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Note 11 - Federal Income Taxes (Details) - USD ($) | 12 Months Ended |
--- | --- | ---
Dec. 31, 2015 | Dec. 31, 2014
Note 11 - Federal Income Taxes (Details) [Line Items] |  |
Deferred Tax Assets, Capital Loss Carryforwards | $ 270,000 | $ 450,000
Unrecognized Tax Benefits | 0 | 0
Unrecognized Tax Benefits, Income Tax Penalties and Interest Accrued | 0 | 0
Firstbank Corporation [Member] |  |
Note 11 - Federal Income Taxes (Details) [Line Items] |  |
Deferred Tax Assets, Capital Loss Carryforwards | 300,000 | $ 500,000
Valuation Allowance, Deferred Tax Asset, Increase (Decrease), Amount | (200,000) |
Capital Loss Carryforward [Member] |  |
Note 11 - Federal Income Taxes (Details) [Line Items] |  |
Tax Credit Carryforward, Amount | $ 800,000 |

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- Definition Amount before allocation of valuation allowances of deferred tax asset attributable to deductible capital loss carryforwards. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 6 -URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32621-109319 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 25 -Paragraph 20 -URI http://asc.fasb.org/extlink&oid=51675352&loc=d3e28680-109314 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 8 -URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32632-109319 + Details
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- Definition The amount of the tax credit carryforward, before tax effects, available to reduce future taxable income under enacted tax laws. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 3 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32559-109319 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Carryforwards -URI http://asc.fasb.org/extlink&oid=6506874 + Details
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- Definition Amount of unrecognized tax benefits pertaining to uncertain tax positions taken in tax returns. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 15A -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=6907707&loc=SL6600010-109319 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Unrecognized Tax Benefit -URI http://asc.fasb.org/extlink&oid=6527854 + Details
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- Definition Amount of increase (decrease) in the valuation allowance for a specified deferred tax asset. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 45 -Paragraph 20 -URI http://asc.fasb.org/extlink&oid=37586315&loc=d3e32123-109318 + Details
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