v3.25.4

Fair Value Measurements, Cash Equivalents and Marketable Securities - Narrative (Details) - USD ($)	1 Months Ended		12 Months Ended
	Nov. 30, 2023	Jul. 31, 2022	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Initial fair value of contingent consideration at acquisition date			$ 34,000,000	$ 6,050,000
Realized gain (loss) on marketable debt securities			0	0
Recognition of credit losses			0	0
Lunit Inc.
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Number of shares issued for each share of each existing share (in shares)	1
Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Initial fair value of contingent consideration at acquisition date			34,000,000	6,050,000
Contingent consideration liability, noncurrent			$ 34,000,000.0	$ 2,100,000
Lunit Inc.
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Lock up period (in years)		2 years
Unrealized (loss) gain on marketable equity securities					$ 79,700,000

Number Of Shares Issued For Each Share Of Each Existing Share

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Amount of liability recognized arising from contingent consideration in a business combination.

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Amount of increase (decrease) in allowance for credit loss of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amount of realized gain (loss) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), investment in debt security measured at amortized cost (held-to-maturity) and investment in debt security measured at fair value with change in fair value recognized in net income (trading).

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Guardant Health, Inc. 10-K