SCHEDULE III Real Estate and Accumulated Depreciation - Accumulated Depreciation (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, Accumulated Depreciation [Roll Forward]
Balance at beginning of year	$ 1,044,689	$ 949,630	$ 883,445
Depreciation	96,263	95,415	67,652
Disposals	(388)	(356)	(1,467)
Balance at end of year	$ 1,140,564	$ 1,044,689	$ 949,630