MORTGAGE LOAN RECEIVABLES (Details) $ in Thousands	6 Months Ended
Jun. 30, 2015 USD ($) loan	Jun. 30, 2014 loan	Dec. 31, 2014 USD ($) loan
Mortgage Loans on Real Estate [Line Items]
Loans receivable with fixed rates of interest	$ 385,400		$ 231,900
Percentage of loans receivable with fixed rates of interest	22.10%		15.20%
Number of mortgage loans impaired \| loan	0		0
Unamortized discounts included in mortgage loan receivables held for investment, at amortized cost	$ 4,200		$ 4,200
Carrying value, net	2,248,518		1,939,008
Mortgage loan receivables held for investment, at amortized cost
Mortgage Loans on Real Estate [Line Items]
Loans receivable with fixed rates of interest	$ 1,400,000		$ 1,300,000
Percentage of loans receivable with fixed rates of interest	77.90%		84.80%
Carrying value, net	$ 1,740,808		$ 1,521,053
Loan on non-accrual status
Mortgage Loans on Real Estate [Line Items]
Unamortized discounts included in mortgage loan receivables held for investment, at amortized cost	$ 3,500		3,500
Number of loans on non-accrual status \| loan	1	1
Carrying value, net	$ 4,600		4,600
Mortgage loan receivables held for sale
Mortgage Loans on Real Estate [Line Items]
Loans receivable with fixed rates of interest	$ 507,700		$ 418,000
Percentage of loans receivable with fixed rates of interest	100.00%		100.00%
Carrying value, net	$ 507,710		$ 417,955

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.

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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

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- Definition

The balance represents the amount of loans that are secured by real estate mortgages, offset by the reserve to cover probable credit losses on the loan portfolio.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 944

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.7-03.1(c))

-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 1

-Subparagraph c

-Article 7

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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.

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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

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 205

-SubTopic 10

-Section S99

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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

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