FAIR VALUE MEASUREMENT AND DISCLOSURE (Schedule of Carrying Amounts and Estimated Fair Value for Financial Instrument Assets and Liabilities) (Details) - USD ($) $ in Thousands		Mar. 31, 2019	Dec. 31, 2018
Financial assets:
Available-for-sale Securities		$ 924,311	$ 910,692
Held-to-maturity securities, at amortized cost		1,306	1,307
Held-to-maturity Securities, Fair Value		1,324	1,291
Loans held for sale		8,711	4,314
Mortgage servicing rights		1,540	1,677
Financial liabilities:
Time deposits		691,689	654,954
Short-term Debt, Fair Value		255,899	270,598
Long-term Debt, Fair Value		9,926	11,573
Subordinated debentures		49,578	49,060
Residential Real Estate
Financial assets:
Loans receivable, net of allowance	[1]	990,279	957,957
Commercial Real Estate
Financial assets:
Loans receivable, net of allowance	[1]	1,226,222	1,218,436
Commercial
Financial assets:
Loans receivable, net of allowance	[1],[2]	411,935	404,805
Home Equity
Financial assets:
Loans receivable, net of allowance	[1]	314,250	317,359
Consumer
Financial assets:
Loans receivable, net of allowance	[1]	18,918	18,969
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		1,324	1,291
Mortgage servicing rights		0	0
Financial liabilities:
Time deposits		691,689	654,954
Short-term Debt, Fair Value		255,899	270,598
Long-term Debt, Fair Value		9,926	11,573
Subordinated debentures		49,578	49,060
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		1,540	1,677
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	[1]	990,279	957,957
Company Determined Fair Value (Level 3) | Commercial Real Estate
Financial assets:
Loans receivable, net of allowance	[1]	1,226,222	1,218,436
Company Determined Fair Value (Level 3) | Commercial
Financial assets:
Loans receivable, net of allowance	[1],[2]	411,935	404,805
Company Determined Fair Value (Level 3) | Home Equity
Financial assets:
Loans receivable, net of allowance	[1]	314,250	317,359
Company Determined Fair Value (Level 3) | Consumer
Financial assets:
Loans receivable, net of allowance	[1]	18,918	18,969
Carrying Amount
Financial assets:
Held-to-maturity securities, at amortized cost		1,306	1,307
Mortgage servicing rights		772	831
Financial liabilities:
Time deposits		695,856	661,281
Short-term Debt, Fair Value		256,181	270,868
Long-term Debt, Fair Value		10,000	11,580
Subordinated debentures		58,978	59,067
Carrying Amount | Residential Real Estate
Financial assets:
Loans receivable, net of allowance	[1]	1,011,289	986,795
Carrying Amount | Commercial Real Estate
Financial assets:
Loans receivable, net of allowance	[1]	1,246,636	1,257,879
Carrying Amount | Commercial
Financial assets:
Loans receivable, net of allowance	[1],[2]	417,900	411,479
Carrying Amount | Home Equity
Financial assets:
Loans receivable, net of allowance	[1]	320,942	324,967
Carrying Amount | Consumer
Financial assets:
Loans receivable, net of allowance	[1]	$ 20,474	$ 20,390

[1] (1)The presented carrying amount is net of the allocated ALL.

[2] (2)Includes the HPFC loan portfolio.