Reportable Segments - Reconciliation of NOI from Rental Real Estate Specific to Continuing Operations (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2022	Mar. 31, 2021
Segment Reporting Reconciling Item For Operating Profit Loss From Segment To Consolidated [Line Items]
Rental income	$ 653,348	$ 597,602
Property and maintenance expense	(124,874)	(117,054)
Real estate taxes and insurance expense	(100,688)	(103,470)
Operating income	149,738	135,560
Same Store, Non-same Store and Other
Segment Reporting Reconciling Item For Operating Profit Loss From Segment To Consolidated [Line Items]
Rental income	653,348	597,602
Property and maintenance expense	(124,874)	(117,054)
Real estate taxes and insurance expense	(100,688)	(103,470)
Total operating expenses	(225,562)	(220,524)
Operating income	$ 427,786	$ 377,078

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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