FAIR VALUE - Summary of Carrying Value and Fair Value of Company's Financial Instruments (Details) - USD ($) $ in Thousands		Jun. 30, 2015	Dec. 31, 2014
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities held to maturity		$ 214,777	$ 207,904
Loans, net		1,918,608	1,804,814
Quoted Prices in Active Markets for Identical Assets Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities held to maturity	[1]	0	0
Loans, net		0	0
Deposit liabilities		0	0
Borrowings		0	0
Subordinated debt		0	0
Significant Other Observable Inputs Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities held to maturity	[1]	216,176	208,788
Loans, net		0	0
Deposit liabilities		0	0
Borrowings		52,424	53,584
Subordinated debt		53,948	53,861
Significant Unobservable Inputs Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities held to maturity	[1]	0	0
Loans, net		1,926,219	1,814,746
Deposit liabilities		2,605,883	2,417,355
Borrowings		0	0
Subordinated debt		0	0
Carrying Amount [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities held to maturity	[1]	214,777	207,904
Loans, net		1,910,695	1,794,405
Deposit liabilities		2,605,177	2,416,534
Borrowings		50,000	50,000
Subordinated debt		$ 64,670	$ 64,583

[1] See Note D for further detail of fair value of individual investment categories.