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, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Segment Reporting Reconciling Item For Operating Profit Loss From Segment To Consolidated [Line Items]
Rental income	$ 653,532	$ 669,374	$ 1,335,837	$ 1,331,676
Property and maintenance expense	(104,452)	(108,461)	(220,268)	(223,531)
Real estate taxes and insurance expense	(95,038)	(91,446)	(192,770)	(182,888)
Operating income	356,889	369,117	778,974	578,894
Same Store, Non-same Store and Other
Segment Reporting Reconciling Item For Operating Profit Loss From Segment To Consolidated [Line Items]
Rental income	653,532	669,374	1,335,837	1,331,676
Property and maintenance expense	(104,452)	(108,461)	(220,268)	(223,531)
Real estate taxes and insurance expense	(95,038)	(91,446)	(192,770)	(182,888)
Total operating expenses	(199,490)	(199,907)	(413,038)	(406,419)
Operating income	$ 454,042	$ 469,467	$ 922,799	$ 925,257

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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