Note 7 - Other Real Estate Owned (Detail) (USD $)	3 Months Ended		12 Months Ended			12 Months Ended
	Mar. 31, 2013	Mar. 31, 2012	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2012 Citizens South Banking Corporation [Member]	Dec. 31, 2011 Community Capital [Member]
Other Real Estate, Foreclosed Assets, and Repossessed Assets	$ 21,251,000	$ 16,674,000	$ 25,073,000	$ 14,403,000
Other Real Estate Acquired in Merger			16,100,000
Other Real Estate, Covered	7,654,000		6,646,000		6,700,000
Real Estate, Other Acquisitions						7,800,000
Transfer to Other Real Estate	$ 3,200,000	$ 4,400,000