Note 5 - Investment Securities Available-for-sale (Details) - Reconciliation of Available-for-sale Securities in Continuous Unrealized Loss Position $ in Thousands	Jun. 30, 2015 USD ($)	Dec. 31, 2014 USD ($)
Note 5 - Investment Securities Available-for-sale (Details) - Reconciliation of Available-for-sale Securities in Continuous Unrealized Loss Position [Line Items]
Investment securities available for sale in an unrealized loss position less than 12 months, number of securities	21	27
Investment securities available for sale in an unrealized loss position less than 12 months, fair value	$ 23,045	$ 52,184
Investment securities available for sale in an unrealized loss position less than 12 months, gross unrealized losses	$ 286	$ 328
Investment securities available for sale in an unrealized loss position 12 months or longer, number of securities	24	27
Investment securities available for sale in an unrealized loss position 12 months or longer, fair value	$ 63,551	$ 87,815
Investment securities available for sale in an unrealized loss position 12 months or longer, gross unrealized losses	$ 1,203	$ 1,746
Investment securities available for sale in an unrealized loss position, number of securities	45	54
Investment securities available for sale in an unrealized loss position, fair value	$ 86,596	$ 139,999
Investment securities available for sale in an unrealized loss position, gross unrealized losses	$ 1,489	$ 2,074
US States and Political Subdivisions Debt Securities [Member]
Note 5 - Investment Securities Available-for-sale (Details) - Reconciliation of Available-for-sale Securities in Continuous Unrealized Loss Position [Line Items]
Investment securities available for sale in an unrealized loss position less than 12 months, number of securities	7	3
Investment securities available for sale in an unrealized loss position less than 12 months, fair value	$ 4,090	$ 1,641
Investment securities available for sale in an unrealized loss position less than 12 months, gross unrealized losses	$ 114	$ 7
Investment securities available for sale in an unrealized loss position 12 months or longer, number of securities		1
Investment securities available for sale in an unrealized loss position 12 months or longer, fair value		$ 1,062
Investment securities available for sale in an unrealized loss position 12 months or longer, gross unrealized losses		$ 10
Investment securities available for sale in an unrealized loss position, number of securities	7	4
Investment securities available for sale in an unrealized loss position, fair value	$ 4,090	$ 2,703
Investment securities available for sale in an unrealized loss position, gross unrealized losses	$ 114	$ 17
Collateralized Mortgage Obligations (Federal Agencies) [Member]
Note 5 - Investment Securities Available-for-sale (Details) - Reconciliation of Available-for-sale Securities in Continuous Unrealized Loss Position [Line Items]
Investment securities available for sale in an unrealized loss position less than 12 months, number of securities	5	11
Investment securities available for sale in an unrealized loss position less than 12 months, fair value	$ 7,544	$ 32,532
Investment securities available for sale in an unrealized loss position less than 12 months, gross unrealized losses	$ 88	$ 192
Investment securities available for sale in an unrealized loss position 12 months or longer, number of securities	9	10
Investment securities available for sale in an unrealized loss position 12 months or longer, fair value	$ 36,461	$ 52,924
Investment securities available for sale in an unrealized loss position 12 months or longer, gross unrealized losses	$ 883	$ 1,358
Investment securities available for sale in an unrealized loss position, number of securities	14	21
Investment securities available for sale in an unrealized loss position, fair value	$ 44,005	$ 85,456
Investment securities available for sale in an unrealized loss position, gross unrealized losses	$ 971	$ 1,550
Other Mortgage-Backed (Federal Agencies) [Member]
Note 5 - Investment Securities Available-for-sale (Details) - Reconciliation of Available-for-sale Securities in Continuous Unrealized Loss Position [Line Items]
Investment securities available for sale in an unrealized loss position less than 12 months, number of securities	6	10
Investment securities available for sale in an unrealized loss position less than 12 months, fair value	$ 6,299	$ 14,889
Investment securities available for sale in an unrealized loss position less than 12 months, gross unrealized losses	$ 72	$ 119
Investment securities available for sale in an unrealized loss position 12 months or longer, number of securities	10	10
Investment securities available for sale in an unrealized loss position 12 months or longer, fair value	$ 17,275	$ 18,979
Investment securities available for sale in an unrealized loss position 12 months or longer, gross unrealized losses	$ 277	$ 321
Investment securities available for sale in an unrealized loss position, number of securities	16	20
Investment securities available for sale in an unrealized loss position, fair value	$ 23,574	$ 33,868
Investment securities available for sale in an unrealized loss position, gross unrealized losses	$ 349	$ 440
SBA Loan-Backed (Federal Agencies) [Member]
Note 5 - Investment Securities Available-for-sale (Details) - Reconciliation of Available-for-sale Securities in Continuous Unrealized Loss Position [Line Items]
Investment securities available for sale in an unrealized loss position less than 12 months, number of securities	3	3
Investment securities available for sale in an unrealized loss position less than 12 months, fair value	$ 5,112	$ 3,122
Investment securities available for sale in an unrealized loss position less than 12 months, gross unrealized losses	$ 12	$ 10
Investment securities available for sale in an unrealized loss position 12 months or longer, number of securities	5	6
Investment securities available for sale in an unrealized loss position 12 months or longer, fair value	$ 9,815	$ 14,850
Investment securities available for sale in an unrealized loss position 12 months or longer, gross unrealized losses	$ 43	$ 57
Investment securities available for sale in an unrealized loss position, number of securities	8	9
Investment securities available for sale in an unrealized loss position, fair value	$ 14,927	$ 17,972
Investment securities available for sale in an unrealized loss position, gross unrealized losses	$ 55	$ 67