Note 8 - Federal Home Loan Bank Advances (Details) (USD $)			9 Months Ended
Sep. 30, 2014	Dec. 31, 2013	Sep. 30, 2014 Firstbank Corporation [Member]
Note 8 - Federal Home Loan Bank Advances (Details) [Line Items]
Long-term Federal Home Loan Bank Advances (in Dollars)	$ 57,033,000	$ 45,000,000
Federal Home Loan Bank, Advances, General Debt Obligations, Disclosures, Interest Rate, Range from	0.41%	1.22%
Federal Home Loan Bank, Advances, General Debt Obligations, Disclosures, Interest Rate, Range to	1.51%	1.51%
Federal Home Loan Bank, Advances, Branch of FHLB Bank, Weighted Average Interest Rate	1.21%	1.34%
Increase in Federal Home Loan Bank Advances (in Dollars)			12,000,000
Line of Credit Facility, Maximum Borrowing Capacity (in Dollars)	570,000,000
Line of Credit Facility, Remaining Borrowing Capacity (in Dollars)	$ 511,000,000

The increase during the period in Federal Home Loan Bank advances.

No definition available.

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- Definition

Describes the weighted average interest rate applicable to the specific advances from the Federal Home Loan Bank, by branch, as of the Balance Sheet date.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 470

-Section 45

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6479118&loc=d3e64650-112822

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-Publisher FASB

-Name Accounting Standards Codification

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-SubTopic 470

-Section 50

-Paragraph 3

-Subparagraph (b)

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.19(b))

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- Definition

States the lowest interest rate applicable to any of the advances from the Federal Home Loan Bank as of the Balance Sheet date.

+ References

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States the highest interest rate applicable to any of the advances from the Federal Home Loan Bank as of the Balance Sheet date.

+ References

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Including both current and noncurrent portions, Federal Home Loan Bank borrowings initially due beyond one year or beyond the normal operating cycle if longer.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 470

-Section 45

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6479118&loc=d3e64650-112822

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

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-Article 9

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- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.19(b),22(b))

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 19, 22

-Article 5

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Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

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