Minimum threshold limit of percentage of owning stock with voting power on grant date.

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Minimum threshold limit of shares fair value on grant date.

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Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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Aggregate number of common shares reserved for future issuance.

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Amount of cost not yet recognized for nonvested award under share-based payment arrangement.

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Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Amount of cost to be recognized for option under share-based payment arrangement.

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Amount of additional cost recognized for award under share-based payment arrangement from occurrence of event accelerating recognition of cost.

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Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Number of shares authorized for issuance under share-based payment arrangement.

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

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Number of shares for which recognition of cost was accelerated for award under share-based payment arrangement.

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- Definition

Purchase price of common stock expressed as a percentage of its fair value.

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Stock-Based Compensation - Additional Information (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended	9 Months Ended	12 Months Ended
	Sep. 30, 2025	Sep. 30, 2025	Dec. 31, 2024	Dec. 31, 2023
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Common stock reserved for issuance	110,653,031	110,653,031	43,128,526
Weighted Average Exercise Price, Granted			$ 0.92	$ 0.44
Number of options, accelerated vesting	388,988
Accelerated incremental stock based compensation expense	$ 1.1
2025 Employee Stock Purchase Plan
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Common stock reserved for issuance	3,047,669	3,047,669
Purchase price percentage of common stock		85.00%
2025 Incentive Plan
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Common stock reserved for issuance	20,223,481	20,223,481
Number of authorized shares available for issuance	30,500,000	30,500,000
Incentive Stock Options
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Minimum Threshold Limit Of Percentage Of Owning Stock With Voting Power On Grant Date		10.00%
Minimum Threshold Limit Of Shares Fair Value On Grant Date		110.00%
Service-based Options
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Vesting period		4 years
Stock Options [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Uunrecognized compensation cost	$ 15.9	$ 15.9
Unrecognized compensation cost, weighted average period		1 year 9 months 18 days
Weighted Average Exercise Price, Granted	$ 2.05	$ 2.05
RSUs Redeemable Convertible Preferred Stocks [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Unrecognized compensation cost, weighted average period		2 years 8 months 12 days
RSUs unrecognized compensation cost	$ 20.7	$ 20.7
Stock based compensation expense		$ 3.9