Note 16 - Share-Based and Other Compensation Programs Awards Summary (Details) $ in Millions	12 Months Ended
Dec. 31, 2018 USD ($) shares
Equity Compensation Plans
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Maximum contractual term for all awards	10 years
Equity Compensation Plans \| Pro Forma
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Employee Service Share-based Compensation, Nonvested Awards, Acceleration of Compensation Expense \| $	$ 19.7
Equity Compensation Plans \| Grants Awarded From May 13 2009 and Forward \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Change of control, grantee employment termination, vesting period range (in days and years)	90 days
Equity Compensation Plans \| Grants Awarded From May 13 2009 and Forward \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Change of control, grantee employment termination, vesting period range (in days and years)	1 year
Amended and Restated Equity Compensation Plan, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares of common stock authorized for issuance	8,954,109
Number of shares remaining available for grant (shares reserve)	7,906,190
Share-based Compensation Arrangement By Share-based Payment Award Number of Shares Available for Grant Excluding Adjustments	11,108,244
Amended and Restated Equity Compensation Plan, 2017 \| Restricted Stock, Restricted Stock Units and Performance Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation, Reduction of Shares Available for Grant by Each Grant of Equity Award	1.31

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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

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.

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