Supplemental Information to Statements of Cash Flows - Schedule of Supplemental Information to Statements of Cash Flows (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018	Dec. 31, 2018	Dec. 31, 2017
Supplemental Cash Flows [Line Items]
Restricted cash reserves		$ 5,100		$ 3,200
Rangers Sub I, LLC
Supplemental Cash Flows [Line Items]
Cash and cash equivalents	$ 11,155	13,715	$ 11,155	21,351
Restricted cash reserves	4,957	5,081	4,957	3,211
Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents	16,112	18,796	16,112	$ 24,562	$ 18,031
Interest paid		18,146	35,340
Interest Paid, Related Party		2,335	0
Income taxes refunded		0	(262)
Operating Lease, Payments		4,048
Gross Proceeds from Sale of Real Estate Held-for-investment		147,377	119,200
Transaction costs		(1,452)	(2,650)
Noncash Divestiture of Other Assets	$ 0	(536)
Proceeds from Sale of Real Estate Held-for-investment		145,389	116,550
Accrued capital expenditures		$ 1,201	$ 6,010