Note 3 - Accumulated Other Comprehensive Income - Amounts Reclassified Out of Accumulated Other Comprehensive Income by Component (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Net income	$ 4,482	$ 3,556	$ 7,811	$ 9,736
Salaries and employee benefits	(7,646)	(7,655)	(15,263)	(15,634)
Total before tax	6,204	4,791	10,809	13,686
Investment securities (losses) gains, net	(1)	131	(10)	214
Income tax expense	(1,722)	(1,235)	(2,998)	(3,950)
Reclassification out of Accumulated Other Comprehensive Income [Member]
Net income	(2)	76	(58)	121
Reclassification out of Accumulated Other Comprehensive Income [Member] | Accumulated Net Investment Gain (Loss) Attributable to Parent [Member]
Net income	(1)	85	(7)	139
Investment securities (losses) gains, net	(1)	131	(10)	214
Income tax expense		(46)	3	(75)
Reclassification out of Accumulated Other Comprehensive Income [Member] | Accumulated Defined Benefit Plans Adjustment, Net Prior Service Attributable to Parent [Member]
Salaries and employee benefits		(12)	(75)	(25)
Reclassification out of Accumulated Other Comprehensive Income [Member] | Accumulated Defined Benefit Plans Adjustment, Net Gain (Loss) Attributable to Parent [Member]
Salaries and employee benefits	(2)	(2)	(3)	(3)
Reclassification out of Accumulated Other Comprehensive Income [Member] | Accumulated Defined Benefit Plans Adjustment Attributable to Parent [Member]
Net income	(1)	(9)	(51)	(18)
Total before tax	(2)	(14)	(78)	(28)
Income tax expense	$ 1	$ 5	$ 27	$ 10