Note 27 - Selected Quarterly Financial Data (Unaudited) - Selected Quarterly Financial Data (Details) - USD ($)
$ / shares in Units, $ in Thousands
 3 Months Ended 12 Months Ended
Dec. 31, 2016
Sep. 30, 2016
Jun. 30, 2016
Mar. 31, 2016
Dec. 31, 2015
Sep. 30, 2015
Jun. 30, 2015
Mar. 31, 2015
Dec. 31, 2016
Dec. 31, 2015
Dec. 31, 2014
Interest income $ 29,922 $ 29,514 $ 29,286 $ 28,269 $ 27,766 $ 27,029 $ 26,993 $ 26,754 $ 116,991 $ 108,542 $ 82,906
Interest expense 2,932 2,797 2,659 2,367 2,337 2,196 1,923 1,959 10,755 8,415 6,078
Net interest income 26,990 26,717 26,627 25,902 25,429 24,833 25,070 24,795 106,236 100,127 76,828
Provision for loan and lease losses 1,059 1,412 445 1,410 1,777 1,200 850 569 4,326 4,396 884
Other income 13,119 13,892 13,820 13,208 13,668 13,350 14,177 14,765      
Other expense 24,958 25,477 26,259 25,051 46,951 25,403 25,982 27,429 13,707 14,498 11,572
Income before income taxes 14,092 13,720 13,743 12,649 (9,631) 11,580 12,415 11,562 54,204 25,926 42,848
Income taxes 4,684 4,346 4,810 4,328 (3,276) 4,084 4,296 4,068 18,168 9,172 15,005
Net Income $ 9,408 $ 9,374 $ 8,933 $ 8,321 $ (6,355) $ 7,496 $ 8,119 $ 7,494 $ 36,036 $ 16,754 $ 27,843
Basic earnings per common share* (in dollars per share) $ 0.56 [1] $ 0.56 [1] $ 0.53 [1] $ 0.49 [1] $ (0.37) [1] $ 0.43 [1] $ 0.46 [1] $ 0.43 [1] $ 2.14 $ 0.96 $ 2.05
Diluted earnings per common share* (in dollars per share) 0.55 [1] 0.55 [1] 0.52 [1] 0.49 [1] (0.37) [1] 0.42 [1] 0.45 [1] 0.42 [1] 2.12 0.94 2.01
Dividends declared per share (in dollars per share) $ 0.21 $ 0.21 $ 0.20 $ 0.20 $ 0.20 $ 0.20 $ 0.19 $ 0.19 $ 0.82 $ 0.78 $ 0.74
[1] Earnings per share is computed independently for each period shown. As a result, the sum of the quarters may not equal the total earnings per share for the year.