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Consolidated Statements of Changes in Shareholders' Equity (Parentheticals) - $ / shares | 12 Months Ended
--- | ---
Dec. 31, 2015 | Dec. 31, 2014 | Dec. 31, 2013
Employee stock purchase plan, shares | 2,058 | 1,150 |
Common Stock [Member] |  |  |
Employee stock purchase plan, shares | 2,058 | 1,150 | 1,098
Dividend reinvestment plan, shares | 30,467 | 10,359 | 1,954
Stock option exercises, shares | 59,117 | 30,585 | 51,055
Stock tendered for stock option exercises, shares |  |  | 18,950
Cash dividends per common share (in Dollars per share) | $ 0.58 | $ 2.48 | $ 0.45
Common stock issued in connection with Firstbank merger |  | 8,087,272 |
Stock grants to directors for retainer fees | 20,094 | 7,375 |
Share repurchase program | 788,541 |  |

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