Capital Requirements (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2012	Dec. 31, 2011
Middleburg Bank [Member]
Total Capital (to Risk- Weighted Assets), Amount [Abstract]
Actual	$ 115,411	$ 108,835
Minimum Capital Requirement	62,430	60,941
Minimum To Be Well Capitalized Under Prompt Corrective Action Provisions	78,038	76,176
Total Capital (to Risk- Weighted Assets), Ratio [Abstract]
Actual, Ratio (in hundredths)	14.80%	14.30%
Minimum Capital Requirement, 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), Amount [Abstract]
Actual	105,601	99,249
Minimum Capital Requirement	31,215	30,471
Minimum To Be Well Capitalized Under Prompt Corrective Action Provisions	46,823	45,706
Tier 1 Capital (to Risk- Weighted Assets), Ratio [Abstract]
Actual, Ratio (in hundredths)	13.50%	13.00%
Minimum Capital Requirement, 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), Amount [Abstract]
Actual	105,601	99,249
Minimum Capital Requirement	48,399	46,684
Minimum To Be Well Capitalized Under Prompt Corrective Action Provisions	60,499	58,355
Tier 1 Capital (to Average Assets), Ratio [Abstract]
Actual, Ratio (in hundredths)	8.70%	8.50%
Minimum Capital Requirement, Ratio (in hundredths)	4.00%	4.00%
Minimum To Be Well Capitalized Under Prompt Corrective Action Provisions, Ratio (in hundredths)	5.00%	5.00%
Middleburg Financial Corporation [Member]
Total Capital (to Risk- Weighted Assets), Amount [Abstract]
Actual	119,479	112,499
Minimum Capital Requirement	62,640	61,155
Total Capital (to Risk- Weighted Assets), Ratio [Abstract]
Actual, Ratio (in hundredths)	15.30%	14.70%
Minimum Capital Requirement, Ratio (in hundredths)	8.00%	8.00%
Tier 1 Capital (to Risk- Weighted Assets), Amount [Abstract]
Actual	109,634	102,880
Minimum Capital Requirement	31,320	30,578
Tier 1 Capital (to Risk- Weighted Assets), Ratio [Abstract]
Actual, Ratio (in hundredths)	14.00%	13.50%
Minimum Capital Requirement, Ratio (in hundredths)	4.00%	4.00%
Tier 1 Capital (to Average Assets), Amount [Abstract]
Actual	109,634	102,880
Minimum Capital Requirement	$ 48,477	$ 46,735
Tier 1 Capital (to Average Assets), Ratio [Abstract]
Actual, Ratio (in hundredths)	9.10%	8.80%
Minimum Capital Requirement, Ratio (in hundredths)	4.00%	4.00%

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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 amount of Tier 1 Leverage Capital required to be categorized as well capitalized under the regulatory framework for prompt corrective action.

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Tier 1 Risk Based Capital as defined in the regulations.

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

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The minimum Tier One Capital Ratio (Tier one capital divided by risk-weighted assets) required for capital adequacy purposes under the regulatory framework for prompt corrective action.

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

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