INVESTMENT IN UNCONSOLIDATED JOINT VENTURE (Narrative) (Details) $ in Thousands		3 Months Ended			12 Months Ended
	Nov. 01, 2016 USD ($) facility	Dec. 31, 2018 USD ($) facility	Jun. 30, 2018 USD ($) facility	Dec. 31, 2017 USD ($) facility	Dec. 31, 2018 USD ($) facility property	Dec. 31, 2017 USD ($) facility	Dec. 31, 2016 USD ($) facility
Schedule of Equity Method Investments [Line Items]
Investment in unconsolidated joint venture		$ 31,045		$ 36,516	$ 31,045	$ 36,516
Assets management fees recognized					1,800	2,000	$ 300
Proceeds from Sale of Property, Plant, and Equipment					164,000
Loss (gain) on assets sold - net		$ (15,500)		$ (46,400)	(24,800)	(53,900)	(50,200)
Impairment of Real Estate					$ 35,014	$ 99,070	$ 58,726
Number Of Facilities Sold | facility		14		32	78	52	38
Skilled Nursing Facilities
Schedule of Equity Method Investments [Line Items]
Proceeds from Sale of Property, Plant, and Equipment			$ 78,000			$ 43,300
Loss (gain) on assets sold - net					$ 4,600	$ (17,500)
Impairment of Real Estate					$ 4,200
Number Of Facilities Sold | facility			12
Second Spring Healthcare Investments [Member]
Schedule of Equity Method Investments [Line Items]
Investment in unconsolidated joint venture	$ 50,000
Percentage of ownership interest	15.00%
Second Spring Healthcare Investments [Member] | Skilled Nursing Facilities
Schedule of Equity Method Investments [Line Items]
Number of properties acquired | facility	64
Payments to acquire facilities	$ 1,100,000
Number Of Facilities Sold | property					13
Second Spring Healthcare Investments [Member] | Affiliates Of Lindsey Goldberg Llc [Member]
Schedule of Equity Method Investments [Line Items]
Percentage of ownership interest	85.00%