SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Affordable Housing Fund Investment (Details) $ in Thousands	12 Months Ended
Dec. 31, 2015 USD ($) limited_partnership	Dec. 31, 2014 USD ($)
Schedule of Equity Method Investments [Line Items]
Number of limited partnerships \| limited_partnership	2
Affordable Housing Partnerships
Schedule of Equity Method Investments [Line Items]
Gross investment in limited partnership	$ 9,200	$ 9,000
Original investment in limited partnership	9,500	9,500
Unfunded amount in limited partnership	$ 439
Compliance period to fully utilize tax credits	15 years
Investment amortization	$ 727	802
Affordable Housing Partnerships \| Investment Tax Credit Carryforward
Schedule of Equity Method Investments [Line Items]
Future federal and state tax credit amounts to be generated	3,100	3,800
Unused tax credit carryforward	$ 0	$ 0
Affordable Housing Partnerships \| Minimum
Schedule of Equity Method Investments [Line Items]
Ownership percentage of limited partnership	8.00%
Affordable Housing Partnerships \| Maximum
Schedule of Equity Method Investments [Line Items]
Ownership percentage of limited partnership	14.00%

Affordable Housing Tax Credits and Other Tax Benefits, Estimated Future Amount

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Amortization Method Qualified Affordable Housing Project Investments, Gross

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Amortization Method Qualified Affordable Housing Project Investments, Original Investment

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Equity Method Investment, Number of Limited Partnerships

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Equity Method Investments, Compliance Period to Fully Utilize Tax Credits

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- Definition

Amount of amortization expense of investment in qualified affordable housing projects.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 323
-SubTopic 740
-Section 50
-Paragraph 2
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=49127445&loc=SL49122993-202985

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The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 323
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=6382943&loc=d3e33918-111571

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Amount of commitment or contingent commitments to qualified affordable housing project investments.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 323
-SubTopic 740
-Section 50
-Paragraph 2
-Subparagraph (e)
-URI http://asc.fasb.org/extlink&oid=49127445&loc=SL49122993-202985

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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.

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The amount of the tax credit carryforward, before tax effects, available to reduce future taxable income under enacted tax laws.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32559-109319

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Carryforwards
-URI http://asc.fasb.org/extlink&oid=6506874

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