Stock-Based Compensation - Stock Option Activity (Details)	9 Months Ended	12 Months Ended
Sep. 30, 2025 USD ($) $ / shares shares	Dec. 31, 2024 USD ($) $ / shares shares
Options [Roll Forward]
Balance as of December 31, 2024 (in shares) \| shares	598,540
Granted (in shares) \| shares	10,800,137
Cancelled/forfeited/expired (in shares) \| shares	(125,814)
Balance as of September 30, 2025 (in shares) \| shares	11,272,863	598,540
Vested and expected to vest at September 30, 2025 (in shares) \| shares	10,073,271
Exercisable at September 30, 2025 (in shares) \| shares	692,781
Weighted Average Exercise Price [Roll Forward]
Balance as of December 31, 2024 (in dollars per share) \| $ / shares	$ 7.08
Granted (in dollars per share) \| $ / shares	0.61
Cancelled/forfeited (in dollars per share) \| $ / shares	4.5
Balance as of September 30, 2025 (in dollars per share) \| $ / shares	0.91	$ 7.08
Vested and expected to vest at September 30, 2025 (in dollars per share) \| $ / shares	0.94
Exercisable at September 30, 2025 (in dollars per share) \| $ / shares	$ 5.15
Weighted Average Remaining Contractual Life (years) [Roll Forward]
Balance as of September 30, 2025	9 years 9 months 3 days	9 years
Vested and expected to vest at September 30, 2025	9 years 9 months
Exercisable at September 30, 2025	8 years 11 months 26 days
Aggregated Intrinsic Value [Roll Forward]
Balance as of December 31, 2024 \| $	$ 0
Cancelled/forfeited/expired \| $	0
Balance as of September 30, 2025 \| $	1,103	$ 0
Vested and expected to vest as of September 30, 2025 \| $	980
Exercisable at September 30, 2025 \| $	$ 33

Share based compensation arrangement by share based payment award options aggregate intrinsic value.

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- Definition

Share based compensation arrangement by share based payment award options cancelled or forfeited in period total intrinsic value.

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No definition available.

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- Definition

The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

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- Definition

The weighted-average price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on vested portions of options outstanding and currently exercisable under the stock option plan.

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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.

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- Definition

Gross number of share options (or share units) granted during the period.

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- Definition

Amount by which the current fair value of the underlying stock exceeds the exercise price of options outstanding.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480429/718-10-50-2

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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
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-Publisher FASB
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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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No definition available.

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- Definition

Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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- Definition

Weighted-average exercise price, at which grantee can acquire shares reserved for issuance, for 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

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- Definition

Amount by which current fair value of underlying stock exceeds exercise price of fully vested and expected to vest options outstanding. 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)(1)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480429/718-10-50-2

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- Definition

Number of fully vested and expected to vest options outstanding that can 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.

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- Definition

Weighted average price at which grantees could have acquired the underlying shares with respect to stock options that were terminated.

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- Definition

Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options.

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- Definition

Amount of difference between fair value of the underlying shares reserved for issuance and exercise price of vested portions of options outstanding and currently exercisable.

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Weighted average remaining contractual term for vested portions of options outstanding and currently exercisable or convertible, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- Definition

Weighted average remaining contractual term for option awards outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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Weighted average remaining contractual term for fully vested and expected to vest options outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. 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.

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