MORTGAGE LOAN RECEIVABLES - Activity in Loan Portfolio (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2017	Mar. 31, 2016
Activity in loan portfolio
Realized gain on sale of mortgage loan receivables	$ (999)	$ 7,830
Transfer between held for investment and held for sale	119,952	0
Loan loss provision	0	(150)
Loans held for sale transferred loan held for investment, book value	120,000
Loans held for sale transferred to loans held for investments, fair value	$ 120,000
Loans transferred from held for sale to held for investments, remaining maturity	3 years
Mortgage loan receivables held for investment, at amortized cost
Activity in loan portfolio
Balance at the beginning of the period	$ 1,996,095	1,738,645
Origination of mortgage loan receivables	249,829	49,735
Repayment of mortgage loan receivables	(68,251)	(218,410)
Proceeds from sales of mortgage loan receivables		0
Realized gain on sale of mortgage loan receivables	0	0
Transfer between held for investment and held for sale	119,952
Accretion/amortization of discount, premium and other fees	2,468	3,013
Loan loss provision		(150)
Balance at the end of the period	2,300,093	1,572,833
Provision for Loan and Lease Losses	4,000	3,900
Mortgage loan receivables held for sale
Activity in loan portfolio
Balance at the beginning of the period	357,882	571,764
Origination of mortgage loan receivables	279,898	91,027
Repayment of mortgage loan receivables	(247)	(524)
Proceeds from sales of mortgage loan receivables		(316,766)
Realized gain on sale of mortgage loan receivables	(999)	7,830
Transfer between held for investment and held for sale	(119,952)
Accretion/amortization of discount, premium and other fees	0	0
Loan loss provision		0
Balance at the end of the period	516,582	$ 353,331
Realized losses on loans recorded as other than temporary impairments	$ 1,000

Loans From Held For Sale Transferred To Portfolio Loans, Remaining Maturity

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- Definition

Loans Held-for-sale Transferred to Portfolio Loans, Carrying Amount

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No definition available.

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Loans Held-for-sale Transferred to Portfolio Loans, Fair Value

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No definition available.

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- Definition

Represents the amount of accretion/ amortization of discount, premium and other fees on mortgage loans on real estate accreted/ amortized during the reporting period.

+ References

No definition available.

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- Definition

Transfer To (From) Loans Held-for-sale to Portfolio Loans

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No definition available.

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Amount of increase (decrease) of allowance reserve for credit loss.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.7(d))
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- Definition

The net gain (loss) resulting from a sale of loans, including adjustments to record loans classified as held-for-sale at the lower-of-cost-or-market and fair value adjustments to loan held for investment purposes.

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- Definition

Total carrying amount of mortgage loans as of the balance sheet date.

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- Definition

The amount of principal collected on mortgage loans on real estate during the reporting period.

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- Definition

The carrying amount of mortgage loans on real estate that were sold during the reporting period.

+ References

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- Definition

Total amount of new mortgage loans on real estate during the reporting period.

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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No definition available.

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- Definition

The cumulative amount of credit losses recognized in earnings related to debt securities held for which a portion of an other than temporary impairment (OTTI) was recognized in other comprehensive income (a component of shareholders' equity).

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- Definition

Amount of expense related to estimated loss from loan and lease transactions.

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