DERIVATIVES - Additional Information (Details) $ in Thousands	9 Months Ended
	Sep. 30, 2015 USD ($) entity	Dec. 31, 2014 USD ($) entity
Derivative [Line Items]
Maximum derivative notional position as a percentage of assets	35.00%
Maximum credit exposure as a percentage of capital	3.00%
Maximum single counterparty credit risk exposure	$ 20,000
Inerest-bearing deposit liability	$ 1,050,781	$ 823,585
Number of counterparties | entity	7	9
Derivative Financial Instruments, Liabilities, Fair Value Disclosure	$ 18,836	$ 11,916
Interest Rate Cash Flow Hedge Asset at Fair Value		(1,700)
Cash Flow Hedging [Member]
Derivative [Line Items]
Inerest-bearing deposit liability		150,000
Credit Risk Contract [Member]
Derivative [Line Items]
Inerest-bearing deposit liability	31,000	26,400
Outstanding liability from counterparty contracts	100	100
Interest Rate Lock Commitments [Member]
Derivative [Line Items]
Inerest-bearing deposit liability	29,000
Other Credit Derivatives [Member]
Derivative [Line Items]
Inerest-bearing deposit liability	60,300
Outstanding liability from counterparty contracts	300
Accrued interest and other liabilities | Derivative [Member]
Derivative [Line Items]
Inerest-bearing deposit liability	528,500	566,200
Derivative Financial Instruments, Liabilities, Fair Value Disclosure	$ 18,300	$ 12,400