Represents credit facility consolidated leverage ratio for 20 million share repurchases.

No definition available.

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Represents the credit facility consolidated leverage ratio for unlimited share repurchases.

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No definition available.

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Represents credit facility consolidated leverage ratio For zero Share repurchases.

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No definition available.

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

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- Definition

Amount of cost not yet recognized for nonvested award under share-based payment arrangement.

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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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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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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

Number of options outstanding, including both vested and non-vested options.

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- Definition

Weighted average price at which option holders acquired shares when converting their stock options into shares.

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No definition available.

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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

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Number of share options (or share units) exercised during the current period.

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Amount of stock repurchase plan authorized.

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No definition available.

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The number of shares authorized to be repurchased by an entity's Board of Directors under a stock repurchase plan.

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No definition available.

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The remaining number of shares authorized to be repurchased by an entity's Board of Directors under a stock repurchase plan.

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No definition available.

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Number of shares that have been repurchased during the period and have not been retired and are not held in treasury. Some state laws may govern the circumstances under which an entity may acquire its own stock and prescribe the accounting treatment therefore. This element is used when state law does not recognize treasury stock.

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Equity impact of the value of stock that has been repurchased during the period and has not been retired and is not held in treasury. Some state laws may mandate the circumstances under which an entity may acquire its own stock and prescribe the accounting treatment therefore. This element is used when state law does not recognize treasury stock.

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Total cost of shares repurchased divided by the total number of shares repurchased.

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Note 9 - Stockholders' Equity and Equity Compensation (Details Textual) $ / shares in Units, $ in Millions	3 Months Ended			9 Months Ended
	Sep. 30, 2020 USD ($) shares	Sep. 30, 2019 USD ($)	Mar. 31, 2019 $ / shares shares	Sep. 30, 2020 USD ($) $ / shares shares	Sep. 30, 2019 USD ($) $ / shares shares	Jun. 30, 2020 USD ($)	Apr. 29, 2020 USD ($)	Dec. 31, 2019 shares	Apr. 30, 2019 shares	Dec. 31, 2018 shares	Apr. 30, 2018 shares
Stock Repurchase Program, Authorized Amount \| $							$ 5.0
Share-based Compensation Arrangement by Share-based Payment Award, Award Requisite Service Period (Year)				1 year
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period (in shares)			52,783
Share-based Compensation Arrangements by Share-based Payment Award, Options, Exercises in Period, Weighted Average Exercise Price (in dollars per share) \| $ / shares			$ 18.11
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number, Ending Balance (in shares)	0			0				0
A 2016 Employee Plan [Member]
Stock Repurchase Program, Number of Shares Authorized to be Repurchased (in shares)											1,700,000
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant (in shares)	1,355,403			1,355,403
A 2016 Director Plan [Member]
Stock Repurchase Program, Number of Shares Authorized to be Repurchased (in shares)									300,000
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant (in shares)	254,350			254,350
Share-based Payment Arrangement, Option [Member]
Stock Repurchased During Period, Shares (in shares)					48,409
Stock Repurchased During Period, Value \| $					$ 1.0
Treasury Stock Acquired, Average Cost Per Share (in dollars per share) \| $ / shares					$ 20.52
Current Stock Awards [Member]
Share-based Payment Arrangement, Expense \| $	$ 3.4	$ 1.5		$ 7.4	$ 5.5
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount, Total \| $	12.7			$ 12.7
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition (Year)				1 year 11 months 15 days
Deferred Stock Units [Member]
Share-based Payment Arrangement, Expense \| $	0.3	$ 0.3		$ 0.7	$ 0.3
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount, Total \| $	$ 0.5			$ 0.5
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition (Year)				7 months 6 days
Maximum [Member] \| Share-based Payment Arrangement, Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Expiration Period (Year)				10 years
Minimum [Member] \| Share-based Payment Arrangement, Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Expiration Period (Year)				7 years
A 2015 Credit Facility [Member] \| Revolving Credit Facility [Member] \| Maximum [Member]
Credit Facility Consolidated Leverage Ratio for Unlimited Share Repurchases							2.50
Credit Facility Consolidated Leverage Ratio for 20 Million Share Repurchases							3.00
A 2015 Credit Facility [Member] \| Revolving Credit Facility [Member] \| Minimum [Member]
Credit Facility Consolidated Leverage Ratio for 20 Million Share Repurchases							2.50
Credit Facility Consolidated Leverage Ratio for Zero Share Repurchases							3.00
The 2019 Program [Member]
Stock Repurchase Program, Number of Shares Authorized to be Repurchased (in shares)								2,000,000
The 2018 Program [Member]
Stock Repurchase Program, Number of Shares Authorized to be Repurchased (in shares)										2,000,000
Stock Repurchase Program, Remaining Number of Shares Authorized to be Repurchased (in shares)	327,161			327,161
In Connection With Equity Compensation Programs [Member]
Stock Repurchase Program, Authorized Amount \| $						$ 10.0
Stock Repurchased During Period, Shares (in shares)				93,386	110,406
Stock Repurchased During Period, Value \| $				$ 2.0	$ 2.2
Treasury Stock Acquired, Average Cost Per Share (in dollars per share) \| $ / shares				$ 21.83	$ 20.21
Through The Open Market Repurchase Program [Member]
Stock Repurchased During Period, Shares (in shares)				180,491	1,426,916
Stock Repurchased During Period, Value \| $				$ 3.2	$ 24.9
Treasury Stock Acquired, Average Cost Per Share (in dollars per share) \| $ / shares				$ 17.80	$ 17.46