FAIR VALUE MEASUREMENT AND DISCLOSURE (Summary of Financial Assets and Liabilities Measured at Fair Value on Recurring Basis) (Details) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Financial assets:
Available-for-sale Securities	$ 796,687	$ 789,899
Obligations of states and political subdivisions
Financial assets:
Available-for-sale Securities	5,827	7,335
Mortgage-backed securities issued or guaranteed by U.S. government-sponsored enterprises
Financial assets:
Available-for-sale Securities	502,996	503,302
Collateralized mortgage obligations issued or guaranteed by U.S. government-sponsored enterprises
Financial assets:
Available-for-sale Securities	282,279	272,799
Equity Securities [Member]
Financial assets:
Available-for-sale Securities		806
Fair Value, Measurements, Recurring
Financial assets:
Loans held for sale	9,548	8,103
Customer loan swaps	10,707
Financial liabilities:
Junior subordinated debt interest rate swaps		7,571
Customer loan swaps	22
Fair Value, Measurements, Recurring \| Obligations of states and political subdivisions
Financial assets:
Available-for-sale Securities	5,827	7,335
Fair Value, Measurements, Recurring \| Mortgage-backed securities issued or guaranteed by U.S. government-sponsored enterprises
Financial assets:
Available-for-sale Securities	502,996	503,302
Fair Value, Measurements, Recurring \| Collateralized mortgage obligations issued or guaranteed by U.S. government-sponsored enterprises
Financial assets:
Available-for-sale Securities	282,279	272,799
Fair Value, Measurements, Recurring \| Corporate Bond Securities [Member]
Financial assets:
Available-for-sale Securities	5,585	5,657
Fair Value, Measurements, Recurring \| Equity Securities [Member]
Financial assets:
Available-for-sale Securities	761	806
Readily Available Market Prices (Level 1) \| Fair Value, Measurements, Recurring
Financial assets:
Loans held for sale	0	0
Readily Available Market Prices (Level 1) \| Fair Value, Measurements, Recurring \| Corporate Bond Securities [Member]
Financial assets:
Available-for-sale Securities	0	0
Readily Available Market Prices (Level 1) \| Fair Value, Measurements, Recurring \| Equity Securities [Member]
Financial assets:
Available-for-sale Securities	0	0
Observable Market Data (Level 2) \| Fair Value, Measurements, Recurring
Financial assets:
Loans held for sale	9,548	8,103
Customer loan swaps	10,707
Financial liabilities:
Junior subordinated debt interest rate swaps		7,571
Customer loan swaps	22
Observable Market Data (Level 2) \| Fair Value, Measurements, Recurring \| Obligations of states and political subdivisions
Financial assets:
Available-for-sale Securities	5,827	7,335
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	502,996	503,302
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	282,279	272,799
Observable Market Data (Level 2) \| Fair Value, Measurements, Recurring \| Corporate Bond Securities [Member]
Financial assets:
Available-for-sale Securities	5,585	5,657
Observable Market Data (Level 2) \| Fair Value, Measurements, Recurring \| Equity Securities [Member]
Financial assets:
Available-for-sale Securities	761	806
Company Determined Fair Value (Level 3) \| Fair Value, Measurements, Recurring
Financial assets:
Loans held for sale	0	0
Company Determined Fair Value (Level 3) \| Fair Value, Measurements, Recurring \| Corporate Bond Securities [Member]
Financial assets:
Available-for-sale Securities	0	0
Company Determined Fair Value (Level 3) \| Fair Value, Measurements, Recurring \| Equity Securities [Member]
Financial assets:
Available-for-sale Securities	0	0
Interest Rate Lock Commitments [Member] \| Fair Value, Measurements, Recurring
Financial assets:
Customer loan swaps	308	307
Financial liabilities:
Customer loan swaps	35	22
Interest Rate Lock Commitments [Member] \| Observable Market Data (Level 2) \| Fair Value, Measurements, Recurring
Financial assets:
Customer loan swaps	308	307
Financial liabilities:
Customer loan swaps	35	22
Interest Rate Lock Commitments [Member] \| Company Determined Fair Value (Level 3) \| Fair Value, Measurements, Recurring
Financial liabilities:
Customer loan swaps	0	0
Forward Contracts [Member] \| Fair Value, Measurements, Recurring
Financial assets:
Customer loan swaps	145	158
Financial liabilities:
Customer loan swaps		16
Forward Contracts [Member] \| Observable Market Data (Level 2) \| Fair Value, Measurements, Recurring
Financial assets:
Customer loan swaps	145	158
Financial liabilities:
Customer loan swaps		16
Interest rate swaps \| Fair Value, Measurements, Recurring
Financial assets:
Customer loan swaps		5,036
Financial liabilities:
Junior subordinated debt interest rate swaps	5,877
Customer loan swaps		5,036
Interest rate swaps \| Observable Market Data (Level 2) \| Fair Value, Measurements, Recurring
Financial assets:
Customer loan swaps		5,036
Financial liabilities:
Junior subordinated debt interest rate swaps	5,877
Customer loan swaps		5,036
Forward-Starting Interest Rate Swap \| Fair Value, Measurements, Recurring
Financial liabilities:
Junior subordinated debt interest rate swaps	85	21
Forward-Starting Interest Rate Swap \| Readily Available Market Prices (Level 1) \| Fair Value, Measurements, Recurring
Financial liabilities:
Junior subordinated debt interest rate swaps	0	0
Forward-Starting Interest Rate Swap \| Observable Market Data (Level 2) \| Fair Value, Measurements, Recurring
Financial liabilities:
Junior subordinated debt interest rate swaps	85	$ 21
Forward-Starting Interest Rate Swap \| Company Determined Fair Value (Level 3) \| Fair Value, Measurements, Recurring
Financial liabilities:
Junior subordinated debt interest rate swaps	0
Customer Loan Swaps \| Fair Value, Measurements, Recurring
Financial liabilities:
Customer loan swaps	10,707
Customer Loan Swaps \| Readily Available Market Prices (Level 1) \| Fair Value, Measurements, Recurring
Financial liabilities:
Customer loan swaps	0
Customer Loan Swaps \| Observable Market Data (Level 2) \| Fair Value, Measurements, Recurring
Financial liabilities:
Customer loan swaps	10,707
Customer Loan Swaps \| Company Determined Fair Value (Level 3) \| Fair Value, Measurements, Recurring
Financial liabilities:
Customer loan swaps	$ 0

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