v3.23.2

Note 15 - Stock-based Compensation - Stock Options Outstanding, Vested and Exercisable (Details) - $ / shares | 12 Months Ended |
--- | --- | ---
Dec. 31, 2022 | Dec. 31, 2021
Exercise Price Range, Upper Range Limit (in dollars per share) |  |
Number of Stock Options Outstanding (in shares) | 725,623 | 714,085
Weighted-average Remaining Contractual LIfe (Year) | 5 years 3 months 18 days |
Options Outstanding, Weighted-average Exercise Price Per Share (in dollars per share) | $ 52.98 | $ 59.79
Shares Subject to Stock Options (in shares) | 515,933 |
Options Vested and Exercisable, Weighted-average Exercise Price Per Share (in dollars per share) | $ 65.76 |
Exercise Price Range 1 [Member] |  |
Exercise Price Range, Lower Range Limit (in dollars per share) | 4.62 |
Exercise Price Range, Upper Range Limit (in dollars per share) | $ 8.03 |
Number of Stock Options Outstanding (in shares) | 88,096 |
Weighted-average Remaining Contractual LIfe (Year) | 9 years 2 months 12 days |
Options Outstanding, Weighted-average Exercise Price Per Share (in dollars per share) | $ 7.54 |
Shares Subject to Stock Options (in shares) | 0 |
Options Vested and Exercisable, Weighted-average Exercise Price Per Share (in dollars per share) | $ 0 |
Exercise Price Range 2 [Member] |  |
Exercise Price Range, Lower Range Limit (in dollars per share) | 8.36 |
Exercise Price Range, Upper Range Limit (in dollars per share) | $ 12.54 |
Number of Stock Options Outstanding (in shares) | 19,046 |
Weighted-average Remaining Contractual LIfe (Year) | 9 years 1 month 6 days |
Options Outstanding, Weighted-average Exercise Price Per Share (in dollars per share) | $ 8.43 |
Shares Subject to Stock Options (in shares) | 0 |
Options Vested and Exercisable, Weighted-average Exercise Price Per Share (in dollars per share) | $ 0 |
Exercise Price Range 3 [Member] |  |
Exercise Price Range, Lower Range Limit (in dollars per share) | 14.40 |
Exercise Price Range, Upper Range Limit (in dollars per share) | $ 21.60 |
Number of Stock Options Outstanding (in shares) | 20,941 |
Weighted-average Remaining Contractual LIfe (Year) | 6 years 10 months 24 days |
Options Outstanding, Weighted-average Exercise Price Per Share (in dollars per share) | $ 16.93 |
Shares Subject to Stock Options (in shares) | 13,643 |
Options Vested and Exercisable, Weighted-average Exercise Price Per Share (in dollars per share) | $ 16.84 |
Exercise Price Range 4 [Member] |  |
Exercise Price Range, Lower Range Limit (in dollars per share) | 22.40 |
Exercise Price Range, Upper Range Limit (in dollars per share) | $ 33.60 |
Number of Stock Options Outstanding (in shares) | 11,700 |
Weighted-average Remaining Contractual LIfe (Year) | 8 years 1 month 6 days |
Options Outstanding, Weighted-average Exercise Price Per Share (in dollars per share) | $ 28.62 |
Shares Subject to Stock Options (in shares) | 10,774 |
Options Vested and Exercisable, Weighted-average Exercise Price Per Share (in dollars per share) | $ 28.58 |
Exercise Price Range 5 [Member] |  |
Exercise Price Range, Lower Range Limit (in dollars per share) | 34.40 |
Exercise Price Range, Upper Range Limit (in dollars per share) | $ 51.60 |
Number of Stock Options Outstanding (in shares) | 311,695 |
Weighted-average Remaining Contractual LIfe (Year) | 6 years |
Options Outstanding, Weighted-average Exercise Price Per Share (in dollars per share) | $ 41.16 |
Shares Subject to Stock Options (in shares) | 217,425 |
Options Vested and Exercisable, Weighted-average Exercise Price Per Share (in dollars per share) | $ 42.75 |
Exercise Price Range 6 [Member] |  |
Exercise Price Range, Lower Range Limit (in dollars per share) | 52.00 |
Exercise Price Range, Upper Range Limit (in dollars per share) | $ 78.00 |
Number of Stock Options Outstanding (in shares) | 168,275 |
Weighted-average Remaining Contractual LIfe (Year) | 3 years 6 months |
Options Outstanding, Weighted-average Exercise Price Per Share (in dollars per share) | $ 62.66 |
Shares Subject to Stock Options (in shares) | 168,221 |
Options Vested and Exercisable, Weighted-average Exercise Price Per Share (in dollars per share) | $ 62.66 |
Exercise Price Range 7 [Member] |  |
Exercise Price Range, Lower Range Limit (in dollars per share) | 78.40 |
Exercise Price Range, Upper Range Limit (in dollars per share) | $ 117.60 |
Number of Stock Options Outstanding (in shares) | 62,756 |
Weighted-average Remaining Contractual LIfe (Year) | 1 year |
Options Outstanding, Weighted-average Exercise Price Per Share (in dollars per share) | $ 97.95 |
Shares Subject to Stock Options (in shares) | 62,756 |
Options Vested and Exercisable, Weighted-average Exercise Price Per Share (in dollars per share) | $ 97.95 |
Exercise Price Range 8 [Member] |  |
Exercise Price Range, Lower Range Limit (in dollars per share) | 132.00 |
Exercise Price Range, Upper Range Limit (in dollars per share) | $ 198.00 |
Number of Stock Options Outstanding (in shares) | 20,520 |
Weighted-average Remaining Contractual LIfe (Year) | 1 year 7 months 6 days |
Options Outstanding, Weighted-average Exercise Price Per Share (in dollars per share) | $ 133.16 |
Shares Subject to Stock Options (in shares) | 20,520 |
Options Vested and Exercisable, Weighted-average Exercise Price Per Share (in dollars per share) | $ 133.16 |
Exercise Price Range 9 [Member] |  |
Exercise Price Range, Lower Range Limit (in dollars per share) | 204.40 |
Exercise Price Range, Upper Range Limit (in dollars per share) | $ 306.60 |
Number of Stock Options Outstanding (in shares) | 22,594 |
Weighted-average Remaining Contractual LIfe (Year) | 1 year |
Options Outstanding, Weighted-average Exercise Price Per Share (in dollars per share) | $ 206.96 |
Shares Subject to Stock Options (in shares) | 22,594 |
Options Vested and Exercisable, Weighted-average Exercise Price Per Share (in dollars per share) | $ 206.96 |

X
- Definition The weighted average exercise price of exercisable share options (fully vested and expected to vest) that may be converted as of the balance sheet date. + References No definition available. + 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 -Topic 718 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (c)(1)(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)(1)(ii) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480429/718-10-50-2 + Details
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- Definition Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 718 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (c)(1)(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)(1)(ii) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480429/718-10-50-2 + Details
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- Definition 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. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 718 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (e)(2) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480429/718-10-50-2 + Details
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