DERIVATIVES - Summary of Derivative Financial Instruments and Balances (Details) - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014
Derivatives, Fair Value [Line Items]
Inerest-bearing deposit liability	$ 1,050,781	$ 823,585
Estimate Fair Value Gain	18,555	11,399
Estimate Fair Value Loss	(18,836)	(11,916)
Fair Value Hedges \| Pay fixed interest rate swaps with counterparty \| Accrued interest and other liabilities
Derivatives, Fair Value [Line Items]
Inerest-bearing deposit liability	6,261	8,739
Estimate Fair Value Gain	0	0
Estimate Fair Value Loss	(235)	(440)
Fair Value Hedges \| Matched interest rate swaps \| Accrued interest and other liabilities
Derivatives, Fair Value [Line Items]
Inerest-bearing deposit liability	522,260	407,423
Estimate Fair Value Gain	0	249
Estimate Fair Value Loss	(18,601)	(11,227)
Fair Value Hedges \| Matched interest rate swaps \| Accrued interest and other assets
Derivatives, Fair Value [Line Items]
Inerest-bearing deposit liability	522,260	407,423
Estimate Fair Value Gain	18,555	11,150
Estimate Fair Value Loss	$ 0	$ (249)

Aggregate notional amount specified by the derivative(s). Expressed as an absolute value.

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Article 12

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-Publisher FASB

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