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Redeemable Convertible Preferred Stock (Details) - USD ($) $ in Thousands | Sep. 30, 2025 | Jun. 30, 2025 | Dec. 31, 2024 | Sep. 30, 2024 | Jun. 30, 2024 | Dec. 31, 2023
--- | --- | --- | --- | --- | --- | ---
Temporary Equity [Line Items] |  |  |  |  |  |
Shares Authorized (in shares) | 29,544,989 |  | 29,544,989 |  |  |
Shares Issued (in shares) | 29,084,235 |  | 29,084,235 |  |  |
Shares Outstanding (in shares) | 29,084,235 | 29,084,235 | 29,084,235 | 29,084,235 | 29,084,235 | 22,701,179
Net Carrying Value | $ 419,409 |  | $ 419,409 |  |  |
Aggregate Liquidation Preference | $ 422,458 |  | $ 422,458 |  |  |
Series A-1 |  |  |  |  |  |
Temporary Equity [Line Items] |  |  |  |  |  |
Shares Authorized (in shares) | 1,349,650 |  | 1,349,650 |  |  |
Shares Issued (in shares) | 1,349,650 |  | 1,349,650 |  |  |
Shares Outstanding (in shares) | 1,349,650 |  | 1,349,650 |  |  |
Net Carrying Value | $ 3,493 |  | $ 3,493 |  |  |
Aggregate Liquidation Preference | $ 540 |  | $ 540 |  |  |
Series A-2 |  |  |  |  |  |
Temporary Equity [Line Items] |  |  |  |  |  |
Shares Authorized (in shares) | 1,137,210 |  | 1,137,210 |  |  |
Shares Issued (in shares) | 1,137,210 |  | 1,137,210 |  |  |
Shares Outstanding (in shares) | 1,137,210 |  | 1,137,210 |  |  |
Net Carrying Value | $ 2,943 |  | $ 2,943 |  |  |
Aggregate Liquidation Preference | $ 910 |  | $ 910 |  |  |
Series A-3 |  |  |  |  |  |
Temporary Equity [Line Items] |  |  |  |  |  |
Shares Authorized (in shares) | 899,730 |  | 899,730 |  |  |
Shares Issued (in shares) | 899,730 |  | 899,730 |  |  |
Shares Outstanding (in shares) | 899,730 |  | 899,730 |  |  |
Net Carrying Value | $ 2,328 |  | $ 2,328 |  |  |
Aggregate Liquidation Preference | $ 900 |  | $ 900 |  |  |
Series A-4 |  |  |  |  |  |
Temporary Equity [Line Items] |  |  |  |  |  |
Shares Authorized (in shares) | 25,761 |  | 25,761 |  |  |
Shares Issued (in shares) | 25,761 |  | 25,761 |  |  |
Shares Outstanding (in shares) | 25,761 |  | 25,761 |  |  |
Net Carrying Value | $ 67 |  | $ 67 |  |  |
Aggregate Liquidation Preference | $ 50 |  | $ 50 |  |  |
Series A-5 |  |  |  |  |  |
Temporary Equity [Line Items] |  |  |  |  |  |
Shares Authorized (in shares) | 114,613 |  | 114,613 |  |  |
Shares Issued (in shares) | 114,613 |  | 114,613 |  |  |
Shares Outstanding (in shares) | 114,613 |  | 114,613 |  |  |
Net Carrying Value | $ 297 |  | $ 297 |  |  |
Aggregate Liquidation Preference | $ 100 |  | $ 100 |  |  |
Series A-6 |  |  |  |  |  |
Temporary Equity [Line Items] |  |  |  |  |  |
Shares Authorized (in shares) | 5,805,861 |  | 5,805,861 |  |  |
Shares Issued (in shares) | 5,796,201 |  | 5,796,201 |  |  |
Shares Outstanding (in shares) | 5,796,201 |  | 5,796,201 |  |  |
Net Carrying Value | $ 14,999 |  | $ 14,999 |  |  |
Aggregate Liquidation Preference | $ 15,000 |  | $ 15,000 |  |  |
Series B-1 |  |  |  |  |  |
Temporary Equity [Line Items] |  |  |  |  |  |
Shares Authorized (in shares) | 5,182,287 |  | 5,182,287 |  |  |
Shares Issued (in shares) | 5,182,287 |  | 5,182,287 |  |  |
Shares Outstanding (in shares) | 5,182,287 |  | 5,182,287 |  |  |
Net Carrying Value | $ 54,889 |  | $ 54,889 |  |  |
Aggregate Liquidation Preference | $ 55,000 |  | $ 55,000 |  |  |
Series B-2 |  |  |  |  |  |
Temporary Equity [Line Items] |  |  |  |  |  |
Shares Authorized (in shares) | 2,566,902 |  | 2,566,902 |  |  |
Shares Issued (in shares) | 2,566,902 |  | 2,566,902 |  |  |
Shares Outstanding (in shares) | 2,566,902 |  | 2,566,902 |  |  |
Net Carrying Value | $ 27,243 |  | $ 27,243 |  |  |
Aggregate Liquidation Preference | $ 16,025 |  | $ 16,025 |  |  |
Series C |  |  |  |  |  |
Temporary Equity [Line Items] |  |  |  |  |  |
Shares Authorized (in shares) | 6,079,919 |  | 6,079,919 |  |  |
Shares Issued (in shares) | 5,628,825 |  | 5,628,825 |  |  |
Shares Outstanding (in shares) | 5,628,825 |  | 5,628,825 |  |  |
Net Carrying Value | $ 143,268 |  | $ 143,268 |  |  |
Aggregate Liquidation Preference | $ 143,500 |  | $ 143,500 |  |  |
Series C-1 |  |  |  |  |  |
Temporary Equity [Line Items] |  |  |  |  |  |
Shares Authorized (in shares) | 1,726,823 |  | 1,726,823 |  |  |
Shares Issued (in shares) | 1,726,823 |  | 1,726,823 |  |  |
Shares Outstanding (in shares) | 1,726,823 |  | 1,726,823 |  |  |
Net Carrying Value | $ 39,886 |  | $ 39,886 |  |  |
Aggregate Liquidation Preference | $ 33,870 |  | $ 33,870 |  |  |
Series D |  |  |  |  |  |
Temporary Equity [Line Items] |  |  |  |  |  |
Shares Authorized (in shares) | 4,656,233 |  | 4,656,233 |  |  |
Shares Issued (in shares) | 4,656,233 |  | 4,656,233 |  |  |
Shares Outstanding (in shares) | 4,656,233 |  | 4,656,233 |  |  |
Net Carrying Value | $ 129,996 |  | $ 129,996 |  |  |
Aggregate Liquidation Preference | $ 156,563 |  | $ 156,563 |  |  |

X
- Definition Aggregate amount of redemption requirements for each class or type of redeemable stock classified as temporary equity for each of the five years following the latest balance sheet date. The redemption requirement does not constitute an unconditional obligation that will be settled in a variable number of shares constituting a monetary value predominantly indexed to (a) a fixed monetary amount known at inception, (b) an amount inversely correlated with the residual value of the entity, or (c) an amount determined by reference to something other than the fair value of issuer's stock. Does not include mandatorily redeemable stock. The exception is if redemption is required upon liquidation or termination of the reporting entity. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 815 -SubTopic 40 -Name Accounting Standards Codification -Section 50 -Paragraph 5 -Subparagraph (e) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480237/815-40-50-5 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 480 -SubTopic 10 -Name Accounting Standards Codification -Section S50 -Paragraph 1 -Publisher FASB -URI https://asc.fasb.org/1943274/2147479857/480-10-S50-1 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Topic 480 -SubTopic 10 -Name Accounting Standards Codification -Section S50 -Paragraph 3 -Publisher FASB -URI https://asc.fasb.org/1943274/2147479857/480-10-S50-3 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Topic 480 -SubTopic 10 -Name Accounting Standards Codification -Section S45 -Paragraph 3 -Publisher FASB -URI https://asc.fasb.org/1943274/2147479887/480-10-S45-3 Reference 5: http://www.xbrl.org/2003/role/disclosureRef -Topic 480 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 3A -Subparagraph (24)(b) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480244/480-10-S99-3A + Details
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