Note 4 - Loans and Allowance for Loan Losses (Detail) - Activity in the allowance for loan losses, by portfolio segment (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2013	Mar. 31, 2012	Dec. 31, 2012
Balance, beginning of period	$ 27,882	$ 30,108
Provision for loan losses	919	771
Charge-offs	(1,618)	(3,891)
Recoveries	552	1,337
Net charge-offs	(1,066)	(2,554)
Balance	27,735	28,325
Period-end amount allocated to:
Loans individually evaluated for impairment	3,081	2,837	2,843
Loans collectively evaluated for impairment	24,654	25,488	25,039
Commercial and Residential Real Estate Collateral [Member]
Balance, beginning of period	3,446	2,063
Provision for loan losses	129	(61)
Charge-offs	(96)	(129)
Recoveries	53	41
Net charge-offs	(43)	(88)
Balance	3,532	1,914
Period-end amount allocated to:
Loans individually evaluated for impairment	221	290	203
Loans collectively evaluated for impairment	3,311	1,624	3,243
Real Estate Loans [Member]
Balance, beginning of period	15,453	10,117
Provision for loan losses	849	1,133
Charge-offs	(239)	(2,539)
Recoveries	68	930
Net charge-offs	(171)	(1,609)
Balance	16,131	9,641
Period-end amount allocated to:
Loans individually evaluated for impairment	2,495	2,244	2,309
Loans collectively evaluated for impairment	13,636	7,397	13,144
Credit Cards [Member]
Balance, beginning of period	7,211	5,513
Provision for loan losses	261	774
Charge-offs	(909)	(997)
Recoveries	236	210
Net charge-offs	(673)	(787)
Balance	6,799	5,500
Period-end amount allocated to:
Loans individually evaluated for impairment	74	83	82
Loans collectively evaluated for impairment	6,725	5,417	7,129
Other Consumer and Other Loans [Member]
Balance, beginning of period	1,772	1,847
Provision for loan losses	(320)	(6)
Charge-offs	(374)	(226)
Recoveries	195	156
Net charge-offs	(179)	(70)
Balance	1,273	1,771
Period-end amount allocated to:
Loans individually evaluated for impairment	291	220	249
Loans collectively evaluated for impairment	982	1,551	1,523
Unallocated Financing Receivables [Member]
Balance, beginning of period		10,568
Provision for loan losses		(1,069)
Balance		9,499
Period-end amount allocated to:
Loans collectively evaluated for impairment		$ 9,499