Reportable Segments - Reconciliation of NOI from Rental Real Estate Specific to Continuing Operations (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Segment Reporting Reconciling Item For Operating Profit Loss From Segment To Consolidated [Line Items]
Rental income	$ 687,030	$ 598,059	$ 1,340,378	$ 1,195,661
Property and maintenance expense	(116,355)	(107,746)	(241,229)	(224,800)
Real estate taxes and insurance expense	(101,850)	(97,401)	(202,538)	(200,871)
Operating income	309,934	376,844	459,672	512,404
Same Store, Non-same Store and Other
Segment Reporting Reconciling Item For Operating Profit Loss From Segment To Consolidated [Line Items]
Rental income	687,030	598,059	1,340,378	1,195,661
Property and maintenance expense	(116,355)	(107,746)	(241,229)	(224,800)
Real estate taxes and insurance expense	(101,850)	(97,401)	(202,538)	(200,871)
Total operating expenses	(218,205)	(205,147)	(443,767)	(425,671)
Operating income	$ 468,825	$ 392,912	$ 896,611	$ 769,990

The aggregate costs of keeping the property in good condition but that do not appreciably prolong the life or increase the value of the property.

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