Schedule III - Real Estate and Accumulated Depreciation (Details) - Reconciliation of Accumulated Depreciation - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
SEC Schedule, 12-28, Real Estate Companies, Investment in Real Estate, Accumulated Depreciation [Roll Forward]
Balance	$ 329,207	$ 260,115	$ 193,021
Depreciation expenses	82,419	81,107	72,725
Properties sold during the year	10,775	3,551	0
Property assets fully depreciated and written off	(9,935)	(8,464)	(5,631)
Balance	$ 390,916	$ 329,207	$ 260,115