Represents the benchmark for the maximum number of shares awarded required for maximum vesting rights.

No definition available.

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- Definition

Represents the benchmark for the minimum number of shares awarded required for minimum vesting rights.

+ References

No definition available.

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- Definition

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

+ References

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
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-SubTopic 10
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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
-Publisher FASB
-Name Accounting Standards Codification
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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.

+ References

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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).

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

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

+ References

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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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Percentage of vesting of share-based compensation awards.

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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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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.

+ References

No definition available.

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Note 12 - Stock-based Compensation (Details Textual) - USD ($) $ in Millions					9 Months Ended	12 Months Ended
	Jun. 06, 2016	May 28, 2015	Jan. 02, 2015	Jun. 01, 2014	Dec. 31, 2014	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized						407,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Intrinsic Value						$ 0.1
First Bank Plans [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross						0	0	0
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Intrinsic Value						$ 1.2
Firstbank Corporation [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross				282,200
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested, Number of Shares				258,400
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Exercisable, Number				23,800
First Bank Employees [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Expiration Period						10 years
Share-based Compensation Arrangement by Share-based Payment Award, Maximum Number of Shares for Maximum Vesting Rights						50
Share-based Compensation Arrangement by Share-based Payment Award, Minimum Number of Shares for Minimum Vesting Rights						50
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage						20.00%
Director [Member]
Stock Issued During Period, Shares, Issued for Services	13,000	14,100	5,994
Allocated Share-based Compensation Expense	$ 0.3	$ 0.3	$ 0.1
Stock Issued for Services Share-based Compensation Expense Period	1 year	1 year	150 days
Maximum [Member]
Employee Service Share-based Compensation, Nonvested Awards, Compensation Not yet Recognized, Stock Options						$ 0.1
Maximum [Member] \| First Bank Employees [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period						5 years
Minimum [Member] \| First Bank Employees [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period						1 year
Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period						3 years	3 years	3 years
Share-based Compensation Arrangement by Share-based Payment Award Accelerated Compensation Cost					$ 0.2
Employee Service Share-based Compensation, Nonvested Awards, Compensation Not yet Recognized, Share-based Awards Other than Options						$ 4.3
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized, Period for Recognition						3 years
Employee Stock Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period						2 years	2 years	2 years
Share-based Compensation Arrangement by Share-based Payment Award, Purchase Price of Common Stock, Percent						110.00%	110.00%	110.00%
Share-based Compensation Arrangement by Share-based Payment Award, Expiration Period						7 years	7 years	7 years