Note 4 - Loans and Allowance for Loan Losses (Detail) - Recorded Investment in Loans (USD $) In Thousands, unless otherwise specified	Sep. 30, 2012	Dec. 31, 2011
Loans individually evaluated for impairment	$ 33,948	$ 40,108
Loans collectively evaluated for impairment	1,589,453	1,539,661
Balance, end of period	1,623,401	1,579,769
Commercial Loans [Member]
Loans individually evaluated for impairment	997	1,317
Loans collectively evaluated for impairment	268,449	225,833
Balance, end of period	269,446	227,150
Real Estate Loans [Member]
Loans individually evaluated for impairment	31,209	36,855
Loans collectively evaluated for impairment	999,414	964,436
Balance, end of period	1,030,623	1,001,291
Credit Cards [Member]
Loans individually evaluated for impairment	595	605
Loans collectively evaluated for impairment	175,165	189,365
Balance, end of period	175,760	189,970
Other Consumer and Other Loans [Member]
Loans individually evaluated for impairment	1,147	1,331
Loans collectively evaluated for impairment	146,425	160,027
Balance, end of period	$ 147,572	$ 161,358