REDEEMABLE PREFERRED STOCK - Narrative (Details) - USD ($)			3 Months Ended		4 Months Ended	21 Months Ended
	Nov. 21, 2017	Jul. 01, 2016	Mar. 31, 2018	Mar. 31, 2017	Mar. 31, 2018	Mar. 31, 2018	Dec. 31, 2017
Class of Stock [Line Items]
Preferred stock redemption, trading days prior to redemption			20 days
Costs specifically identifiable to the offering						$ 3,322,000
Non issuance specific costs						4,013,000
Deferred rent receivable reclassified to temporary equity			$ 3,302,000
Accumulated cash dividends			$ 3,152,000	$ 0
Series A Preferred Stock
Class of Stock [Line Items]
Preferred stock redemption, trading days prior to redemption			20 days
Proceeds from issuance of preferred stock						41,736,000
Costs specifically identifiable to the offering						3,262,000
Deferred rent receivable reclassified to temporary equity						$ 186,000
Number of shares redeemed			2,945
Cumulative dividend rate			5.50%
Dividend per share per year (in usd per share)			$ 0.34375
Preferred stock, shares issued (in shares)			1,533,088		1,533,088	1,533,088	1,225,734
Preferred stock, par value (in usd per share)			$ 0.001		$ 0.001	$ 0.001	$ 0.001
Preferred stock, liquidation preference per share (in usd per share)			$ 25.00		$ 25.00	$ 25.00	$ 25.00
Series A Preferred Unit
Class of Stock [Line Items]
Units issued (in shares)			1,677,786		1,677,786	1,677,786
Proceeds from issuance of preferred stock and warrants						$ 41,945,000
Warrant
Class of Stock [Line Items]
Net proceeds from issuance of warrants						209,000
Costs specifically identifiable to the offering						60,000
Deferred rent receivable reclassified to temporary equity						$ 1,000
Series L Preferred Unit
Class of Stock [Line Items]
Preferred stock, shares issued (in shares)	808,074
Series L Preferred Stock
Class of Stock [Line Items]
Proceeds from issuance of preferred stock and warrants	$ 229,251,000
Costs specifically identifiable to the offering	15,928,000
Non issuance specific costs	$ 2,532,000
Number of shares redeemed			0
Cumulative dividend rate			5.50%
Dividend per share per year (in usd per share)			$ 1.56035
Preferred stock, shares issued (in shares)	8,080,740		8,080,740		8,080,740	8,080,740	8,080,740
Preferred stock, par value (in usd per share)			$ 0.001		$ 0.001	$ 0.001	$ 0.001
Preferred stock, liquidation preference per share (in usd per share)			$ 28.37		$ 28.37	$ 28.37	$ 28.37
Preferred stock discount	$ 2,946,000
Failure to declare or pay distributions, temporary increase per year			1.00%
Failure to declare or pay distributions, temporary increase per year, maximum increase			8.50%
Accumulated cash dividends			$ 3,152,000		$ 4,588,000
Minimum Fixed Charge Coverage Ratio			125.00%
Registration Statement
Class of Stock [Line Items]
Maximum amount of offering		$ 900,000,000
Warrant right to purchase a share of Common Stock (in shares)		0.25
Maximum number of units in offering (in shares)		36,000,000
Registration Statement | Series A Preferred Stock
Class of Stock [Line Items]
Redeemable preferred stock, par value (in usd per share)		$ 0.001
Preferred stock, stated value (in usd per share)		$ 25
Registration Statement | Series L Preferred Stock
Class of Stock [Line Items]
Number of shares per unit	10
Preferred stock, par value (in usd per share)	$ 0.001
Preferred stock, liquidation preference per share (in usd per share)	$ 28.37
Preferred Stock, Redemption Period, Year Two | Series A Preferred Stock
Class of Stock [Line Items]
Preferred stock, redemption fee		13.00%
Preferred Stock, Redemption Period, After Year Two, Before Year Five | Series A Preferred Stock
Class of Stock [Line Items]
Preferred stock, redemption fee		10.00%
Preferred Stock, Redemption Period, After Year Five | Series A Preferred Stock
Class of Stock [Line Items]
Preferred stock, redemption fee		0.00%