Note 2 - Business Combination (Details) - Pro Forma Information (Firstbank Corporation [Member], USD $)	3 Months Ended	6 Months Ended
Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Firstbank Corporation [Member]
Note 2 - Business Combination (Details) - Pro Forma Information [Line Items]
Net interest income	$ 15,453,000	$ 11,212,000	$ 26,417,000	$ 22,566,000
Noninterest expense	17,160,000	13,407,000	26,862,000	22,786,000
Net income	$ 863,000	$ 900,000	$ 4,186,000	$ 5,043,000
Net income per diluted share (in Dollars per share)	$ 0.05	$ 0.05	$ 0.25	$ 0.30

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.

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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.

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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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