Segment Reporting (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Segment Reporting Information [Line Items]
Total revenue	$ 561,743	$ 576,405	$ 1,112,879	$ 1,178,056
Reconciliation of NOI to net income
Net income	447,977	170,869	590,211	338,875
Indirect operating expenses, net of corporate income	24,318	23,407	48,788	46,206
Other Nonoperating Income (Expense)	1,653	388	1,483	3,722
Interest Expense	56,104	53,399	108,717	109,313
(Gain) loss on extinguishment of debt, net	0	(268)	122	(9,438)
General and administrative expense	18,465	15,573	35,817	32,893
Income from investments in unconsolidated entities	(26,559)	(512)	(26,092)	(1,687)
Depreciation expense	184,472	176,249	367,769	354,160
Income tax expense (benefit)	10	(1,133)	(745)	(1,042)
Casualty and impairment loss	1,177	0	1,177	0
Gain on sale of communities	(334,569)	(35,295)	(388,296)	(59,731)
Gain on other real estate transactions, net	(32)	(156)	(459)	(199)
Net for-sale condominium activity	647	(1,348)	1,560	(4,808)
Net operating income from real estate assets sold or held for sale	(4,749)	(13,581)	(10,549)	(28,572)
Net operating income	$ 368,914	$ 388,128	$ 729,259	$ 798,568
Non-Apartment Components Of Mixed-Use Communities And Other Nonresidential Operations | Operating Income (Loss) | Product Concentration Risk
Segment Reporting Information [Line Items]
Concentration Risk, Percentage	1.50%	0.50%	1.50%	1.10%