Allowance for Loan Losses (Details 1) (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2013	Mar. 31, 2012
Allowance for loan losses:
Allowance for loan losses, beginning of period	$ 19,197	$ 16,574
Loans charged off	(371)	(424)
Recoveries	183	184
Provision	750	1,100
Allowance for loan losses, end of period	19,759	17,434
Amount of allowance for loan losses for loans deemed to be impaired	1,750	2,111
Amount of allowance for loan losses for loans not deemed to be impaired	18,009	15,323
Loans:
Ending balance	1,137,769	987,976
Loans deemed to be impaired	6,486	8,277
Loans not deemed to be impaired	1,131,283	979,699
Construction and Land Development [Member]
Allowance for loan losses:
Allowance for loan losses, beginning of period	3,041	2,893
Provision	158	27
Allowance for loan losses, end of period	3,199	2,920
Amount of allowance for loan losses for loans deemed to be impaired	1,000	1,000
Amount of allowance for loan losses for loans not deemed to be impaired	2,199	1,920
Loans:
Ending balance	34,021	36,937
Loans deemed to be impaired	1,500	1,500
Loans not deemed to be impaired	32,521	35,437
Commercial and Industrial [Member]
Allowance for loan losses:
Allowance for loan losses, beginning of period	3,118	3,139
Loans charged off	(226)	(111)
Recoveries	65	42
Provision	566	150
Allowance for loan losses, end of period	3,523	3,220
Amount of allowance for loan losses for loans deemed to be impaired	103	493
Amount of allowance for loan losses for loans not deemed to be impaired	3,420	2,727
Loans:
Ending balance	110,537	81,882
Loans deemed to be impaired	1,396	1,721
Loans not deemed to be impaired	109,141	80,161
Commercial Real Estate [Member]
Allowance for loan losses:
Allowance for loan losses, beginning of period	9,065	6,566
Recoveries	2	1
Provision	(288)	774
Allowance for loan losses, end of period	8,779	7,341
Amount of allowance for loan losses for loans deemed to be impaired	396	525
Amount of allowance for loan losses for loans not deemed to be impaired	8,383	6,816
Loans:
Ending balance	570,441	502,413
Loans deemed to be impaired	2,262	4,541
Loans not deemed to be impaired	568,179	497,872
Residential Real Estate [Member]
Allowance for loan losses:
Allowance for loan losses, beginning of period	1,994	1,886
Loans charged off		(159)
Recoveries	2	5
Provision	75	52
Allowance for loan losses, end of period	2,071	1,784
Amount of allowance for loan losses for loans deemed to be impaired	155	93
Amount of allowance for loan losses for loans not deemed to be impaired	1,916	1,691
Loans:
Ending balance	292,871	249,981
Loans deemed to be impaired	1,232	515
Loans not deemed to be impaired	291,639	249,466
Consumer [Member]
Allowance for loan losses:
Allowance for loan losses, beginning of period	333	356
Loans charged off	(145)	(154)
Recoveries	114	136
Provision	55	(21)
Allowance for loan losses, end of period	357	317
Amount of allowance for loan losses for loans not deemed to be impaired	357	317
Loans:
Ending balance	7,910	6,946
Loans not deemed to be impaired	7,910	6,946
Home Equity [Member]
Allowance for loan losses:
Allowance for loan losses, beginning of period	886	704
Recoveries
Provision	(53)	37
Allowance for loan losses, end of period	833	741
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	737	741
Loans:
Ending balance	121,989	109,817
Loans deemed to be impaired	96
Loans not deemed to be impaired	121,893	109,817
Unallocated [Member]
Allowance for loan losses:
Allowance for loan losses, beginning of period	760	1,030
Provision	237	81
Allowance for loan losses, end of period	997	1,111
Amount of allowance for loan losses for loans not deemed to be impaired	$ 997	$ 1,111

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

No definition available.

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- Definition

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

+ References

No definition available.

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- Definition

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.

+ References

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- Definition

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.

+ References

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- Definition

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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- Definition

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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- Definition

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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- Definition

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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