$ 273,200,000	561,700,000
DownREIT limited partnerships consolidated by company (in partnerships) | partnership	18
Communities within DownREIT partnerships (in communities) | community	9
Number of consolidated co-investments that now meet the definition of a VIE | investment	6
Assets related to variable interest entities net of intercompany eliminations	$ 939,400,000	909,300,000
Liabilities related to variable interest entities net of intercompany eliminations	324,300,000	320,100,000
Noncontrolling interests in VIE	$ 121,500,000	$ 122,400,000
Number of common stock shares per unit basis (in shares) | shares	1
Units of limited partnership interest amount (in shares) | shares	938,513	978,854
Redemption value of variable interest entities	$ 198,900,000	$ 344,800,000
Redeemable noncontrolling interest	27,150,000	34,666,000	32,239,000	$ 37,410,000
Redeemable noncontrolling interest, units of limited partners' interests in DownREIT VIEs	9,200,000	7,700,000
Noncontrolling interest in limited partnerships	97,000,000	97,400,000
Employee retention credit	$ 4,100,000	$ 4,200,000	$ 0