FAIR VALUE MEASUREMENT (Schedule of Carrying Amounts and Estimated Fair Value for Financial Instrument Assets and Liabilities) (Details) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2013	Dec. 31, 2012
Financial assets:
Loans held for sale	$ 2,826
Readily Available Market Prices (Level 1)
Financial assets:
Cash and due from banks	44,896	58,290
FHLB and Federal Reserve Bank stock	19,724	21,034
Trading account assets	2,281	2,300
Financial liabilities:
Deposits	1,340,252	1,339,290
Other borrowed funds	188,153	193,753
Interest payable	563	905
Observable Market Data (Level 2)
Financial assets:
Securities available for sale	789,369	781,050
Loans held for sale	2,826
Mortgage servicing rights	1,316	879
Interest receivable	6,506	6,215
Customer interest rate swap agreements	193	496
Financial liabilities:
Deposits	559,094	597,156
FHLB advances	189,421	60,813
Commercial repurchase agreements	32,615	69,067
Junior subordinated debentures	43,845	43,819
Interest rate swap agreements	6,437	11,580
Company Determined Fair Value (Level 3)
Financial assets:
Investment in trust preferred securities affiliates	1,331	1,331
Company Determined Fair Value (Level 3) \| Residential real estate loans
Financial assets:
Loans receivable, net of allowance	575,594	591,139
Company Determined Fair Value (Level 3) \| Commercial real estate loans
Financial assets:
Loans receivable, net of allowance	508,194	492,602
Company Determined Fair Value (Level 3) \| Commercial loans
Financial assets:
Loans receivable, net of allowance	180,642	179,519
Company Determined Fair Value (Level 3) \| Home equity loans
Financial assets:
Loans receivable, net of allowance	296,968	277,194
Company Determined Fair Value (Level 3) \| Consumer loans
Financial assets:
Loans receivable, net of allowance	18,104	16,866
Carrying Amount
Financial assets:
Cash and due from banks	44,896	58,290
Securities available for sale	789,369	781,050
FHLB and Federal Reserve Bank stock	19,724	21,034
Trading account assets	2,281	2,300
Loans held for sale	2,826
Mortgage servicing rights	774	542
Interest receivable	6,506	6,215
Investment in trust preferred securities affiliates	1,331	1,331
Customer interest rate swap agreements	193	496
Financial liabilities:
Deposits	1,894,087	1,929,469
FHLB advances	186,147	56,404
Commercial repurchase agreements	30,165	66,187
Other borrowed funds	188,153	193,753
Junior subordinated debentures	43,870	43,819
Interest payable	563	905
Interest rate swap agreements	6,437	11,580
Carrying Amount \| Residential real estate loans
Financial assets:
Loans receivable, net of allowance	561,975	564,184
Carrying Amount \| Commercial real estate loans
Financial assets:
Loans receivable, net of allowance	518,640	501,037
Carrying Amount \| Commercial loans
Financial assets:
Loans receivable, net of allowance	183,059	183,680
Carrying Amount \| Home equity loans
Financial assets:
Loans receivable, net of allowance	297,717	275,498
Carrying Amount \| Consumer loans
Financial assets:
Loans receivable, net of allowance	17,847	16,423
Fair Value
Financial assets:
Cash and due from banks	44,896	58,290
Securities available for sale	789,369	781,050
FHLB and Federal Reserve Bank stock	19,724	21,034
Trading account assets	2,281	2,300
Loans held for sale	2,826
Mortgage servicing rights	1,316	879
Interest receivable	6,506	6,215
Investment in trust preferred securities affiliates	1,331	1,331
Customer interest rate swap agreements	193	496
Financial liabilities:
Deposits	1,899,346	1,936,446
FHLB advances	189,421	60,813
Commercial repurchase agreements	32,615	69,067
Other borrowed funds	188,153	193,753
Junior subordinated debentures	43,845	43,819
Interest payable	563	905
Interest rate swap agreements	6,437	11,580
Fair Value \| Residential real estate loans
Financial assets:
Loans receivable, net of allowance	575,594	591,139
Fair Value \| Commercial real estate loans
Financial assets:
Loans receivable, net of allowance	508,194	492,602
Fair Value \| Commercial loans
Financial assets:
Loans receivable, net of allowance	180,642	179,519
Fair Value \| Home equity loans
Financial assets:
Loans receivable, net of allowance	296,968	277,194
Fair Value \| Consumer loans
Financial assets:
Loans receivable, net of allowance	$ 18,104	$ 16,866

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