Schedule III - Real Estate and Accumulated Depreciation - Summary of Changes in Real Estate (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Changes in total real estate
Balance, beginning of year	$ 26,026,896	$ 25,386,425	$ 28,542,697
Acquisitions and development	855,254	710,960	832,803
Improvements	192,661	204,113	174,981
Dispositions and other	(563,789)	(274,602)	(4,164,056)
Balance, end of year	$ 26,511,022	$ 26,026,896	$ 25,386,425