SCHEDULE III REAL ESTATE AND ACCUMULATED DEPRECIATION - Analysis of Carrying Amount of Real Estate Properties and Accumulated Depreciation (Details) - USD ($) $ in Thousands	3 Months Ended		12 Months Ended
	Dec. 31, 2014	Jun. 30, 2014	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Real Estate Properties
Balance at the beginning of the year			$ 5,728,443	$ 5,537,165	$ 7,829,409
Additions			68,118	70,963	231,485
Loss on asset impairment	$ (167,100)	$ (22,700)	(17,162)	(185,067)	(124,253)
Deconsolidation of SIR					(1,446,781)
Properties reclassified to discontinued operations					(552,024)
Properties reclassified to continuing operations				341,024
Disposals			(1,892,047)	(29,219)	(140,783)
Balance at the end of the year	5,728,443		3,887,352	5,728,443	5,537,165
Accumulated Depreciation
Balance at the beginning of the year			1,030,445	895,059	1,007,606
Additions			144,844	164,815	176,777
Loss on asset impairment			0	(6,423)	(185,795)
Deconsolidation of SIR					(56,023)
Properties reclassified to discontinued operations					(15,471)
Disposals			(276,350)	(28,730)	(32,035)
Properties reclassified to continuing operations				5,724
Balance at the end of the year	$ 1,030,445		$ 898,939	1,030,445	895,059
Real Estate
Real Estate Properties
Loss on asset impairment				$ (191,490)	$ (384,141)