Fair Value of Financial Instruments - Additional Information (Details) - Convertible Senior Notes Due 2027 - USD ($) $ in Millions	Sep. 30, 2025	Dec. 31, 2024	Dec. 31, 2021
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Debt instrument, interest rate, stated percentage	0.00%	0.00%	0.00%
Estimated fair value	$ 1,039.3	$ 988.7

The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission.

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+ Details

Confluent, Inc. 10-Q