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.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section S99
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-Subparagraph (SAB Topic 14.F)
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Unrecognized cost of unvested share-based compensation awards.

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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.

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- Definition

The total recognized tax benefit related to compensation cost for equity-based payment arrangements recognized in income during the period.

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Estimated period over which an employee is required to provide service in exchange for the equity-based payment award, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- Definition

The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

+ References

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- Definition

Fair value of share-based awards for which the grantee gained the right by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash.

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- Definition

Number of additional shares authorized for issuance under an established share-based compensation plan.

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No definition available.

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The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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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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Number of fully vested and expected to vest options outstanding that can be converted into shares under option plan. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

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Note 7 - Stock-based Compensation (Details Textual) - USD ($)		3 Months Ended		9 Months Ended		105 Months Ended
	May 31, 2017	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017
Allocated Share-based Compensation Expense		$ 1,100,000		$ 5,200,000	$ 4,700,000
Employee Service Share-based Compensation, Tax Benefit from Compensation Expense		$ 400,000		$ 1,700,000	$ 1,800,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross						0
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Outstanding, Number		1,200		1,200		1,200
Omnibus Plan 2014 [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Additional Shares Authorized	672,000
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant		953,268		953,268		953,268
Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period		0	0	276,900	337,175
Restricted Stock Units (RSUs) [Member] \| Omnibus Plan 2014 [Member]
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized		$ 8,700,000		$ 8,700,000		$ 8,700,000
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized, Period for Recognition				3 years 36 days
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period, Fair Value		14,000	$ 4,000	$ 7,000,000	$ 4,800,000
Phantom Share Units (PSUs) [Member] \| Phantom Stock Plan [Member]
Allocated Share-based Compensation Expense		200,000	400,000	100,000	200,000
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period, Fair Value		$ 200,000	$ 0	$ 200,000	$ 28,000
Share-based Compensation Arrangement by Share-based Payment Award, Award Requisite Service Period				1 year