Other Balance Sheet Accounts - Summary of Accrued Expenses and Other Current Liabilities (Detail) - USD ($) $ in Thousands	Sep. 30, 2025	Dec. 31, 2024
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Accrued salaries and other payroll liabilities	$ 39,150	$ 10,368
Accrued professional services and transaction costs	26,464	936
Acquisition holdback liabilities	5,600	3,300
Accrued equipment and facilities liabilities	12,137	534
Accrued expenses—other	8,505	1,673
Total accrued expenses and other current liabilities	$ 91,856	$ 16,811

Accrued equipment and facilities current liabilities.

No definition available.

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- Definition

Acquisition holdback liabilities.

+ References

No definition available.

+ Details

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- Definition

Carrying value as of the balance sheet date of obligations incurred and payable, pertaining to costs that are statutory in nature, are incurred on contractual obligations, or accumulate over time and for which invoices have not yet been received or will not be rendered. Examples include taxes, interest, rent and utilities. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 210
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(20))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1

+ Details

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- Definition

Carrying value as of the balance sheet date of obligations incurred through that date and payable for professional fees, such as for legal and accounting services received. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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+ Details

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- Definition

Total of the carrying values as of the balance sheet date of obligations incurred through that date and payable for obligations related to services received from employees, such as accrued salaries and bonuses, payroll taxes and fringe benefits. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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+ Details

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Data Type:	xbrli:monetaryItemType
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Period Type:	instant

- References

No definition available.

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- Definition

Amount of expenses incurred but not yet paid classified as other, due within one year or the normal operating cycle, if longer.

+ References

+ Details

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