FAIR VALUE MEASUREMENT AND DISCLOSURE (Schedule of Carrying Amounts and Estimated Fair Value for Financial Instrument Assets and Liabilities) (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Financial assets:
Available-for-sale Securities	$ 780,343	$ 789,899
Held-to-maturity securities, at amortized cost	92,933	94,073
Held-to-maturity Securities, Fair Value	90,550	94,913
Mortgage servicing rights	1,856	1,766
Financial liabilities:
Time deposits	630,600	512,483
Short-term Debt, Fair Value	409,446	541,605
Long-term Debt, Fair Value	10,620	10,777
Subordinated debentures	50,465	44,333
Residential Real Estate
Financial assets:
Loans receivable, net of allowance	904,765	853,056
Commercial Real Estate
Financial assets:
Loans receivable, net of allowance	1,156,934	1,115,618
Commercial
Financial assets:
Loans receivable, net of allowance	394,903	401,902
Home Equity
Financial assets:
Loans receivable, net of allowance	315,453	318,230
Consumer
Financial assets:
Loans receivable, net of allowance	18,894	17,335
Readily Available Market Prices (Level 1)
Financial assets:
Held-to-maturity Securities, Fair Value	0	0
Mortgage servicing rights	0	0
Financial liabilities:
Time deposits	0	0
Short-term Debt, Fair Value	0	0
Long-term Debt, Fair Value	0	0
Subordinated debentures	0	0
Readily Available Market Prices (Level 1) \| Residential Real Estate
Financial assets:
Loans receivable, net of allowance	0	0
Readily Available Market Prices (Level 1) \| Commercial Real Estate
Financial assets:
Loans receivable, net of allowance	0	0
Readily Available Market Prices (Level 1) \| Commercial
Financial assets:
Loans receivable, net of allowance	0	0
Readily Available Market Prices (Level 1) \| Home Equity
Financial assets:
Loans receivable, net of allowance	0	0
Readily Available Market Prices (Level 1) \| Consumer
Financial assets:
Loans receivable, net of allowance	0	0
Observable Market Data (Level 2)
Financial assets:
Held-to-maturity Securities, Fair Value	90,550	94,913
Mortgage servicing rights	0	0
Financial liabilities:
Time deposits	630,600	512,483
Short-term Debt, Fair Value	409,446	541,605
Long-term Debt, Fair Value	10,620	10,777
Subordinated debentures	50,465	44,333
Observable Market Data (Level 2) \| Residential Real Estate
Financial assets:
Loans receivable, net of allowance	0	0
Observable Market Data (Level 2) \| Commercial Real Estate
Financial assets:
Loans receivable, net of allowance	0	0
Observable Market Data (Level 2) \| Commercial
Financial assets:
Loans receivable, net of allowance	0	0
Observable Market Data (Level 2) \| Home Equity
Financial assets:
Loans receivable, net of allowance	0	0
Observable Market Data (Level 2) \| Consumer
Financial assets:
Loans receivable, net of allowance	0	0
Company Determined Fair Value (Level 3)
Financial assets:
Held-to-maturity Securities, Fair Value	0	0
Mortgage servicing rights	1,856	1,766
Financial liabilities:
Time deposits	0	0
Short-term Debt, Fair Value	0	0
Long-term Debt, Fair Value	0	0
Subordinated debentures	0	0
Company Determined Fair Value (Level 3) \| Residential Real Estate
Financial assets:
Loans receivable, net of allowance	904,765	853,056
Company Determined Fair Value (Level 3) \| Commercial Real Estate
Financial assets:
Loans receivable, net of allowance	1,156,934	1,115,618
Company Determined Fair Value (Level 3) \| Commercial
Financial assets:
Loans receivable, net of allowance	394,903	401,902
Company Determined Fair Value (Level 3) \| Home Equity
Financial assets:
Loans receivable, net of allowance	315,453	318,230
Company Determined Fair Value (Level 3) \| Consumer
Financial assets:
Loans receivable, net of allowance	18,894	17,335
Carrying Amount
Financial assets:
Held-to-maturity securities, at amortized cost	92,933	94,073
Mortgage servicing rights	877	1,025
Financial liabilities:
Time deposits	638,418	517,032
Short-term Debt, Fair Value	409,732	541,796
Long-term Debt, Fair Value	10,738	10,791
Subordinated debentures	59,028	58,911
Carrying Amount \| Residential Real Estate
Financial assets:
Loans receivable, net of allowance	935,728	853,283
Carrying Amount \| Commercial Real Estate
Financial assets:
Loans receivable, net of allowance	1,205,397	1,152,160
Carrying Amount \| Commercial
Financial assets:
Loans receivable, net of allowance	401,330	413,898
Carrying Amount \| Home Equity
Financial assets:
Loans receivable, net of allowance	322,877	321,011
Carrying Amount \| Consumer
Financial assets:
Loans receivable, net of allowance	$ 19,985	$ 17,916

Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
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Amount after other than temporary impairment (OTTI) accretion, of investments in debt securities classified as held-to-maturity.

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Fair value of investments in debt securities classified as held-to-maturity.

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