Condensed Financial Information - Parent Corporation Only (Details) (USD $)	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
ASSETS [Abstract]
Cash on deposit with subsidiary bank	$ 7,139,000	$ 6,163,000
Investment securities available for sale	319,457,000	308,242,000
Investment in subsidiaries	155,000	155,000
TOTAL ASSETS	1,236,781,000	1,192,860,000	1,104,567,000
LIABILITIES [Abstract]
Trust-preferred capital notes	5,155,000	5,155,000
TOTAL LIABILITIES	1,119,659,000	1,084,847,000
SHAREHOLDERS' EQUITY [Abstract]
Common stock	17,357,000	17,331,000
Capital surplus	43,869,000	43,498,000
Retained earnings	46,235,000	41,157,000
Accumulated other comprehensive income (loss), net	6,467,000	3,926,000
TOTAL SHAREHOLDERS' EQUITY	117,122,000	108,013,000	99,993,000	103,359,000
TOTAL LIABILITIES AND SHAREHOLDERS' EQUITY	1,236,781,000	1,192,860,000
INCOME [Abstract]
Interest and dividends from investments	47,023,000	48,636,000	48,031,000
EXPENSES [Abstract]
Salaries and employee benefits	30,417,000	27,373,000	24,103,000
Amortization	171,000	171,000	171,000
Interest expense	8,824,000	10,691,000	14,175,000
Other	8,602,000	7,354,000	9,331,000
Income (loss) before allocated tax benefits and undistributed (distributions in excess of) income of subsidiaries	9,956,000	6,012,000	(4,888,000)
Income tax (benefit)	1,966,000	1,350,000	(2,562,000)
Net income (loss)	6,486,000	4,960,000	(2,688,000)
CASH FLOWS FROM OPERATING ACTIVITIES [Abstract]
Net income (loss)	6,486,000	4,960,000	(2,688,000)
Adjustments to reconcile net income (loss) to net cash provided by operating activities:
Amortization	171,000	171,000	171,000
Equity in undistributed (earnings) losses of subsidiaries	(37,000)	(20,000)	(244,000)
Share-based compensation	440,000	471,000	158,000
Deferred income taxes	1,207,000	525,000	(3,173,000)
(Increase) decrease in other assets	4,968,000	3,710,000	2,736,000
Increase (decrease) in other liabilities	1,950,000	(426,000)	844,000
Net cash provided by (used in) operating activities	28,356,000	(21,497,000)	(381,000)
CASH FLOWS FROM INVESTING ACTIVITIES [Abstract]
Proceeds from sale of securities available for sale	41,010,000	37,564,000	68,757,000
Net cash (used in) investing activities	(56,211,000)	(70,604,000)	(106,160,000)
CASH FLOWS FROM FINANCING ACTIVITIES [Abstract]
Net proceeds from issuance of common stock	0	0	134,000
Cash dividends paid on common stock	1,408,000	1,396,000	2,425,000
Net cash provided by (used in) financing activities	31,000,000	78,647,000	128,055,000
Increase (decrease) in cash and cash equivalents	3,145,000	(13,454,000)	21,514,000
Beginning	51,270,000	64,724,000	43,210,000
Ending	54,415,000	51,270,000	64,724,000
Middleburg Financial Corporation [Member]
ASSETS [Abstract]
Cash on deposit with subsidiary bank	353,000	493,000
Money market fund	7,000	7,000
Investment securities available for sale	33,000	11,000
Investment in subsidiaries	112,145,000	103,999,000
Goodwill	5,289,000	5,289,000
Intangible assets, net	728,000	900,000
Other assets	580,000	736,000
TOTAL ASSETS	119,135,000	111,435,000
LIABILITIES [Abstract]
Trust-preferred capital notes	5,155,000	5,155,000
Other liabilities	52,000	368,000
TOTAL LIABILITIES	5,207,000	5,523,000
SHAREHOLDERS' EQUITY [Abstract]
Common stock	17,357,000	17,331,000
Capital surplus	43,869,000	43,498,000
Retained earnings	46,235,000	41,157,000
Accumulated other comprehensive income (loss), net	6,467,000	3,926,000
TOTAL SHAREHOLDERS' EQUITY	113,928,000	105,912,000
TOTAL LIABILITIES AND SHAREHOLDERS' EQUITY	119,135,000	111,435,000
INCOME [Abstract]
Dividends from subsidiaries	1,880,000	1,047,000	1,732,000
Interest and dividends from investments	0	5,000	5,000
Other income (loss)	37,000	(2,000)	10,000
Total income	1,917,000	1,050,000	1,747,000
EXPENSES [Abstract]
Salaries and employee benefits	517,000	540,000	366,000
Amortization	171,000	171,000	171,000
Legal and professional fees	27,000	177,000	141,000
Directors fees	251,000	192,000	100,000
Interest expense	280,000	280,000	184,000
Other	245,000	221,000	339,000
Total expenses	1,491,000	1,581,000	1,301,000
Income (loss) before allocated tax benefits and undistributed (distributions in excess of) income of subsidiaries	426,000	(531,000)	446,000
Income tax (benefit)	(559,000)	539,000	(387,000)
Income before equity in undistributed (distributions in excess of) income of subsidiaries	985,000	8,000	833,000
Equity in undistributed (distributions in excess of) income of subsidiaries	5,501,000	4,952,000	(3,521,000)
Net income (loss)	6,486,000	4,960,000	(2,688,000)
CASH FLOWS FROM OPERATING ACTIVITIES [Abstract]
Net income (loss)	6,486,000	4,960,000	(2,688,000)
Adjustments to reconcile net income (loss) to net cash provided by operating activities:
Amortization	171,000	171,000	171,000
Equity in undistributed (earnings) losses of subsidiaries	(5,672,000)	(5,138,000)	3,350,000
Share-based compensation	440,000	471,000	159,000
(Increase) decrease in other assets	(112,000)	(508,000)	(519,000)
Increase (decrease) in other liabilities	(2,000)	(7,000)	0
Net cash provided by (used in) operating activities	1,311,000	(51,000)	473,000
CASH FLOWS FROM INVESTING ACTIVITIES [Abstract]
Investment in subsidiary bank	0	0	0
Net cash (used in) investing activities	0	0	0
CASH FLOWS FROM FINANCING ACTIVITIES [Abstract]
Net proceeds from issuance of common stock	0	0	134,000
Cash dividends paid on common stock	(1,408,000)	(1,396,000)	(2,425,000)
Other, net	(43,000)	0	0
Net cash provided by (used in) financing activities	(1,451,000)	(1,396,000)	(2,291,000)
Increase (decrease) in cash and cash equivalents	(140,000)	(1,447,000)	(1,818,000)
Beginning	500,000	1,947,000	3,765,000
Ending	$ 360,000	$ 500,000	$ 1,947,000