Note 9 - Incentive Plans - Stock Options Activity (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Outstanding balance (in shares)	9,983,727	9,705,495
Outstanding, weighted average exercise price (in dollars per share)	$ 10.19	$ 10.00
Outstanding, remaining term (Year)	7 years 9 months 18 days	8 years 8 months 12 days	9 years 8 months 12 days
Outstanding, intrinsic value	$ 119,781	$ 44,395	$ 57,942
Awards granted (in shares)		442,500
Awards granted, weighted average exercise price (in dollars per share)		$ 14.36
Exercised (in shares)	(7,500)	(154,268)
Exercised, weighted average exercise price (in dollars per share)	$ 10.00	$ 10.00
Forfeitures (in shares)		(10,000)
Forfeitures, weighted average exercise price (in dollars per share)		$ 10.00
Outstanding balance (in shares)	9,976,227	9,983,727	9,705,495
Outstanding, weighted average exercise price (in dollars per share)	$ 10.19	$ 10.19	$ 10.00
Vested (in shares)	8,543,570	8,551,070
Vested, weighted average exercise price (in dollars per share)	$ 10.13	$ 10.13
Vested, remaining term (Year)	7 years 9 months 18 days	8 years 8 months 12 days
Vested, intrinsic value	$ 103,110	$ 38,556
Exercisable (in shares)	8,543,570	8,551,070
Exercisable, weighted average exercise price (in dollars per share)	$ 10.13	$ 10.13
Exercisable, remaining term (Year)	7 years 9 months 18 days	8 years 8 months 12 days
Exercisable, intrinsic value	$ 103,110	$ 38,556

The number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan.

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Gross number of share options (or share units) granted during the period.

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Amount by which the current fair value of the underlying stock exceeds the exercise price of options outstanding.

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

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Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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Amount by which current fair value of underlying stock exceeds exercise price of fully vested and expected to vest exercisable or convertible options. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

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Number of fully vested and expected to vest exercisable options that may be converted into shares under option plan. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

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Weighted-average exercise price, at which grantee can acquire shares reserved for issuance, for fully vested and expected to vest exercisable or convertible options. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

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Amount by which current fair value of underlying stock exceeds exercise price of fully vested and expected to vest options outstanding. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

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Number of fully vested and expected to vest options outstanding that can be converted into shares under option plan. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

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Weighted-average exercise price, at which grantee can acquire shares reserved for issuance, for fully vested and expected to vest options outstanding. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

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

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Weighted average price at which grantees could have acquired the underlying shares with respect to stock options that were terminated.

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Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options.

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Weighted average remaining contractual term for vested portions of options outstanding and currently exercisable or convertible, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Weighted average remaining contractual term for option awards outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Weighted average remaining contractual term for fully vested and expected to vest options outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

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

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