Background and Basis of Presentation - Narrative (Details) $ in Millions	3 Months Ended	9 Months Ended
	Sep. 30, 2024 USD ($)	Sep. 30, 2025 segment	Sep. 30, 2024 USD ($)	Dec. 31, 2024 USD ($)
Debt Instrument [Line Items]
Number of operating segments \| segment		1
Number of reportable segments \| segment		1
Goodwill, impairment loss \| $	$ 195.7		$ 635.4
Revision of Prior Period, Reclassification, Adjustment
Debt Instrument [Line Items]
Deferred tax assets \| $				$ 1.0

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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+ Details

- Definition

Amount of impairment loss from asset representing future economic benefit arising from other asset acquired in business combination or from joint venture formation or both, that is not individually identified and separately recognized.

+ References + Details

CHEGG, INC 10-Q