Combined Guarantor Subsidiaries - Combined Statements of Operations - Summary (Details) - USD ($) $ in Thousands	3 Months Ended						9 Months Ended
	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Sep. 30, 2019	Sep. 30, 2018
REVENUES:
Rental revenues				$ 200,311				$ 620,608
Other	$ 4,419			3,909			$ 14,344	13,046
Total revenues	187,251			206,878			578,658	641,676
OPERATING EXPENSES:
Property operating	(27,344)			(30,004)			(82,856)	(92,357)
Depreciation and amortization	(64,168)			(71,945)			(198,438)	(217,261)
Real estate taxes	(18,699)			(19,433)			(57,766)	(61,737)
Maintenance and repairs	(10,253)			(11,475)			(34,327)	(36,713)
Loss on impairment	(135,688)			(14,600)			(202,121)	(84,644)
Other	(7)			(38)			(41)	(377)
Total operating expenses	(245,938)			(163,546)			(689,912)	(540,934)
OTHER INCOME (EXPENSES):
Interest and other income	1,367			283			2,212	714
Interest expense	(50,515)			(55,194)			(156,995)	(163,164)
Gain on extinguishment of debt	0			0			71,722	0
Gain (loss) on sales of real estate assets	8,056			7,880			13,811	15,998
Total other income (expenses)	(33,347)			(46,303)			(57,277)	(134,350)
Net loss	(92,034)			(2,971)			(168,531)	(33,608)
Guarantor Subsidiaries
REVENUES:
Rental revenues	67,495			77,067			206,083	232,749
Other	1,833			1,588			5,104	4,935
Total revenues	69,328			78,655			211,187	237,684
OPERATING EXPENSES:
Property operating	(10,713)			(11,875)			(32,263)	(35,629)
Depreciation and amortization	(24,681)			(24,481)			(71,499)	(73,587)
Real estate taxes	(6,523)			(7,338)			(19,318)	(21,451)
Maintenance and repairs	(4,005)			(4,288)			(12,846)	(13,364)
Loss on impairment	0			0			(22,770)	0
Other	(12)			(5)			(639)	(40)
Total operating expenses	(45,934)			(47,987)			(159,335)	(144,071)
OTHER INCOME (EXPENSES):
Interest and other income	1,022			1,857			3,049	6,077
Interest expense	(3,400)			(6,129)			(10,797)	(18,270)
Gain on extinguishment of debt	0			0			61,796	0
Gain (loss) on sales of real estate assets	20			698			20	2,406
Total other income (expenses)	(2,358)			(3,574)			54,068	(9,787)
Net loss	$ 21,036	$ 22,775	$ 62,109	$ 27,094	$ 27,117	$ 29,615	$ 105,920	$ 83,826