Capital Requirements (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2012	Dec. 31, 2011
Actual Amount [Abstract]
Total capital (to risk-weighted assets)	$ 58,806	$ 58,400
Tier 1 capital (to risk-weighted assets)	53,460	52,899
Tier 1 capital (to average assets)	53,460	52,899
Actual Ratio [Abstract]
Total capital (to risk-weighted assets) (in hundredths)	13.80%	13.30%
Tier 1 capital (to risk-weighted assets) (in hundredths)	12.50%	12.10%
Tier 1 capital (to average assets) (in hundredths)	9.10%	8.70%
Minimum Capital Requirement Amount [Abstract]
Total capital (to risk-weighted assets)	34,148	35,106
Tier 1 capital (to risk-weighted assets)	17,074	17,553
Tier 1 capital (to average assets)	23,457	24,332
Minimum Capital Requirement Ratio [Abstract]
Total capital (to risk-weighted assets) (in hundredths)	8.00%	8.00%
Tier 1 capital (to risk-weighted assets) (in hundredths)	4.00%	4.00%
Tier 1 Capital (to average assets) (in hundredths)	4.00%	4.00%
The Fauquier Bank [Member]
Actual Amount [Abstract]
Total capital (to risk-weighted assets)	56,696	56,640
Tier 1 capital (to risk-weighted assets)	51,353	51,138
Tier 1 capital (to average assets)	51,353	51,138
Actual Ratio [Abstract]
Total capital (to risk-weighted assets) (in hundredths)	13.30%	12.90%
Tier 1 capital (to risk-weighted assets) (in hundredths)	12.00%	11.70%
Tier 1 capital (to average assets) (in hundredths)	8.80%	8.40%
Minimum Capital Requirement Amount [Abstract]
Total capital (to risk-weighted assets)	34,117	35,113
Tier 1 capital (to risk-weighted assets)	17,059	17,557
Tier 1 capital (to average assets)	23,378	24,266
Minimum Capital Requirement Ratio [Abstract]
Total capital (to risk-weighted assets) (in hundredths)	8.00%	8.00%
Tier 1 capital (to risk-weighted assets) (in hundredths)	4.00%	4.00%
Tier 1 Capital (to average assets) (in hundredths)	4.00%	4.00%
Well Capitalized Under Prompt Corrective Action Provisions Amount [Abstract]
Total capital (to risk-weighted assets)	42,647	43,892
Tier 1 capital (to risk-weighted assets)	25,588	26,335
Tier 1 capital (to average assets)	$ 29,222	$ 30,333
Well Capitalized Under Prompt Corrective Action Provisions Ratio [Abstract]
Total capital (to risk-weighted assets) (in hundredths)	10.00%	10.00%
Tier 1 capital (to risk-weighted assets) (in hundredths)	6.00%	6.00%
Tier 1 capital (to average assets) (in hundredths)	5.00%	5.00%

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The amount of total capital as defined in the regulations.

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The minimum amount of Total Capital required for capital adequacy purposes under the regulatory framework for prompt corrective action.

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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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The Total risk based capital ratio (total capital divided by risk weighted assets) required to be categorized as "well capitalized", in the regulatory framework for prompt corrective action.

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Total Capital divided by risk weighted assets as defined in the regulations.

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

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The minimum amount of Tier 1 Leverage Capital required for capital adequacy purposes under the regulatory framework for prompt corrective action.

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The minimum amount of Tier 1 Leverage Capital for capital adequacy purposes divided by average assets as defined in the regulations.

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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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