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Note 9 - Stock-Based Compensation - Schedule of Share-Based Payment Award (Details) - $ / shares | 12 Months Ended
--- | ---
Dec. 31, 2022 | Dec. 31, 2021
Balance, outstanding (in shares) | 3,763,000 |
Balance, Weighted-Average Exercise Price (in dollars per share) | $ 2.29 |
Balance, outstanding (in shares) | 4,694,000 | 3,763,000
Balance, Weighted-Average Exercise Price (in dollars per share) | $ 4.63 | $ 2.29
The 2019 Stock Plan [Member] |  |
Balance, Shares Available for Grant (in shares) | 142,000 | 380,000
Balance, outstanding (in shares) | 3,763,000 | 5,327,000
Balance, Weighted-Average Exercise Price (in dollars per share) | $ 2.29 | $ 1.14
Authorized, shares (in shares) | 1,338,000 | 816,000
Options Granted, shares (in shares) | (1,307,000) | (1,141,000)
Options Granted, shares (in shares) | 1,307,000 | 1,141,000
Options Granted, Weighted-Average Exercise Price (in dollars per share) | $ 10.97 | $ 5.60
Exercised, outstanding (in shares) | (295,000) | (2,498,000)
Exercised, Weighted-Average Exercise Price (in dollars per share) | $ 0.93 | $ 1.39
Forfeited/expired, shares available (in shares) | 81,000 | 241,000
Forfeited/expired, outstanding (in shares) | (81,000) | (207,000)
Forfeited/expired, Weighted-Average Exercise Price (in dollars per share) | $ 11.63 | $ 1.84
Balance, Shares Available for Grant (in shares) | 165,000 | 142,000
Balance, outstanding (in shares) | 4,694,000 | 3,763,000
Balance, Weighted-Average Exercise Price (in dollars per share) | $ 4.63 | $ 2.29
The 2019 Stock Plan [Member] | Restricted Stock [Member] |  |
RSAs Granted, shares (in shares) | (89,000) | (154,000)

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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). + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(2)(iii)(01) -URI https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901 + Details
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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 https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901 + Details
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- Definition For presentations that combine terminations, 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 or that expired. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(1)(iv) -URI https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901 + Details
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- Definition Weighted average price of options that were either forfeited or expired. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(1)(iv) -URI https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901 + Details
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- Definition Gross number of share options (or share units) granted during the period. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(1)(iv)(01) -URI https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901 + Details
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- Definition Number of options outstanding, including both vested and non-vested options. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(1)(ii) -URI https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(1)(i) -URI https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901 + Details
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