FAIR VALUE MEASUREMENT AND DISCLOSURE (Summary of Financial Assets and Liabilities Measured at Fair Value on Recurring Basis) (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Financial assets:
Loans held for sale	$ 8,711	$ 4,314
Available-for-sale Securities	924,311	910,692
Obligations of states and political subdivisions
Financial assets:
Available-for-sale Securities	93,020	93,752
Mortgage-backed securities issued or guaranteed by U.S. government-sponsored enterprises
Financial assets:
Available-for-sale Securities	448,821	453,672
Collateralized mortgage obligations issued or guaranteed by U.S. government-sponsored enterprises
Financial assets:
Available-for-sale Securities	361,400	342,894
Fair Value, Measurements, Recurring
Financial assets:
Loans held for sale	8,795	4,403
Customer loan swaps	7,722
Financial liabilities:
Junior subordinated debt interest rate swaps		5,682
Customer loan swaps	31
Fair Value, Measurements, Recurring \| Obligations of states and political subdivisions
Financial assets:
Available-for-sale Securities	93,020	93,752
Fair Value, Measurements, Recurring \| Mortgage-backed securities issued or guaranteed by U.S. government-sponsored enterprises
Financial assets:
Available-for-sale Securities	448,821	453,672
Fair Value, Measurements, Recurring \| Collateralized mortgage obligations issued or guaranteed by U.S. government-sponsored enterprises
Financial assets:
Available-for-sale Securities	361,400	342,894
Fair Value, Measurements, Recurring \| Corporate Bond Securities [Member]
Financial assets:
Available-for-sale Securities	21,070	20,374
Fair Value, Measurements, Recurring \| Equity investments
Financial assets:
Available-for-sale Securities	988	746
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 investments
Financial assets:
Available-for-sale Securities	0	0
Observable Market Data (Level 2) \| Fair Value, Measurements, Recurring
Financial assets:
Loans held for sale	8,795	4,403
Customer loan swaps	7,722
Financial liabilities:
Junior subordinated debt interest rate swaps		5,682
Customer loan swaps	31
Observable Market Data (Level 2) \| Fair Value, Measurements, Recurring \| Obligations of states and political subdivisions
Financial assets:
Available-for-sale Securities	93,020	93,752
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	448,821	453,672
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	361,400	342,894
Observable Market Data (Level 2) \| Fair Value, Measurements, Recurring \| Corporate Bond Securities [Member]
Financial assets:
Available-for-sale Securities	21,070	20,374
Observable Market Data (Level 2) \| Fair Value, Measurements, Recurring \| Equity investments
Financial assets:
Available-for-sale Securities	988	746
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 investments
Financial assets:
Available-for-sale Securities	0	0
Interest Rate Lock Commitments [Member] \| Fair Value, Measurements, Recurring
Financial assets:
Customer loan swaps	293	95
Financial liabilities:
Customer loan swaps	45	28
Interest Rate Lock Commitments [Member] \| Observable Market Data (Level 2) \| Fair Value, Measurements, Recurring
Financial assets:
Customer loan swaps	293	95
Financial liabilities:
Customer loan swaps	45	28
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	129	32
Financial liabilities:
Customer loan swaps		17
Forward Contracts [Member] \| Observable Market Data (Level 2) \| Fair Value, Measurements, Recurring
Financial assets:
Customer loan swaps	129	32
Financial liabilities:
Customer loan swaps		17
Interest rate swaps \| Fair Value, Measurements, Recurring
Financial assets:
Customer loan swaps		7,841
Financial liabilities:
Junior subordinated debt interest rate swaps	6,711
Customer loan swaps		7,841
Interest rate swaps \| Observable Market Data (Level 2) \| Fair Value, Measurements, Recurring
Financial assets:
Customer loan swaps		7,841
Financial liabilities:
Junior subordinated debt interest rate swaps	6,711
Customer loan swaps		7,841
Forward-Starting Interest Rate Swap \| Fair Value, Measurements, Recurring
Financial liabilities:
Junior subordinated debt interest rate swaps		30
Forward-Starting Interest Rate Swap \| Readily Available Market Prices (Level 1) \| Fair Value, Measurements, Recurring
Financial liabilities:
Junior subordinated debt interest rate swaps		0
Forward-Starting Interest Rate Swap \| Observable Market Data (Level 2) \| Fair Value, Measurements, Recurring
Financial liabilities:
Junior subordinated debt interest rate swaps		$ 30
Customer Loan Swaps \| Fair Value, Measurements, Recurring
Financial liabilities:
Customer loan swaps	7,722
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	7,722
Customer Loan Swaps \| Company Determined Fair Value (Level 3) \| Fair Value, Measurements, Recurring
Financial liabilities:
Customer loan swaps	$ 0

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