Schedule III - Real Estate and Accumulated Depreciation - Historical Cost Real Estate Reconciliation (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
SEC Schedule, 12-28, Real Estate Companies, Investment in Real Estate [Roll Forward]
Total real estate held for investment, beginning of year	$ 9,628,773	$ 8,426,632	$ 7,417,777
Acquisitions	0	460,512	581,671
Improvements, etc.	645,170	890,654	724,016
Total additions during period	645,170	1,351,166	1,305,687
Cost of real estate sold	(44,070)	(120,788)	(286,623)
Other	(39,827)	(28,237)	(10,209)
Total deductions during period	(83,897)	(149,025)	(296,832)
Total real estate held for investment, end of year	$ 10,190,046	$ 9,628,773	$ 8,426,632