Regulatory Capital (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2012	Dec. 31, 2011
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Tier 1 Capital (to Average Assets) (in hundredths)	5.00%	5.00%
Tier 1 Capital (to Risk Weighted Assets) (in hundredths)	6.00%	6.00%
Total Capital (to Risk Weighted Assets) (in hundredths)	10.00%	10.00%
Total Capital (to risk-weighted assets) [Abstract]
Actual capital ratios, Amount	$ 162,458	$ 146,990
Minimum for capital adequacy, Amount	72,020	82,756
Minimum to be "Well Capitalized" under prompt corrective action provisions, Amount	90,025	103,445
Total Capital (to risk-weighted assets) Ratios [Abstract]
Actual capital ratios, Ratio (in hundredths)	18.05%	14.21%
Minimum for capital adequacy, Ratio (in hundredths)	8.00%	8.00%
Minimum to be "Well Capitalized" under prompt corrective action provisions, Ratio (in hundredths)	10.00%	10.00%
Tier 1 Capital (to risk-weighted assets) [Abstract]
Actual capital ratios, Amount	151,121	133,716
Minimum for capital adequacy, Amount	36,010	41,378
Minimum to be "Well Capitalized" under prompt corrective action provisions, Amount	54,015	62,067
Tier 1 Capital (to risk-weighted assets) Ratio [Abstract]
Actual capital ratios, ratio (in hundredths)	16.79%	12.93%
Minimum for capital adequacy, Ratio (in hundredths)	4.00%	4.00%
Minimum to be "Well Capitalized" under prompt corrective action provisions, Ratio (in hundredths)	6.00%	6.00%
Tier 1 Capital (to average assets) [Abstract]
Actual capital ratios, Amount	151,121	133,716
Minimum for capital adequacy, Amount	62,092	60,726
Minimum to be "Well Capitalized" under prompt corrective action provisions, Amount	$ 77,615	$ 75,907
Tier 1 Capital (to average assets) Ratios [Abstract]
Actual capital ratios, ratio (in hundredths)	9.74%	8.81%
Minimum for capital adequacy, Ratio (in hundredths)	4.00%	4.00%
Minimum to be "Well Capitalized" under prompt corrective action provisions, Ratio (in hundredths)	5.00%	5.00%
Tier 1 Leverage Capital ratio (in hundredths)	9.74%	8.81%
Tier 1 Risk-based Capital Ratio (in hundredths)	16.79%	12.93%
Total Risk-based Capital Ratio (in hundredths)	18.05%	14.21%
Bank [Member]
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Tier 1 Capital (to Average Assets) (in hundredths)	8.00%
Tier 1 Capital (to Risk Weighted Assets) (in hundredths)	10.50%
Total Capital (to Risk Weighted Assets) (in hundredths)	12.00%
Total Capital (to risk-weighted assets) Ratios [Abstract]
Actual capital ratios, Ratio (in hundredths)	18.05%
Minimum to be "Well Capitalized" under prompt corrective action provisions, Ratio (in hundredths)	12.00%
Tier 1 Capital (to risk-weighted assets) Ratio [Abstract]
Actual capital ratios, ratio (in hundredths)	16.79%
Minimum to be "Well Capitalized" under prompt corrective action provisions, Ratio (in hundredths)	10.50%
Tier 1 Capital (to average assets) Ratios [Abstract]
Actual capital ratios, ratio (in hundredths)	9.74%
Minimum to be "Well Capitalized" under prompt corrective action provisions, Ratio (in hundredths)	8.00%
Tier 1 Leverage Capital ratio (in hundredths)	9.74%
Tier 1 Risk-based Capital Ratio (in hundredths)	16.79%
Total Risk-based Capital Ratio (in hundredths)	18.05%
Parent Company [Member]
Total Capital (to risk-weighted assets) Ratios [Abstract]
Actual capital ratios, Ratio (in hundredths)	18.15%	14.26%
Tier 1 Capital (to risk-weighted assets) Ratio [Abstract]
Actual capital ratios, ratio (in hundredths)	16.89%	12.98%
Tier 1 Capital (to average assets) Ratios [Abstract]
Actual capital ratios, ratio (in hundredths)	9.79%	8.85%
Tier 1 Leverage Capital ratio (in hundredths)	9.79%	8.85%
Tier 1 Risk-based Capital Ratio (in hundredths)	16.89%	12.98%
Total Risk-based Capital Ratio (in hundredths)	18.15%	14.26%

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The amount of total capital as defined in the regulations.

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The minimum Total risk based capital ratio (total capital divided by risk weighted assets) required for capital adequacy purposes under the regulatory framework for prompt corrective action.

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The amount of Total Capital required to be categorized as well as capitalized under the regulatory framework for prompt corrective action.

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Tier 1 Leverage Capital as defined in the regulations. Also called Core Capital.

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Tier 1 Risk Based Capital as defined in the regulations.

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Tier 1 capital divided by risk weighted assets as defined by regulations.

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