FAIR VALUE MEASUREMENT (Schedule of Carrying Amounts and Estimated Fair Value for Financial Instrument Assets and Liabilities) (Details) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2013	Dec. 31, 2012
Financial assets:
Loans held for sale	$ 1,608
Readily Available Market Prices (Level 1)
Financial assets:
Cash and due from banks	46,868	58,290
Securities available for sale
FHLB and Federal Reserve Bank stock	19,724	21,034
Trading account assets	2,244	2,300
Loans held for sale
Loans receivable, net of allowance
Mortgage servicing rights
Interest receivable
Investment in trust preferred securities affiliates
Customer interest rate swap agreements
Financial liabilities:
Deposits	1,313,574	1,339,290
FHLB advances
Commercial repurchase agreements
Other borrowed funds	190,916	193,753
Junior subordinated debentures
Interest payable	616	905
Interest rate swap agreements
Readily Available Market Prices (Level 1) \| Residential real estate loans
Financial assets:
Loans receivable, net of allowance
Readily Available Market Prices (Level 1) \| Commercial real estate loans
Financial assets:
Loans receivable, net of allowance
Readily Available Market Prices (Level 1) \| Commercial loans
Financial assets:
Loans receivable, net of allowance
Readily Available Market Prices (Level 1) \| Home equity loans
Financial assets:
Loans receivable, net of allowance
Readily Available Market Prices (Level 1) \| Consumer loans
Financial assets:
Loans receivable, net of allowance
Observable Market Data (Level 2)
Financial assets:
Cash and due from banks
Securities available for sale	803,620	781,050
FHLB and Federal Reserve Bank stock
Trading account assets
Loans held for sale	1,608
Loans receivable, net of allowance
Mortgage servicing rights	1,373	879
Interest receivable	6,660	6,215
Investment in trust preferred securities affiliates
Customer interest rate swap agreements	449	496
Financial liabilities:
Deposits	646,135	597,156
FHLB advances	105,354	60,813
Commercial repurchase agreements	32,788	69,067
Other borrowed funds
Junior subordinated debentures	43,845	43,819
Interest payable
Interest rate swap agreements	10,225	11,580
Observable Market Data (Level 2) \| Residential real estate loans
Financial assets:
Loans receivable, net of allowance
Observable Market Data (Level 2) \| Commercial real estate loans
Financial assets:
Loans receivable, net of allowance
Observable Market Data (Level 2) \| Commercial loans
Financial assets:
Loans receivable, net of allowance
Observable Market Data (Level 2) \| Home equity loans
Financial assets:
Loans receivable, net of allowance
Observable Market Data (Level 2) \| Consumer loans
Financial assets:
Loans receivable, net of allowance
Company Determined Fair Value (Level 3)
Financial assets:
Cash and due from banks
Securities available for sale
FHLB and Federal Reserve Bank stock
Trading account assets
Loans held for sale
Mortgage servicing rights
Interest receivable
Investment in trust preferred securities affiliates	1,331	1,331
Customer interest rate swap agreements
Financial liabilities:
Deposits
FHLB advances
Commercial repurchase agreements
Other borrowed funds
Junior subordinated debentures
Interest payable
Interest rate swap agreements
Company Determined Fair Value (Level 3) \| Residential real estate loans
Financial assets:
Loans receivable, net of allowance	585,656	591,139
Company Determined Fair Value (Level 3) \| Commercial real estate loans
Financial assets:
Loans receivable, net of allowance	492,105	492,602
Company Determined Fair Value (Level 3) \| Commercial loans
Financial assets:
Loans receivable, net of allowance	181,072	179,519
Company Determined Fair Value (Level 3) \| Home equity loans
Financial assets:
Loans receivable, net of allowance	288,867	277,194
Company Determined Fair Value (Level 3) \| Consumer loans
Financial assets:
Loans receivable, net of allowance	17,391	16,866
Carrying Amount
Financial assets:
Cash and due from banks	46,868	58,290
Securities available for sale	803,602	781,050
FHLB and Federal Reserve Bank stock	19,724	21,034
Trading account assets	2,244	2,300
Loans held for sale	1,608
Loans receivable, net of allowance		1,540,822
Mortgage servicing rights	671	542
Interest receivable	6,660	6,215
Investment in trust preferred securities affiliates	1,331	1,331
Customer interest rate swap agreements	449	496
Financial liabilities:
Deposits	1,951,785	1,929,469
FHLB advances	101,282	56,404
Commercial repurchase agreements	30,176	66,187
Other borrowed funds	190,916	193,753
Junior subordinated debentures	43,845	43,819
Interest payable	616	905
Interest rate swap agreements	10,225	11,580
Carrying Amount \| Residential real estate loans
Financial assets:
Loans receivable, net of allowance	563,708	564,184
Carrying Amount \| Commercial real estate loans
Financial assets:
Loans receivable, net of allowance	501,916	501,037
Carrying Amount \| Commercial loans
Financial assets:
Loans receivable, net of allowance	184,276	183,680
Carrying Amount \| Home equity loans
Financial assets:
Loans receivable, net of allowance	287,890	275,498
Carrying Amount \| Consumer loans
Financial assets:
Loans receivable, net of allowance	17,008	16,423
Fair Value
Financial assets:
Cash and due from banks	46,868	58,290
Securities available for sale	803,620	781,050
FHLB and Federal Reserve Bank stock	19,724	21,034
Trading account assets	2,244	2,300
Loans held for sale	1,608
Loans receivable, net of allowance		1,557,320
Mortgage servicing rights	1,373	879
Interest receivable	6,660	6,215
Investment in trust preferred securities affiliates	1,331	1,331
Customer interest rate swap agreements	449	496
Financial liabilities:
Deposits	1,959,709	1,936,446
FHLB advances	105,354	60,813
Commercial repurchase agreements	32,788	69,067
Other borrowed funds	190,916	193,753
Junior subordinated debentures	43,845	43,819
Interest payable	616	905
Interest rate swap agreements	10,225	11,580
Fair Value \| Residential real estate loans
Financial assets:
Loans receivable, net of allowance	585,656	591,139
Fair Value \| Commercial real estate loans
Financial assets:
Loans receivable, net of allowance	492,105	492,602
Fair Value \| Commercial loans
Financial assets:
Loans receivable, net of allowance	181,072	179,519
Fair Value \| Home equity loans
Financial assets:
Loans receivable, net of allowance	288,867	277,194
Fair Value \| Consumer loans
Financial assets:
Loans receivable, net of allowance	$ 17,391	$ 16,866

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Derivative instrument obligations meeting the definition of a liability which the Company is a party to as of the balance sheet date.

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