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Note 2 - Business Combination (Details) - Pro Forma Information - Jun. 30, 2014 - USD ($) | Total | Total
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Note 2 - Business Combination (Details) - Pro Forma Information [Line Items] |  |
Net interest income |  | $ 47,934,000
Noninterest expense |  | 39,716,000
Net income |  | $ 11,965,000
Net income per diluted share (in Dollars per share) |  | $ 0.71
Firstbank Corporation [Member] |  |
Note 2 - Business Combination (Details) - Pro Forma Information [Line Items] |  |
Net interest income | $ 24,051,000 |
Noninterest expense | 19,698,000 |
Net income | $ 5,708,000 |
Net income per diluted share (in Dollars per share) | $ 0.34 |

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