Note 2 - Business Combination (Details) - Pro Forma Information (Firstbank Corporation [Member], USD $)	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013
Firstbank Corporation [Member]
Note 2 - Business Combination (Details) - Pro Forma Information [Line Items]
Net interest income	$ 98,607,000	$ 93,862,000
Noninterest expense	81,295,000	93,263,000
Net income	$ 22,659,000	$ 16,068,000
Net income per diluted share (in Dollars per share)	$ 1.33	$ 0.96

The pro forma net interest Income or Loss for the period as if the business combination or combinations had been completed at the beginning of a period.

No definition available.

+ Details

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- Definition

The pro forma noninterest expense for the period as if the business combination or combinations had been completed at the beginning of a period.

+ References

No definition available.

+ Details

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- Definition

The pro forma diluted net income per share for a period as if the business combination or combinations had been completed at the beginning of a period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 805

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (h)(2)-(3)

-URI http://asc.fasb.org/extlink&oid=25497992&loc=d3e1392-128463

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- Definition

The pro forma net Income or Loss for the period as if the business combination or combinations had been completed at the beginning of a period.

+ References

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