Note 4 - Loans and Allowance for Credit Losses (Detail) - Impaired loans, supplemental schedule (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011
Average Recored Investment	$ 51,496	$ 73,483
Recognized Interest Income	1,723	2,824
Commercial [Member]
Average Recored Investment	12,996	14,315
Recognized Interest Income	239	586
Commercial Real Estate Loans [Member]
Average Recored Investment	28,420	37,873
Recognized Interest Income	1,225	1,740
Construction [Member]
Average Recored Investment	6,651	18,436
Recognized Interest Income	216	455
Residential Real Estate Loans [Member]
Average Recored Investment	818	281
Consumer Installment And Other [Member]
Average Recored Investment	2,611	2,578
Recognized Interest Income	$ 43	$ 43