Note 12 - Fair Value Measurements (Detail) - Assets measured at fair value on a nonrecurring basis (USD $) In Thousands, unless otherwise specified	Dec. 31, 2012	Dec. 31, 2011
Fair Value	$ 26,428	$ 19,547
Total losses	(4,972)	(1,578)
Non-Covered Other Real Estate Owned [Member] | Fair Value, Inputs, Level 2 [Member]
Fair Value	6,618	6,350
Non-Covered Other Real Estate Owned [Member]
Fair Value	6,618	6,350
Total losses	(1,360)	(1,000)
Covered Other Real Estate Owned [Member] | Fair Value, Inputs, Level 2 [Member]
Fair Value	7,929	10,695
Covered Other Real Estate Owned [Member]
Fair Value	7,929	10,695
Total losses	(371)	(578)
Originated Impaired Loans [Member] | Fair Value, Inputs, Level 2 [Member]
Fair Value	3,097	2,502
Originated Impaired Loans [Member] | Fair Value, Inputs, Level 3 [Member]
Fair Value	2,100
Originated Impaired Loans [Member]
Fair Value	5,197	2,502
Total losses	(3,158)
Purchased Covered Impaired Loans [Member] | Fair Value, Inputs, Level 2 [Member]
Fair Value	2,224
Purchased Covered Impaired Loans [Member] | Fair Value, Inputs, Level 3 [Member]
Fair Value	4,460
Purchased Covered Impaired Loans [Member]
Fair Value	6,684
Total losses	(83)
Fair Value, Inputs, Level 2 [Member]
Fair Value	19,868	19,547
Fair Value, Inputs, Level 3 [Member]
Fair Value	$ 6,560