FAIR VALUE ACCOUNTING AND MEASUREMENT (Asset Inputs) (Details) (USD $)	3 Months Ended
Mar. 31, 2015	Dec. 31, 2014
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Securities—trading, Amortized Cost	$ 43,878,000us-gaap_TradingSecuritiesCost	47,480,000us-gaap_TradingSecuritiesCost
Available-for-sale Debt Securities, Amortized Cost Basis	393,831,000	411,424,000
TRUP CDO Securities [Member] \| Income approach, using discounted cash-flow model [Member] \| Level 3 [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Securities—trading, Amortized Cost	6,000,000
TPS Securities [Member] \| Income approach, using discounted cash-flow model [Member] \| Level 3 [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Asset gains (losses)	(43,000)
Securities—trading, Amortized Cost	19,000,000
Discount Rate, Description of Variable Rate Basis	three-month LIBOR	three-month LIBOR
Discount Rate, Basis Spread on Variable Rate Basis	5.00%	5.25%
TRUP CDO Security One [Member] \| TRUP CDO Securities [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Proceeds from Sale of Available-for-sale Securities, Debt	2,200,000
Available-for-sale Debt Securities, Amortized Cost Basis	2,900,000
Gain (Loss) on Sale of Debt Investments	(555,000)
Valuation Allowances and Reserves, Period Increase (Decrease)	1,200,000
TRUP CDO Security One [Member] \| Carrying Value \| TRUP CDO Securities [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Available-for-sale Securities, Debt Securities	1,700,000
Gain (Loss) on Sale of Debt Investments	642,000
TRUP CDO Security Two [Member] \| TRUP CDO Securities [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Proceeds from Sale of Available-for-sale Securities, Debt	109,000
Available-for-sale Debt Securities, Amortized Cost Basis	0
Valuation Allowances and Reserves, Period Increase (Decrease)	109,000
TRUP CDO Security Two [Member] \| TRUP CDO Securities [Member] \| Income approach, using discounted cash-flow model [Member] \| Level 3 [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Asset gains (losses)	$ (1,400,000)

Fair Value Inputs, Discount Rate, Basis Spread on Variable Rate Basis

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Fair Value Inputs, Discount Rate, Description of Variable Rate Basis

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- Definition

This item represents the cost of debt securities, which are categorized neither as held-to-maturity nor trading, net of adjustments including accretion, amortization, collection of cash, previous other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments recognized, as defined), and fair value hedge accounting adjustments, if any.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.2)

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (aa)

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- Definition

Amount of debt securities categorized neither as held-to-maturity nor trading.

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

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-Name Accounting Standards Codification

-Topic 942

-SubTopic 320

-Section 50

-Paragraph 2

-Subparagraph (b)-(g)

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- Definition

Amount of gain (loss) recognized in the income statement for financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 820

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(1)

-URI http://asc.fasb.org/extlink&oid=36462937&loc=d3e19207-110258

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- Definition

The difference between the carrying value and the sale price of debt securities, not separately or otherwise categorized as trading, available-for-sale, or held-to-maturity. This element refers to the gain (loss) included in earnings and not to the cash proceeds of the sale.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 28

-Subparagraph (b)

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 225

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-04.13(h))

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-Name Accounting Standards Codification

-Topic 944

-SubTopic 225

-Section S99

-Paragraph 1

-Subparagraph (SX 210.7-04.3(a))

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- Definition

The cash inflow associated with the sale of debt securities classified as available-for-sale securities.

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Investing Activities

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-Paragraph 12

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- Definition

Cost of investments in debt and equity securities and other forms of securities that provide ownership interests classified as trading.

+ References

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- Definition

Total increases or decreases in allowances and reserves, the valuation and qualifying accounts that are either netted against the cost of an asset (in order to value it at its carrying value) or that reflect a liability established to represent expected future costs.

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-Publisher FASB

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-Topic 235

-SubTopic 10

-Section S99

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