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Stock-Based Awards - Option Activity (Details) - USD ($) $ / shares in Units, $ in Thousands | 9 Months Ended | 12 Months Ended
--- | --- | ---
Sep. 30, 2025 | Dec. 31, 2024
Options, Number of Shares |  |
Number of Shares, beginning balance | 6,721,967 |
Number of Shares, Granted | 5,194,155 |
Number of Shares, Forfeited and cancelled | (461,604) |
Number of Shares, ending balance | 11,454,518 | 6,721,967
Number of Shares, Options vested and expected to vest | 11,454,518 |
Number of Shares, Options exercisable | 4,358,272 |
Options, Weighted Average Exercise Price |  |
Weighted Average Exercise Price, beginning balance (in dollars per share) | $ 11.12 |
Weighted Average Exercise Price, Granted (in dollars per share) | 2.16 |
Weighted Average Exercise Price, Forfeited and cancelled (in dollars per share) | 7.34 |
Weighted Average Exercise Price, ending balance (in dollars per share) | 7.27 | $ 11.12
Weighted Average Exercise Price, Options vested and expected to vest (in dollars per share) | 7.27 |
Weighted Average Exercise Price, Options exercisable (in dollars per share) | $ 13.75 |
Options, Weighted Average Remaining Contractual Term |  |
Weighted Average Remaining Contractual Term (in years) | 7 years 9 months 18 days | 6 years 9 months 18 days
Weighted Average Remaining Contractual Term, Options vested and expected to vest (in years) | 7 years 9 months 18 days |
Weighted Average Remaining Contractual Term, Options exercisable (in years) | 5 years 8 months 12 days |
Aggregate Intrinsic Value |  |
Aggregate Intrinsic Value | $ 2,157 | $ 2,968
Aggregate Intrinsic Value, Options vested and expected to vest | 2,157 |
Aggregate Intrinsic Value, Options exercisable | $ 911 |
Weighted average grant-date fair value of stock options granted (in dollars per share) | $ 1.6 |

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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 -Topic 718 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (c)(1)(iv) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480429/718-10-50-2 + Details
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- Definition 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. + 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)(iv)(03) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480429/718-10-50-2 + 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 -Topic 718 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (c)(1)(iv)(01) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480429/718-10-50-2 + Details
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- Definition The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 718 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (d)(1) -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 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. + 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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