Note 4 - Loans and Allowance for Loan Losses (Detail) - Net (Charge-Offs)/Recoveries (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2012	Jun. 30, 2011
Consumer:
Net (charge-offs)/recoveries	$ (703)	$ (3,437)	$ (3,257)	$ (4,623)
Credit Cards [Member]
Consumer:
Net (charge-offs)/recoveries	(617)	(908)	(1,404)	(1,827)
Student Loans [Member]
Consumer:
Net (charge-offs)/recoveries	(20)	(14)	(38)	(22)
Other Consumer [Member]
Consumer:
Net (charge-offs)/recoveries	(97)	(476)	(149)	(603)
Consumer Loans [Member]
Consumer:
Net (charge-offs)/recoveries	(734)	(1,398)	(1,591)	(2,452)
Construction Loans [Member]
Consumer:
Net (charge-offs)/recoveries		(772)	46	(772)
Single Family Residential Loans [Member]
Consumer:
Net (charge-offs)/recoveries	9	(338)	(211)	(355)
Other Commercial Real Estate Loans [Member]
Consumer:
Net (charge-offs)/recoveries	161	(425)	(1,274)	(504)
Real Estate Loans [Member]
Consumer:
Net (charge-offs)/recoveries	170	(1,535)	(1,439)	(1,631)
Other Commercial Loans [Member]
Consumer:
Net (charge-offs)/recoveries	11	(503)	(43)	(571)
Agricultural Loans [Member]
Consumer:
Net (charge-offs)/recoveries	(150)	(1)	(184)	31
Commercial Loans [Member]
Consumer:
Net (charge-offs)/recoveries	$ (139)	$ (504)	$ (227)	$ (540)