Additional retainer amount paid each year to non-employee director under Director Compensation Program.

No definition available.

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- Definition

Retainer amount paid each year to non-employee director under Director Compensation Program.

+ References

No definition available.

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- Definition

Represents the Maximum number of shares authorized for the incentive stock options for the equity based compensation plan.

+ References

No definition available.

+ Details

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- Definition

Number of equity instruments other than options that are vested and deferred as of the balance sheet date.

+ References

No definition available.

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- Definition

The number of installments in which an employee award vests.

+ References

No definition available.

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- Definition

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
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 14.F)
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- Definition

Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from share-based compensation.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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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
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (i)
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- Definition

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

+ References

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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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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-Paragraph 2
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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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- 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).

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-Section 50
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- Definition

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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-Publisher FASB
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Note 8 - Equity-based Compensation (Details Textual)	3 Months Ended
Note 8 - Equity-based Compensation (Details Textual)	Mar. 31, 2017 USD ($) shares	Mar. 31, 2016 USD ($)	Jun. 05, 2015 shares
Allocated Share-based Compensation Expense	$ 2,400,000	$ 3,000,000
Employee Service Share-based Compensation, Tax Benefit from Compensation Expense	3,500,000
Deferred Tax Assets, Tax Deferred Expense, Compensation and Benefits, Share-based Compensation Cost	$ 5,700,000
Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangements by Share-based Payment Award, Vesting Period, Number of Installments	4
Annual Retainer	$ 150,000
Additional Annual Retainer	15,000
Allocated Share-based Compensation Expense	1,700,000
Employee Service Share-based Compensation, Nonvested Awards, Compensation Not yet Recognized, Share-based Awards Other than Options	$ 11,000,000
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized, Period for Recognition	1 year 146 days
Restricted Stock Units (RSUs) [Member] \| Non-employee Directors [Member
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period	1 year
Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Vested and Deferred, Number \| shares	2,210
Stock Appreciation Rights (SARs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period	4 years
Share-based Compensation Arrangements by Share-based Payment Award, Vesting Period, Number of Installments	4
Allocated Share-based Compensation Expense	$ 700,000
Employee Service Share-based Compensation, Nonvested Awards, Compensation Not yet Recognized, Share-based Awards Other than Options	$ 9,700,000
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized, Period for Recognition	1 year 109 days
The 2015 Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant \| shares	329,962
The 2015 Plan [Member] \| Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period	3 years
Maximum [Member] \| The 2015 Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized \| shares			600,000
Share-based Compensation Arrangement by Share-based Payment Award, Maximum Number of Shares Authorized for Incentive Stock Options \| shares			400,000