Note 6 - Fair Value Measurements (Detail) - Quantitative Information About Unobservable Inputs for Assets Measured on A Nonrecurring Basis Using Level 3 Measurements (Fair Value, Inputs, Level 3 [Member], USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2013 Impaired Loans [Member]	Mar. 31, 2013 OREO [Member]	Mar. 31, 2013	Dec. 31, 2012
Impaired loans (in Dollars)	$ 1,011		$ 994,841	$ 979,301
Impaired loans	Discounted appraisals	Discounted appraisals
Impaired loans	Marketability discount	Marketability discount
Impaired loans	0.00%	1.20%
Impaired loans	4.70%	57.10%
Impaired loans	0.90%	5.90%
OREO (in Dollars)		$ 14,690
OREO	Discounted appraisals	Discounted appraisals
OREO	Marketability discount	Marketability discount
OREO	0.00%	1.20%
OREO	4.70%	57.10%
OREO	0.90%	5.90%