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Represents the period over which share-based compensation related to shares issued for service was expensed.

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No definition available.

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Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
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-Publisher FASB
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-Publisher FASB
-Name Accounting Standards Codification
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-Paragraph 2
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Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Staff Accounting Bulletin (SAB)
-Number Topic 14
-Section F

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- Definition

Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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-SubTopic 10
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-Paragraph 2
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- Definition

Unrecognized cost of unvested share-based awards, other than options, awarded to employees as compensation.

+ References

No definition available.

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- Definition

Unrecognized cost of unvested options awarded to employees as compensation.

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No definition available.

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- Definition

Additional share-based compensation cost recognized as a result of an occurrence of an event that accelerates its recognition.

+ References

No definition available.

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- Definition

Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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

The maximum number of shares (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units remain authorized and become reserved for issuance under outstanding awards (not necessarily vested).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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- Definition

Gross number of share options (or share units) granted during the period.

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No definition available.

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- Definition

The number of exercisable share options (fully vested and expected to vest) that may be converted as of the balance sheet date.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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- Definition

Percentage of vesting of share-based compensation awards.

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

Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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

Amount of difference between fair value of the underlying shares reserved for issuance and exercise price of vested portions of options outstanding and currently exercisable.

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

Number of options vested.

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No definition available.

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- Definition

Purchase price of common stock expressed as a percentage of its fair value.

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No definition available.

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- Definition

Number of shares issued in lieu of cash for services contributed to the entity. Number of shares includes, but is not limited to, shares issued for services contributed by vendors and founders.

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No definition available.

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Note 12 - Stock-based Compensation (Details) - USD ($)				3 Months Ended	12 Months Ended
Note 12 - Stock-based Compensation (Details) - USD ($)	May. 28, 2015	Jan. 02, 2015	Jun. 01, 2014	Jun. 30, 2014	Dec. 31, 2015	Dec. 31, 2014
Note 12 - Stock-based Compensation (Details) [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized (in Shares)					215,000
Stock Issued During Period, Shares, Issued for Services (in Shares)	14,100
Allocated Share-based Compensation Expense (in Dollars)	$ 300,000
Stock Issued For Services Share-based Compensation Expense Period	12 months
Director [Member]
Note 12 - Stock-based Compensation (Details) [Line Items]
Stock Issued During Period, Shares, Issued for Services (in Shares)		5,994
Allocated Share-based Compensation Expense (in Dollars)		$ 100,000
Stock Issued For Services Share-based Compensation Expense Period		5 months
Firstbank Plans [Member]
Note 12 - Stock-based Compensation (Details) [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross (in Shares)					0	0
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Intrinsic Value (in Dollars)					$ 1,500,000
Firstbank Corporation [Member]
Note 12 - Stock-based Compensation (Details) [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross (in Shares)			282,200
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Exercisable, Number (in Shares)			258,400
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested, Number of Shares (in Shares)					23,800
Options Granted During 2006, 2007 And 2008 [Member]
Note 12 - Stock-based Compensation (Details) [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period					2 years
Share-based Compensation Arrangement by Share-based Payment Award, Expiration Period					7 years
Restricted Stock Granted In 2012 [Member]
Note 12 - Stock-based Compensation (Details) [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period					2 years
Restricted Stock Granted In 2014 And 2015 [Member]
Note 12 - Stock-based Compensation (Details) [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period					3 years
Stock Options Granted During 2014 And 2015 [Member]
Note 12 - Stock-based Compensation (Details) [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period					2 years
Share-based Compensation Arrangement by Share-based Payment Award, Expiration Period					7 years
Share-based Compensation Arrangement by Share-based Payment Award, Purchase Price of Common Stock, Percent					110.00%
Restricted Stock [Member]
Note 12 - Stock-based Compensation (Details) [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award Accelerated Compensation Cost (in Dollars)				$ 200,000
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized, Period for Recognition					3 years
Employee Service Share-based Compensation, Nonvested Awards, Compensation Not yet Recognized, Share-based Awards Other than Options (in Dollars)					$ 3,000,000
Employee Stock Option [Member]
Note 12 - Stock-based Compensation (Details) [Line Items]
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized, Period for Recognition					2 years
Employee Stock Option [Member] \| Firstbank Corporation [Member]
Note 12 - Stock-based Compensation (Details) [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Expiration Period					10 years
Stock Option Grants For 50 Shares Or Less [Member] \| Firstbank Corporation [Member]
Note 12 - Stock-based Compensation (Details) [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period					1 year
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage					20.00%
Maximum [Member]
Note 12 - Stock-based Compensation (Details) [Line Items]
Employee Service Share-based Compensation, Nonvested Awards, Compensation Not yet Recognized, Stock Options (in Dollars)					$ 100,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Intrinsic Value (in Dollars)					$ 0