v3.25.3

Fair Value Measurements - Summary of Financial Assets Measured at Fair Value on Recurring Basis by Level within Fair Value Hierarchy (Detail) - Fair Value, Recurring - USD ($) $ in Thousands	Sep. 30, 2025	Dec. 31, 2024
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Amortized Costs	$ 166,407	$ 145,608
Gross Unrealized Holding Gains	166	43
Gross Unrealized Holding Losses	(9)	(1)
Aggregate Fair Value	166,564	145,650
Level 1 \| Short-term investments \| U.S. Treasury securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Amortized Costs	86,748
Gross Unrealized Holding Gains	81
Gross Unrealized Holding Losses	(6)
Aggregate Fair Value	86,823
Level 1 \| Cash equivalents \| Money market funds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Amortized Costs	24,363	110,979
Gross Unrealized Holding Gains	0	0
Gross Unrealized Holding Losses	0	0
Aggregate Fair Value	24,363	110,979
Level 2 \| Short-term investments \| Commercial paper
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Amortized Costs	3,911
Gross Unrealized Holding Gains	5
Gross Unrealized Holding Losses	0
Aggregate Fair Value	3,916
Level 2 \| Short-term investments \| Corporate debt
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Amortized Costs	48,287	34,629
Gross Unrealized Holding Gains	75	43
Gross Unrealized Holding Losses	(3)	(1)
Aggregate Fair Value	48,359	$ 34,671
Level 2 \| Short-term investments \| Foreign entity bond
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Amortized Costs	3,098
Gross Unrealized Holding Gains	5
Gross Unrealized Holding Losses	0
Aggregate Fair Value	$ 3,103

Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) on 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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Outset Medical, Inc. 10-Q