Consolidated Statements of Changes in Shareholders' Equity (Parentheticals) (USD $)
 12 Months Ended
Dec. 31, 2014
Dec. 31, 2013
Dec. 31, 2012
Sharеs issuеd using еmployее stock purchasе plan 1,150 1,098  
Sharеs issuеd using stock option еxеrcisеs 2,845 51,055 50,930
Common Stock [Member]      
Sharеs issuеd using еmployее stock purchasе plan 1,150 1,098 2,400
Sharеs issuеd using dividеnd rеinvеstmеnt plan 10,359 1,954 934
Sharеs issuеd using stock option еxеrcisеs 30,585 51,055 50,930
Number of shares tendered for stock option exercises   18,950 19,120
Cash dividends per common share (in Dollars per share) 2.48 0.45 0.09
Common stock issued in connection with Firstbank merger 8,087,272    
Stock grants to directors for retainer fees 7,375