Disclosures of Fair Values of Financial Instruments (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2012	Dec. 31, 2011
Available-for-sale: [Abstract]
Total available-for-sale securities	$ 508,309	$ 478,916
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning balance	777	649
Transfers into Level 3	0	0
Transfers out of Level 3	(58)	0
Total gains or losses [Abstract]
Included in net income	127	(886)
Included in other comprehensive income (loss)	517	1,108
Purchases, issuances, sales and settlements [Abstract]
Purchases	0	0
Issuances	0	0
Sales	0	0
Settlements	(778)	(94)
Ending balance	585	777
Total gains or losses for the period included in net income attributable to the change in unrealized gains or losses related to assets and liabilities still held at the reporting date	0	886
Impaired Loans Receivable [Abstract]
Carrying amount of loans with a specific allowance		2,562
Fair value of loans with a specific allowance		2,282
Specific Allowance		280
Fair Value, Measurements, Recurring [Member]
Available-for-sale: [Abstract]
Total available-for-sale securities	508,309	478,916
Fair Value, Measurements, Recurring [Member] \| Quoted Prices in Active Markets for Identical Assets (Level 1)
Available-for-sale: [Abstract]
Total available-for-sale securities	60	29
Fair Value, Measurements, Recurring [Member] \| Significant Other Observable Inputs (Level 2)
Available-for-sale: [Abstract]
Total available-for-sale securities	507,664	478,110
Fair Value, Measurements, Recurring [Member] \| Significant Unobservable Inputs (Level 3)
Available-for-sale: [Abstract]
Total available-for-sale securities	585	777
Fair Value, Measurements, Nonrecurring [Member]
Impaired Loans Receivable [Abstract]
Carrying amount of loans with a specific allowance	3,192
Fair value of loans with a specific allowance	2,681
Specific Allowance	511
U.S. Treasury securities and obligations of U.S. government corporations & agencies
Available-for-sale: [Abstract]
Total available-for-sale securities	182,169	166,066
U.S. Treasury securities and obligations of U.S. government corporations & agencies \| Fair Value, Measurements, Recurring [Member]
Available-for-sale: [Abstract]
Total available-for-sale securities	182,169	166,066
U.S. Treasury securities and obligations of U.S. government corporations & agencies \| Fair Value, Measurements, Recurring [Member] \| Quoted Prices in Active Markets for Identical Assets (Level 1)
Available-for-sale: [Abstract]
Total available-for-sale securities	0	0
U.S. Treasury securities and obligations of U.S. government corporations & agencies \| Fair Value, Measurements, Recurring [Member] \| Significant Other Observable Inputs (Level 2)
Available-for-sale: [Abstract]
Total available-for-sale securities	182,169	166,066
U.S. Treasury securities and obligations of U.S. government corporations & agencies \| Fair Value, Measurements, Recurring [Member] \| Significant Unobservable Inputs (Level 3)
Available-for-sale: [Abstract]
Total available-for-sale securities	0	0
Obligations of states and political subdivisions
Available-for-sale: [Abstract]
Total available-for-sale securities	56,207	41,202
Obligations of states and political subdivisions \| Fair Value, Measurements, Recurring [Member]
Available-for-sale: [Abstract]
Total available-for-sale securities	56,207	41,202
Obligations of states and political subdivisions \| Fair Value, Measurements, Recurring [Member] \| Quoted Prices in Active Markets for Identical Assets (Level 1)
Available-for-sale: [Abstract]
Total available-for-sale securities	0	0
Obligations of states and political subdivisions \| Fair Value, Measurements, Recurring [Member] \| Significant Other Observable Inputs (Level 2)
Available-for-sale: [Abstract]
Total available-for-sale securities	56,207	41,202
Obligations of states and political subdivisions \| Fair Value, Measurements, Recurring [Member] \| Significant Unobservable Inputs (Level 3)
Available-for-sale: [Abstract]
Total available-for-sale securities	0	0
Mortgage-backed securities
Available-for-sale: [Abstract]
Total available-for-sale securities	259,460	261,833
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning balance	58	68
Transfers into Level 3	0	0
Transfers out of Level 3	(58)	0
Total gains or losses [Abstract]
Included in net income	0	0
Included in other comprehensive income (loss)	0	0
Purchases, issuances, sales and settlements [Abstract]
Purchases	0	0
Issuances	0	0
Sales	0	0
Settlements	0	(10)
Ending balance	0	58
Total gains or losses for the period included in net income attributable to the change in unrealized gains or losses related to assets and liabilities still held at the reporting date	0	0
Mortgage-backed securities \| Fair Value, Measurements, Recurring [Member]
Available-for-sale: [Abstract]
Total available-for-sale securities	259,460	261,833
Mortgage-backed securities \| Fair Value, Measurements, Recurring [Member] \| Quoted Prices in Active Markets for Identical Assets (Level 1)
Available-for-sale: [Abstract]
Total available-for-sale securities	0	0
Mortgage-backed securities \| Fair Value, Measurements, Recurring [Member] \| Significant Other Observable Inputs (Level 2)
Available-for-sale: [Abstract]
Total available-for-sale securities	259,460	261,775
Mortgage-backed securities \| Fair Value, Measurements, Recurring [Member] \| Significant Unobservable Inputs (Level 3)
Available-for-sale: [Abstract]
Total available-for-sale securities	0	58
Trust preferred securities
Available-for-sale: [Abstract]
Total available-for-sale securities	585	719
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning balance	719	581
Transfers into Level 3	0	0
Transfers out of Level 3	0	0
Total gains or losses [Abstract]
Included in net income	127	(886)
Included in other comprehensive income (loss)	517	1,108
Purchases, issuances, sales and settlements [Abstract]
Purchases	0	0
Issuances	0	0
Sales	0	0
Settlements	(778)	(84)
Ending balance	585	719
Total gains or losses for the period included in net income attributable to the change in unrealized gains or losses related to assets and liabilities still held at the reporting date	0	886
Trust preferred securities \| Fair Value, Measurements, Recurring [Member]
Available-for-sale: [Abstract]
Total available-for-sale securities	585	719
Trust preferred securities \| Fair Value, Measurements, Recurring [Member] \| Quoted Prices in Active Markets for Identical Assets (Level 1)
Available-for-sale: [Abstract]
Total available-for-sale securities	0	0
Trust preferred securities \| Fair Value, Measurements, Recurring [Member] \| Significant Other Observable Inputs (Level 2)
Available-for-sale: [Abstract]
Total available-for-sale securities	0	0
Trust preferred securities \| Fair Value, Measurements, Recurring [Member] \| Significant Unobservable Inputs (Level 3)
Available-for-sale: [Abstract]
Total available-for-sale securities	585	719
Other securities
Available-for-sale: [Abstract]
Total available-for-sale securities	9,888	9,096
Other securities \| Fair Value, Measurements, Recurring [Member]
Available-for-sale: [Abstract]
Total available-for-sale securities	9,888	9,096
Other securities \| Fair Value, Measurements, Recurring [Member] \| Quoted Prices in Active Markets for Identical Assets (Level 1)
Available-for-sale: [Abstract]
Total available-for-sale securities	60	29
Other securities \| Fair Value, Measurements, Recurring [Member] \| Significant Other Observable Inputs (Level 2)
Available-for-sale: [Abstract]
Total available-for-sale securities	9,828	9,067
Other securities \| Fair Value, Measurements, Recurring [Member] \| Significant Unobservable Inputs (Level 3)
Available-for-sale: [Abstract]
Total available-for-sale securities	$ 0	$ 0

Amount of allowance for credit losses related to recorded investment measured at fair value on a nonrecurring basis.

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Amount of investment in impaired financing receivables, for which there is a related allowance for credit losses, measured at fair value on a nonrecurring basis.

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Total of debt securities categorized neither as held-to-maturity nor trading which are intended be sold or mature within one year from the balance sheet date or the normal operating cycle, whichever is longer.

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Amount of gain (loss) recognized in earnings, arising from assets measured at fair value on a recurring basis using unobservable inputs (level 3).

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Amount of gain (loss) recognized in other comprehensive income, arising from assets measured at fair value on a recurring basis using unobservable inputs (level 3).

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Issues that have taken place during the period in relation to assets measured at fair value and categorized within Level 3 of the fair value hierarchy.

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Sales that have taken place during the period in relation to assets measured at fair value and categorized within Level 3 of the fair value hierarchy.

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Transfers into assets measured at fair value and categorized within Level 3 of the fair value hierarchy that have taken place during the period.

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This element represents an asset measured at fair value using significant unobservable inputs (Level 3) which is required for reconciliation purposes of beginning and ending balances.

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Net of tax amount of the income statement impact of the reclassification adjustment for unrealized (losses) realized upon the write-down of available-for-sale securities.

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