Schedule III - Real Estate and Accumulated Depreciation - Reconciliation of Investment Properties (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
SEC Schedule, 12-28, Real Estate Companies, Investment in Real Estate [Roll Forward]
Balance, beginning of year	$ 3,133,966	$ 3,109,433	$ 2,884,486
Acquisition of new properties	316,428	0	0
Improvements	89,426	104,060	255,924
Disposals	(38,903)	(79,527)	(30,977)
Balance, end of year	3,500,917	$ 3,133,966	$ 3,109,433
Aggregate cost of investment properties for federal income tax purpose	$ 3,300,000