DERIVATIVES - Summary of Derivative Financial Instruments and Balances (Details) - USD ($) $ in Thousands	Jun. 30, 2016	Dec. 31, 2015
Derivatives, Fair Value [Line Items]
Inerest-bearing deposit liability	$ 1,308,245	$ 1,098,132
Estimate Fair Value Gain	32,181	14,025
Estimate Fair Value Loss	(32,245)	(14,179)
Fair Value Hedges \| Pay fixed interest rate swaps with counterparty \| Accrued interest and other liabilities
Derivatives, Fair Value [Line Items]
Inerest-bearing deposit liability	1,643	5,216
Estimate Fair Value Gain	0	0
Estimate Fair Value Loss	(59)	(120)
Fair Value Hedges \| Matched interest rate swaps \| Accrued interest and other liabilities
Derivatives, Fair Value [Line Items]
Inerest-bearing deposit liability	653,301	546,458
Estimate Fair Value Gain	0	44
Estimate Fair Value Loss	(32,186)	(14,015)
Fair Value Hedges \| Matched interest rate swaps \| Accrued interest and other assets
Derivatives, Fair Value [Line Items]
Inerest-bearing deposit liability	653,301	546,458
Estimate Fair Value Gain	32,181	13,981
Estimate Fair Value Loss	$ 0	$ (44)

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
-Section 13
-Sentence Column B

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+ References

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-Name Accounting Standards Codification
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-Section 50
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+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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