Note 17 - Share-Based Compensation and Other Benefit Programs - Awards Summary (Details)	12 Months Ended
Dec. 31, 2020 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 \| 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 \| 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 remaining available for grant (shares reserve)	3,478,075
Share-based Compensation Arrangement By Share-based Payment Award Number of Shares Available for Grant Excluding Adjustments	8,050,843
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

Change of Control, Grantee Employment Termination, Vesting Period Range

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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 number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan without adjustment for ratio of shares beyond 1 for 1 (reserve adjustment).

+ References

No definition available.

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- Definition

Represents the multiplier to use against issued shares to determine number of shares still available for grant for equity settled awards (RSUs, Restricted Stock, or other performance share awards).

+ References

No definition available.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901

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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

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
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