STOCKHOLDERS' EQUITY (Details) - USD ($) $ / shares in Units, $ in Thousands													12 Months Ended
	Mar. 08, 2017	Dec. 31, 2016	Dec. 06, 2016	Sep. 14, 2016	Sep. 12, 2016	Jun. 10, 2016	May 16, 2016	Mar. 08, 2016	Dec. 10, 2015	Sep. 14, 2015	Jun. 12, 2015	Mar. 06, 2015	Dec. 31, 2016	Dec. 31, 2014	Apr. 22, 2016	Dec. 31, 2015
Dividend declared
Dividends declared, common (in usd per share)			$ 0.21875		$ 0.21875	$ 0.21875		$ 0.21875	$ 0.21875	$ 0.21875	$ 0.21875	$ 0.21875
Purchase price, repurchase of common stock													$ 290,134	$ 3
Subsequent event
Dividend declared
Dividends declared, common (in usd per share)	$ 0.21875
Common Stock
Dividend declared
Cash tender offer number of shares							10,000,000
Price per share of cash tender offer (in usd per share)							$ 21.00
Repurchase of common stock (in shares)							10,000,000
Aggregate purchase price							$ 210,000
Tender offer fees and expenses							$ 301
Shares repurchased as percent to outstanding shares							10.24%
Common Stock | Urban Partners II, LLC
Dividend declared
Repurchase of common stock (in shares)				3,628,116
Aggregate purchase price							$ 208,140
Purchase price, repurchase of common stock				$ 79,819
Share price of stock repurchased (in usd per share)				$ 22.00
Series A Preferred Stock
Dividend declared
Warrant right to purchase a share of Common Stock															0.25
Preferred stock, shares issued		61,435											61,435			0
Warrant
Dividend declared
Net Proceeds From Issuance Of Preferred Stock And Preference Stock		$ 5
Registration statement
Dividend declared
Premium of the exercise price of the warrant as a percent to net asset value of common stock															15.00%