Schedule III (Consolidated) - Real Estate and Accumulated Depreciation - Reconciliation of Real Estate Owned (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
SEC Schedule III, Reconciliation of real estate owned
Balance at beginning of the year	$ 418,494	$ 404,376	$ 381,969
Amounts capitalized	109,699	43,306	39,261
Impairments		(99)	(714)
Cost of real estate sold	(23,608)	(18,928)	(14,274)
Amounts retired or adjusted	447	(10,161)	(1,866)
Balance at the end of the year	$ 505,032	$ 418,494	$ 404,376