Note 11 - Share-based Compensation - Summary of RSU Activity (Details) - Restricted Stock Units (RSUs) [Member]	9 Months Ended
Sep. 30, 2021 $ / shares shares
Awards other than options, unvested, beginning balance (in shares) \| shares	428,006
Awards other than options, unvested, weighted average grant date fair value, beginning balance (in dollars per share) \| $ / shares	$ 6.13
Awards other than options, Granted - service based (in shares) \| shares	352,890
Awards other than options, granted - service based, weighted average grant date fair value (in dollars per share) \| $ / shares	$ 5.72
Awards other than options, Vested (in shares) \| shares	(421,407)
Awards other than options, vested, weighted average grant date fair value (in dollars per share) \| $ / shares	$ 5.63
Awards other than options, Forfeited and cancelled (in shares) \| shares	(32,874)
Awards other than options, forfeited and cancelled, weighted average grant date fair value (in dollars per share) \| $ / shares	$ 6.10
Awards other than options, unvested, ending balance (in shares) \| shares	326,615
Awards other than options, unvested, weighted average grant date fair value, ending balance (in dollars per share) \| $ / shares	$ 6.34
Weighted average vesting period (Year)	2 years 1 month 6 days

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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The number of equity-based payment instruments, excluding stock (or unit) options, that were forfeited during the reporting period.

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Weighted average fair value as of the grant date of equity-based award plans other than stock (unit) option plans that were not exercised or put into effect as a result of the occurrence of a terminating event.

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The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

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Per share or unit weighted-average fair value of nonvested award under share-based payment arrangement. Excludes share and unit options.

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The weighted average fair value as of grant date pertaining to an equity-based award plan other than a stock (or unit) option plan for which the grantee gained the right during the reporting period, by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash in accordance with the terms of the arrangement.

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