INVESTMENTS IN REAL ESTATE SECURITIES - Summary of the Geographic Distribution of the Collateral Securing Non-Agency RMBS (Footnote) (Details) $ in Millions	Sep. 30, 2015 USD ($)
Servicer Advances [Member] \| Bonds [Member]
Schedule of Available-for-sale Securities [Line Items]
Face amount of investment	$ 122.0

Nominal or face amount on the investment owned.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Underlying

-URI http://asc.fasb.org/extlink&oid=6527499

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 10

-Paragraph 1

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=6431724&loc=d3e32938-113948

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 20

-Section 10

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6438156&loc=d3e57880-113973

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