Trust Preferred Capital Notes - Outstanding Payables (Details) (USD $)									12 Months Ended				12 Months Ended		12 Months Ended
	Dec. 31, 2013	Dec. 31, 2013 AMNB Trust I [Member]	Dec. 31, 2013 MidCarolina I [Member]	Jul. 01, 2011 MidCarolina I [Member]	Dec. 31, 2013 MidCarolina II [Member]	Jul. 01, 2011 MidCarolina II [Member]	Dec. 31, 2013 MidCarolina Trust [Member]	Jul. 01, 2011 MidCarolina Trust [Member]	Dec. 31, 2013 Junior Subordinated Debt Securities [Member]	Dec. 31, 2012 Junior Subordinated Debt Securities [Member]	Dec. 31, 2013 Junior Subordinated Debt Securities [Member] AMNB Trust I [Member]	Dec. 31, 2012 Junior Subordinated Debt Securities [Member] AMNB Trust I [Member]	Dec. 31, 2013 Junior Subordinated Debt Securities [Member] MidCarolina I [Member]	Dec. 31, 2012 Junior Subordinated Debt Securities [Member] MidCarolina I [Member]	Dec. 31, 2013 Junior Subordinated Debt Securities [Member] MidCarolina II [Member]	Dec. 31, 2012 Junior Subordinated Debt Securities [Member] MidCarolina II [Member]
Debt Instrument [Line Items]
Date Issued									Apr. 07, 2006				Oct. 29, 2002		Dec. 03, 2003
Interest Rate									Libor plus 1.35%				Libor plus 3.45%		Libor plus 2.95%
Variable Rate Basis									Libor plus				Libor plus		Libor plus
Basis Spread on Variable Rate (in hundredths)									1.35%				3.45%		2.95%
Maturity Date									Jun. 30, 1936				Nov. 07, 1932		Oct. 07, 1933
Principal Amount	$ 20,619,000							$ 8,764,000	$ 27,419,000	$ 27,317,000	$ 20,619,000	$ 20,619,000	$ 4,098,000	$ 4,042,000	$ 2,702,000	$ 2,656,000
Valuation allowance associated with junior subordinated debenture			1,057,000	1,197,000	907,000	1,021,000
Equity Method Investments		$ 619,000					$ 264,000