FAIR VALUE - Assets and Liabilities Measured at Fair Value on a Recurring Basis (Details) - USD ($) $ in Thousands	Sep. 30, 2016	Dec. 31, 2015	Sep. 30, 2015
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial Assets	$ 1,025,048	$ 925,279
Transfers between Level 1 and Level 2
Transfers of assets from Level 1 to Level 2	0		$ 0
Transfers of assets from Level 2 to Level 1	0		$ 0
U. S. government agency
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial Assets	436	504
State and municipal
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial Assets	359,697	350,733
Mortgage-backed securities-residential (Government Sponsored Entity)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial Assets	456,464	334,080
Collateralized mortgage obligations (Government Sponsored Entity)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial Assets	195,619	228,749
Equity securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial Assets	6,233	4,689
Other securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial Assets	6,599	6,524
Recurring basis | Carrying Value
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial Assets	1,025,048	925,279
Mortgage banking derivatives	1,057	700
Fair value, assets	6,255	1,508
Derivative liability	(6,255)	(1,508)
Recurring basis | Quoted Prices in Active Markets for Identical Assets (Level 1) | Fair Value
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial Assets	6,233	4,689
Recurring basis | Significant Other Observable Inputs (Level 2) | Fair Value
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial Assets	1,001,962	903,208
Mortgage banking derivatives	1,057	700
Fair value, assets	6,255	1,508
Derivative liability	(6,255)	(1,508)
Recurring basis | Significant Unobservable Inputs (Level 3) | Fair Value
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial Assets	16,853	17,382
Recurring basis | U. S. government agency | Carrying Value
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial Assets	436	504
Recurring basis | U. S. government agency | Significant Other Observable Inputs (Level 2) | Fair Value
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial Assets	436	504
Recurring basis | State and municipal | Carrying Value
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial Assets	359,697	350,733
Recurring basis | State and municipal | Significant Other Observable Inputs (Level 2) | Fair Value
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial Assets	349,443	339,875
Recurring basis | State and municipal | Significant Unobservable Inputs (Level 3) | Fair Value
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial Assets	10,254	10,858
Recurring basis | Mortgage-backed securities-residential (Government Sponsored Entity) | Carrying Value
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial Assets	456,464	334,080
Recurring basis | Mortgage-backed securities-residential (Government Sponsored Entity) | Significant Other Observable Inputs (Level 2) | Fair Value
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial Assets	456,464	334,080
Recurring basis | Collateralized mortgage obligations (Government Sponsored Entity) | Carrying Value
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial Assets	195,619	228,749
Recurring basis | Collateralized mortgage obligations (Government Sponsored Entity) | Significant Other Observable Inputs (Level 2) | Fair Value
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial Assets	195,619	228,749
Recurring basis | Equity securities | Carrying Value
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial Assets	6,233	4,689
Recurring basis | Equity securities | Quoted Prices in Active Markets for Identical Assets (Level 1) | Fair Value
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial Assets	6,233	4,689
Recurring basis | Other securities | Carrying Value
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial Assets	6,599	6,524
Recurring basis | Other securities | Significant Unobservable Inputs (Level 3) | Fair Value
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial Assets	$ 6,599	$ 6,524