INVESTMENT IN UNCONSOLIDATED JOINT VENTURES - Investments in Unconsolidated Joint Ventures (Details) - USD ($) $ in Thousands	Dec. 31, 2017		Dec. 31, 2016
Schedule of Equity Method Investments [Line Items]
Investment in unconsolidated joint ventures	$ 35,441	[1]	$ 34,025
Grace Lake JV, LLC
Schedule of Equity Method Investments [Line Items]
Investment in unconsolidated joint ventures	4,908		3,719
24 Second Avenue Holdings LLC
Schedule of Equity Method Investments [Line Items]
Investment in unconsolidated joint ventures	$ 30,533		$ 30,306

[1] Includes amounts relating to consolidated variable interest entities. See Note 3.