MORTGAGE LOAN RECEIVABLES (Details)	6 Months Ended
Jun. 30, 2016 USD ($) loan	Jun. 30, 2015 loan	Dec. 31, 2015 USD ($) loan
Mortgage Loans on Real Estate [Line Items]
Loans receivable with fixed rates of interest	$ 315,000,000		$ 343,200,000
Percentage of loans receivable with fixed rates of interest	20.40%		19.70%
Unamortized discounts included in mortgage loan receivables held for investment, at amortized cost	$ 600,000		$ 700,000
Number of mortgage loans impaired \| loan	0		0
Mortgage loan receivables held for investment, at amortized cost
Mortgage Loans on Real Estate [Line Items]
Loans receivable with fixed rates of interest	$ 1,200,000,000		$ 1,400,000,000
Percentage of loans receivable with fixed rates of interest	79.60%		80.30%
Number or loans in default \| loan	2
Loans in default, carrying value	$ 26,900,000
Impairment recorded on defaulted loans	0
Mortgage loan receivables held for sale
Mortgage Loans on Real Estate [Line Items]
Loans receivable with fixed rates of interest	$ 583,500,000		$ 571,800,000
Percentage of loans receivable with fixed rates of interest	100.00%		100.00%
Loan on non-accrual status
Mortgage Loans on Real Estate [Line Items]
Number of loans on non-accrual status \| loan	0	0

Loans Receivable with Fixed Rates of Interest, Percentage

No definition available.

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- Definition

Represents the number of mortgage loans individually impaired.

+ References

No definition available.

+ Details

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- Definition

Number of financing receivables that have been modified by troubled debt restructurings within the previous 12 months and for which there was a payment default.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 34
-URI http://asc.fasb.org/extlink&oid=49124121&loc=SL6953682-111524

+ Details

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- Definition

Amount of investment related to financing receivables modified by troubled debt restructurings within the previous 12 months, for which there was a payment default.

+ References

+ Details

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- Definition

Reflects the amount of additional interest income that would have been recorded if impaired or nonperforming loans were instead current, in compliance with their original terms, and outstanding throughout the reporting period or since origination (if held for part of the period).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 40
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=25495931&loc=d3e18794-111554

+ Details

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- Definition

Amount of loan with fixed rate of interest.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=28367877&loc=d3e4428-111522

+ Details

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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- Definition

Indicates the number of mortgages under each classification.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 948
-SubTopic 310
-Section S99
-Paragraph 1
-Subparagraph (SX 210.12-29.3)
-URI http://asc.fasb.org/extlink&oid=6589523&loc=d3e617274-123014

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 205
-SubTopic 10
-Section S99
-Paragraph 6
-Subparagraph (SX 210.5-04.(c) Schedule IV)
-URI http://asc.fasb.org/extlink&oid=27047687&loc=d3e5864-122674

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- Definition

Amount of deferred fees paid by borrowers and unamortized costs incurred to originate loans and leases, unamortized loan commitments and loan syndication fees, and premiums over or discounts from face amounts of loans that are being amortized into income as an adjustment to yield. Excludes amounts for loans and leases covered under loss sharing agreements.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 20
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6378536&loc=d3e10092-111533

+ Details

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- Details

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- Details

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