Note 8 - Stock-based Compensation - Summary of RSU Activity (Details) - Restricted Stock Units (RSUs) [Member] - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	6 Months Ended
Jun. 30, 2023	Dec. 31, 2022
Unvested, shares (in shares)	900
Unvested, weighted average price per share (in dollars per share)	$ 3.83
Unvested, weighted average fair value	$ 6,984	$ 3,447
Granted, shares (in shares)	900
Granted, weighted average price per share (in dollars per share)	$ 3.93
Granted, weighted average fair value	$ 3,537
Vested, shares (in shares)	0
Vested, weighted average price per share (in dollars per share)	$ 0
Forfeited or canceled, shares (in shares)	0
Forfeited or canceled, weighted average price per share (in dollars per share)	$ 0
Unvested, shares (in shares)	1,800
Unvested, weighted average price per share (in dollars per share)	$ 3.88

Intrinsic value of granted award under share-based payment arrangement. Excludes share and unit options.

No definition available.

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- Definition

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

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- Definition

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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- Definition

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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- Definition

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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- Definition

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.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (c)(2)(i)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480429/718-10-50-2

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (c)(2)(ii)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480429/718-10-50-2

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- Definition

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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- Definition

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

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- Definition

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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- Definition

Intrinsic value of nonvested award under share-based payment arrangement. Excludes share and unit options.

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No definition available.

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