Allowance for Loan Losses (Details 1) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Allowance for loan losses:
Allowance for loan losses, beginning of year	$ 16,574	$ 14,053	$ 12,373
Loans charged-off	(2,301)	(2,824)	(4,443)
Recoveries	774	795
Provision	4,150	4,550	5,575
Allowance for loan losses, end of year	19,197	16,574	14,053
Amount of allowance for loan losses for loans deemed to be impaired	1,732	741
Amount of allowance for loan losses for loans not deemed to be impaired	17,465	15,833
Loans:
Ending balance	1,111,788	984,492
Loans deemed to be impaired	5,925	8,102
Loans not deemed to be impaired	1,105,863	976,390
Construction and Land Development [Member]
Allowance for loan losses:
Allowance for loan losses, beginning of year	2,893	1,752
Loans charged-off		(1,200)
Recoveries
Provision	148	2,341
Allowance for loan losses, end of year	3,041	2,893
Amount of allowance for loan losses for loans deemed to be impaired	1,000
Amount of allowance for loan losses for loans not deemed to be impaired	2,041	2,893
Loans:
Ending balance	38,618	56,819
Loans deemed to be impaired	1,500	1,500
Loans not deemed to be impaired	37,118	55,319
Commercial and Industrial [Member]
Allowance for loan losses:
Allowance for loan losses, beginning of year	3,139	3,163
Loans charged-off	(1,253)	(676)
Recoveries	307	293
Provision	925	359
Allowance for loan losses, end of year	3,118	3,139
Amount of allowance for loan losses for loans deemed to be impaired	104	335
Amount of allowance for loan losses for loans not deemed to be impaired	3,014	2,804
Loans:
Ending balance	88,475	82,404
Loans deemed to be impaired	1,282	1,525
Loans not deemed to be impaired	87,193	80,879
Commercial Real Estate [Member]
Allowance for loan losses:
Allowance for loan losses, beginning of year	6,566	5,671
Loans charged-off
Recoveries	9	6
Provision	2,490	889
Allowance for loan losses, end of year	9,065	6,566
Amount of allowance for loan losses for loans deemed to be impaired	415	282
Amount of allowance for loan losses for loans not deemed to be impaired	8,650	6,284
Loans:
Ending balance	576,465	487,495
Loans deemed to be impaired	2,281	4,561
Loans not deemed to be impaired	574,184	482,934
Residential Real Estate [Member]
Allowance for loan losses:
Allowance for loan losses, beginning of year	1,886	1,718
Loans charged-off	(192)	(337)
Recoveries	17	27
Provision	283	478
Allowance for loan losses, end of year	1,994	1,886
Amount of allowance for loan losses for loans deemed to be impaired	117	124
Amount of allowance for loan losses for loans not deemed to be impaired	1,877	1,762
Loans:
Ending balance	281,857	239,307
Loans deemed to be impaired	766	516
Loans not deemed to be impaired	281,091	238,791
Consumer [Member]
Allowance for loan losses:
Allowance for loan losses, beginning of year	356	298
Loans charged-off	(697)	(607)
Recoveries	422	467
Provision	252	198
Allowance for loan losses, end of year	333	356
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	333	356
Loans:
Ending balance	7,450	7,681
Loans deemed to be impaired
Loans not deemed to be impaired	7,450	7,681
Home Equity [Member]
Allowance for loan losses:
Allowance for loan losses, beginning of year	704	725
Loans charged-off	(159)	(4)
Recoveries	19	2
Provision	322	(19)
Allowance for loan losses, end of year	886	704
Amount of allowance for loan losses for loans deemed to be impaired	96
Amount of allowance for loan losses for loans not deemed to be impaired	790	704
Loans:
Ending balance	118,923	110,786
Loans deemed to be impaired	96
Loans not deemed to be impaired	118,827	110,786
Unallocated [Member]
Allowance for loan losses:
Allowance for loan losses, beginning of year	1,030	726
Loans charged-off
Recoveries
Provision	(270)	304
Allowance for loan losses, end of year	760	1,030
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	760	1,030
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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