SEGMENT DISCLOSURE - Reconciliation Of Segment Operating Income (Details) - USD ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Segment disclosure
Asset management and other fees to related parties	$ (7,863,000)	$ (8,376,000)	$ (16,563,000)	$ (17,007,000)
Interest expense	(9,513,000)	(7,295,000)	(19,286,000)	(14,110,000)
General and administrative	(1,647,000)	(2,131,000)	(3,326,000)	(4,073,000)
Transaction costs	(11,615,000)	(118,000)	(11,628,000)	(267,000)
Depreciation and amortization	(14,761,000)	(18,480,000)	(31,992,000)	(36,538,000)
Impairment of real estate	(13,100,000)	0	(13,100,000)	0
Gain on sale of real estate	116,283,000	0	304,017,000	24,739,000
INCOME (LOSS) FROM CONTINUING OPERATIONS BEFORE PROVISION FOR INCOME TAXES	91,834,000	(339,000)	286,161,000	26,144,000
Provision for income taxes	(462,000)	(471,000)	(854,000)	(661,000)
NET INCOME (LOSS) FROM CONTINUING OPERATIONS	91,372,000	(810,000)	285,307,000	25,483,000
Discontinued Operations
Income from operations of assets held for sale	0	1,668,000	0	2,358,000
NET INCOME FROM DISCONTINUED OPERATIONS	0	1,668,000	0	2,358,000
NET INCOME	91,372,000	858,000	285,307,000	27,841,000
Net income attributable to noncontrolling interests	(9,000)	(9,000)	(14,000)	(12,000)
NET INCOME ATTRIBUTABLE TO THE COMPANY	91,363,000	849,000	285,293,000	27,829,000
Reportable segments
Segment disclosure
INCOME (LOSS) FROM CONTINUING OPERATIONS BEFORE PROVISION FOR INCOME TAXES	32,469,000	34,271,000	74,584,000	69,613,000
Corporate and Reconciling Items
Segment disclosure
Asset management and other fees to related parties	(7,079,000)	(7,492,000)	(14,935,000)	(15,193,000)
Interest expense	(9,568,000)	(7,302,000)	(19,199,000)	(13,928,000)
General and administrative	(795,000)	(1,218,000)	(1,586,000)	(2,282,000)
Transaction costs	(11,615,000)	(118,000)	(11,628,000)	(267,000)
Depreciation and amortization	(14,761,000)	(18,480,000)	(31,992,000)	(36,538,000)
Impairment of real estate	(13,100,000)	0	(13,100,000)	0
Gain on sale of real estate	$ 116,283,000	$ 0	$ 304,017,000	$ 24,739,000