SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Narrative (Details) $ in Thousands	9 Months Ended
Sep. 30, 2016 USD ($) variable_interest_entity Investment	Dec. 31, 2015 USD ($)
Debt Instrument [Line Items]
Number of VIEs \| variable_interest_entity	2
Number of investments in loans accounted for as real estate joint ventures \| Investment	0
Deferred financing costs	$ 17,236
Accounting Standards Update 2015-03 [Member] \| Prepaid expenses, deferred financing costs and other assets, net [Member]
Debt Instrument [Line Items]
Deferred financing costs		$ (17,300)

Amount, after accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=64930785&loc=d3e28555-108399

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.17)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant