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.

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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.

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- Definition

The number of installments in which an employee award vests.

+ References

No definition available.

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- Definition

Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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- Definition

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

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- Definition

Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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- Definition

Amount of cost to be recognized for nonvested award under share-based payment arrangement. Excludes share and unit options.

+ References

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- Definition

Amount of tax benefit for recognition of expense of award under share-based payment arrangement.

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Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

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- Definition

Number of shares authorized for issuance under share-based payment arrangement.

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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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Note 14 - Equity-based Compensation (Details Textual)	12 Months Ended
Note 14 - Equity-based Compensation (Details Textual)	Dec. 31, 2019 USD ($) shares	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)	Jun. 05, 2015 shares
Share-based Payment Arrangement, Expense, Tax Benefit	$ 5,300,000
Deferred Tax Assets, Tax Deferred Expense, Compensation and Benefits, Share-based Compensation Cost	4,563,000	$ 4,080,000
Restricted Stock Units (RSUs) [Member]
Share-based Payment Arrangement, Expense	$ 8,000,000.0	6,800,000	$ 7,500,000
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period	3 years
Share-based Compensation Arrangements by Share-based Payment Award, Vesting Period, Number of Installments	4
Annual Retainer	$ 75,000
Additional Annual Retainer	125,000
Share-based Payment Arrangement, Nonvested Award, Excluding Option, Cost Not yet Recognized, Amount	$ 10,900,000
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition	1 year
Restricted Stock Units (RSUs) [Member] \| Non-employee Directors [Member
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period	1 year
Stock Appreciation Rights (SARs) [Member]
Share-based Payment Arrangement, Expense	$ 4,300,000	3,700,000	3,300,000
Share-based Compensation Arrangements by Share-based Payment Award, Vesting Period, Number of Installments	4
Share-based Payment Arrangement, Nonvested Award, Excluding Option, Cost Not yet Recognized, Amount	$ 7,600,000
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition	1 year 3 months 18 days
Selling, General and Administrative Expenses [Member]
Share-based Payment Arrangement, Expense	$ 12,300,000	$ 10,500,000	$ 10,700,000
The 2015 Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized \| shares				334,870
Share-based Compensation Arrangement by Share-based Payment Award, Maximum Number of Shares Authorized for Incentive Stock Options \| shares				329,962
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant \| shares	169,456