Allowance for Loan Losses (Details 2) (USD $) In Thousands, unless otherwise specified	3 Months Ended	9 Months Ended
Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012	Sep. 30, 2011
Allowance for loan losses:
Allowance for loan losses, beginning of period	$ 17,979	$ 15,915	$ 16,574	$ 14,053
Loans charged off	(728)	(1,283)	(1,787)	(2,252)
Recoveries	157	170	621	601
Provision	1,250	1,200	3,250	3,600
Allowance for loan losses, end of period	18,658	16,002	18,658	16,002
Amount of allowance for loan losses for loans deemed to be impaired			2,113	925
Amount of allowance for loan losses for loans not deemed to be impaired			16,545	15,077
Loans:
Ending balance	1,064,923	951,307	1,064,923	951,307
Loans deemed to be impaired	6,558	8,308	6,558	8,308
Loans not deemed to be impaired	1,058,365	942,999	1,058,365	942,999
Construction and Land Development [Member]
Allowance for loan losses:
Allowance for loan losses, beginning of period	2,889	2,572	2,893	1,752
Loans charged off		(900)		(900)
Recoveries
Provision	140	1,312	136	2,132
Allowance for loan losses, end of period	3,029	2,984	3,029	2,984
Amount of allowance for loan losses for loans deemed to be impaired			1,000	350
Amount of allowance for loan losses for loans not deemed to be impaired			2,029	2,634
Loans:
Ending balance	38,318	54,498	38,318	54,498
Loans deemed to be impaired	1,500	1,800	1,500	1,800
Loans not deemed to be impaired	36,818	52,698	36,818	52,698
Commercial and Industrial [Member]
Allowance for loan losses:
Allowance for loan losses, beginning of period	3,466	3,575	3,139	3,163
Loans charged off	(532)	(203)	(931)	(585)
Recoveries	38	66	243	222
Provision	133	(217)	654	421
Allowance for loan losses, end of period	3,105	3,221	3,105	3,221
Amount of allowance for loan losses for loans deemed to be impaired			455	345
Amount of allowance for loan losses for loans not deemed to be impaired			2,650	2,876
Loans:
Ending balance	78,567	84,765	78,567	84,765
Loans deemed to be impaired	1,882	1,778	1,882	1,778
Loans not deemed to be impaired	76,685	82,987	76,685	82,987
Commercial Real Estate [Member]
Allowance for loan losses:
Allowance for loan losses, beginning of period	7,754	6,321	6,566	5,671
Loans charged off
Recoveries	2		5
Provision	967	(364)	2,152	286
Allowance for loan losses, end of period	8,723	5,957	8,723	5,957
Amount of allowance for loan losses for loans deemed to be impaired			434	227
Amount of allowance for loan losses for loans not deemed to be impaired			8,289	5,730
Loans:
Ending balance	562,252	458,858	562,252	458,858
Loans deemed to be impaired	2,302	4,247	2,302	4,247
Loans not deemed to be impaired	559,950	454,611	559,950	454,611
Residential Real Estate [Member]
Allowance for loan losses:
Allowance for loan losses, beginning of period	1,793	1,745	1,886	1,718
Loans charged off	(49)		(110)	(281)
Recoveries	2	4	11	19
Provision	240	31	199	324
Allowance for loan losses, end of period	1,986	1,780	1,986	1,780
Amount of allowance for loan losses for loans deemed to be impaired			127	3
Amount of allowance for loan losses for loans not deemed to be impaired			1,859	1,777
Loans:
Ending balance	262,426	235,636	262,426	235,636
Loans deemed to be impaired	777	483	777	483
Loans not deemed to be impaired	261,649	235,153	261,649	235,153
Consumer [Member]
Allowance for loan losses:
Allowance for loan losses, beginning of period	293	291	356	298
Loans charged off	(147)	(180)	(587)	(485)
Recoveries	99	100	346	360
Provision	52	81	182	119
Allowance for loan losses, end of period	297	292	297	292
Amount of allowance for loan losses for loans deemed to be impaired
Amount of allowance for loan losses for loans not deemed to be impaired			297	292
Loans:
Ending balance	6,661	6,419	6,661	6,419
Loans deemed to be impaired
Loans not deemed to be impaired	6,661	6,419	6,661	6,419
Home Equity [Member]
Allowance for loan losses:
Allowance for loan losses, beginning of period	681	775	704	725
Loans charged off			(159)	(1)
Recoveries	16		16
Provision	176	8	312	59
Allowance for loan losses, end of period	873	783	873	783
Amount of allowance for loan losses for loans deemed to be impaired			97
Amount of allowance for loan losses for loans not deemed to be impaired			776	783
Loans:
Ending balance	116,699	111,131	116,699	111,131
Loans deemed to be impaired	97		97
Loans not deemed to be impaired	116,602	111,131	116,602	111,131
Unallocated [Member]
Allowance for loan losses:
Allowance for loan losses, beginning of period	1,103	636	1,030	726
Loans charged off
Recoveries
Provision	(458)	349	(385)	259
Allowance for loan losses, end of period	645	985	645	985
Amount of allowance for loan losses for loans deemed to be impaired
Amount of allowance for loan losses for loans not deemed to be impaired			645	985
Loans:
Ending balance
Loans deemed to be impaired
Loans not deemed to be impaired

Amount of allowance for loan losses for loans deemed to be impaired.

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Amount of allowance for loans losses for loans not deemed to be impaired.

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Reflects the gross amount charged against earnings during the period as credit losses (bad debt expense) based on review of the loan and lease portfolio and application of the methodology for estimating credit losses.

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Reflects a reduction in bad debt expense attributable to collections of loans and lease receivables which had previously been fully or partially charged off as bad debts.

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Reflects the amount of loans and leases that have been removed, or charged off, from both loan receivables and the reserve for credit losses, typically because they are considered to be not salvageable or have been purchased by unconsolidated collection entities.

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For loans and debt securities, 1) for which at acquisition it was probable that the investor would be unable to collect all contractually required payments receivable, and 2) for which it is further probable that the investor will not be able to collect all cash flows expected at acquisition (plus any additional cash flows expected due to changes in estimate after acquisition), the allowance for credit losses recorded to reflect the impairment since acquisition.

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The recorded amount of loans and debt securities, with evidence of deterioration of credit quality since origination that were acquired by completion of a transfer for which it was probable, at acquisition, that the investor would be unable to collect all contractually required payments receivable, but which are not deemed to be impaired since the acquisition by transfer. Therefore, no allowance for credit losses is recorded.

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The recorded amount of loans and debt securities, with evidence of deterioration of credit quality since origination that were acquired by completion of a transfer for which it was probable, at acquisition, that the investor would be unable to collect all contractually required payments receivable. They are deemed to be impaired since the acquisition and an allowance for credit losses has been recorded. Disclosure is gross of the allowance.

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Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for loans and leases covered under loss sharing agreements.

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