FAIR VALUE MEASUREMENT (Summary of Financial Assets and Liabilities Measured at Fair Value on Recurring Basis) (Details) - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014
Financial assets:
Loans held for sale	$ 890
Available-for-sale Securities	724,237	$ 763,063
Customer interest rate swap agreements	3,188	1,140
Financial liabilities:
Customer interest rate swap agreements	3,188	1,140
Obligations of U.S. government-sponsored enterprises
Financial assets:
Available-for-sale Securities	5,094	5,027
Obligations of states and political subdivisions
Financial assets:
Available-for-sale Securities	19,872	26,777
Mortgage-backed securities issued or guaranteed by U.S. government-sponsored enterprises
Financial assets:
Available-for-sale Securities	381,049	381,308
Collateralized mortgage obligations issued or guaranteed by U.S. government-sponsored enterprises
Financial assets:
Available-for-sale Securities	318,222	343,897
Private issue collateralized mortgage obligations
Financial assets:
Available-for-sale Securities		6,054
Fair Value, Measurements, Recurring
Financial assets:
Loans held for sale	890
Customer interest rate swap agreements	3,188	1,140
Financial liabilities:
Interest rate swap agreements		9,143
Customer interest rate swap agreements	3,188	1,140
Fair Value, Measurements, Recurring \| Obligations of U.S. government-sponsored enterprises
Financial assets:
Available-for-sale Securities	5,094	5,027
Fair Value, Measurements, Recurring \| Obligations of states and political subdivisions
Financial assets:
Available-for-sale Securities	19,872	26,777
Fair Value, Measurements, Recurring \| Mortgage-backed securities issued or guaranteed by U.S. government-sponsored enterprises
Financial assets:
Available-for-sale Securities	381,049	381,308
Fair Value, Measurements, Recurring \| Collateralized mortgage obligations issued or guaranteed by U.S. government-sponsored enterprises
Financial assets:
Available-for-sale Securities	318,222	343,897
Fair Value, Measurements, Recurring \| Private issue collateralized mortgage obligations
Financial assets:
Available-for-sale Securities		6,054
Readily Available Market Prices (Level 1)
Financial assets:
Loans held for sale	0
Available-for-sale Securities	0	0
Customer interest rate swap agreements	0	0
Financial liabilities:
Customer interest rate swap agreements	0	0
Readily Available Market Prices (Level 1) \| Fair Value, Measurements, Recurring
Financial assets:
Loans held for sale	0
Financial liabilities:
Customer interest rate swap agreements	0	0
Observable Market Data (Level 2)
Financial assets:
Loans held for sale	890
Available-for-sale Securities	724,237	763,063
Customer interest rate swap agreements	3,188	1,140
Financial liabilities:
Customer interest rate swap agreements	3,188	1,140
Observable Market Data (Level 2) \| Fair Value, Measurements, Recurring
Financial assets:
Loans held for sale	890
Customer interest rate swap agreements	3,188	1,140
Financial liabilities:
Interest rate swap agreements		9,143
Customer interest rate swap agreements	3,188	1,140
Observable Market Data (Level 2) \| Fair Value, Measurements, Recurring \| Obligations of U.S. government-sponsored enterprises
Financial assets:
Available-for-sale Securities	5,094	5,027
Observable Market Data (Level 2) \| Fair Value, Measurements, Recurring \| Obligations of states and political subdivisions
Financial assets:
Available-for-sale Securities	19,872	26,777
Observable Market Data (Level 2) \| Fair Value, Measurements, Recurring \| Mortgage-backed securities issued or guaranteed by U.S. government-sponsored enterprises
Financial assets:
Available-for-sale Securities	381,049	381,308
Observable Market Data (Level 2) \| Fair Value, Measurements, Recurring \| Collateralized mortgage obligations issued or guaranteed by U.S. government-sponsored enterprises
Financial assets:
Available-for-sale Securities	318,222	343,897
Observable Market Data (Level 2) \| Fair Value, Measurements, Recurring \| Private issue collateralized mortgage obligations
Financial assets:
Available-for-sale Securities		6,054
Company Determined Fair Value (Level 3)
Financial assets:
Loans held for sale	0
Available-for-sale Securities	0	0
Customer interest rate swap agreements	0	0
Financial liabilities:
Customer interest rate swap agreements	0	0
Company Determined Fair Value (Level 3) \| Fair Value, Measurements, Recurring
Financial assets:
Loans held for sale	0
Financial liabilities:
Customer interest rate swap agreements	0	0
Interest rate swaps
Financial liabilities:
Interest rate swap agreements	10,165	9,143
Interest rate swaps \| Fair Value, Measurements, Recurring
Financial liabilities:
Interest rate swap agreements	10,165
Interest rate swaps \| Readily Available Market Prices (Level 1)
Financial liabilities:
Interest rate swap agreements	0	0
Interest rate swaps \| Observable Market Data (Level 2)
Financial liabilities:
Interest rate swap agreements	10,165	9,143
Interest rate swaps \| Observable Market Data (Level 2) \| Fair Value, Measurements, Recurring
Financial liabilities:
Interest rate swap agreements	10,165
Interest rate swaps \| Company Determined Fair Value (Level 3)
Financial liabilities:
Interest rate swap agreements	0	$ 0
Forward-Starting Interest Rate Swap
Financial liabilities:
Interest rate swap agreements	887
Forward-Starting Interest Rate Swap \| Fair Value, Measurements, Recurring
Financial liabilities:
Interest rate swap agreements	887
Forward-Starting Interest Rate Swap \| Readily Available Market Prices (Level 1)
Financial liabilities:
Interest rate swap agreements	0
Forward-Starting Interest Rate Swap \| Readily Available Market Prices (Level 1) \| Fair Value, Measurements, Recurring
Financial liabilities:
Interest rate swap agreements	0
Forward-Starting Interest Rate Swap \| Observable Market Data (Level 2)
Financial liabilities:
Interest rate swap agreements	887
Forward-Starting Interest Rate Swap \| Observable Market Data (Level 2) \| Fair Value, Measurements, Recurring
Financial liabilities:
Interest rate swap agreements	887
Forward-Starting Interest Rate Swap \| Company Determined Fair Value (Level 3)
Financial liabilities:
Interest rate swap agreements	0
Forward-Starting Interest Rate Swap \| Company Determined Fair Value (Level 3) \| Fair Value, Measurements, Recurring
Financial liabilities:
Interest rate swap agreements	$ 0

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