REVENUES - Schedule of Revenue by Segment and Geography (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024
Disaggregation of Revenue [Line Items]
Revenues	$ 701.3	$ 674.9	$ 2,062.9	$ 1,999.4
North America
Disaggregation of Revenue [Line Items]
Revenues	332.7	319.7	986.5	944.4
Europe
Disaggregation of Revenue [Line Items]
Revenues	213.2	191.8	632.2	595.1
Other
Disaggregation of Revenue [Line Items]
Revenues	$ 155.4	$ 163.4	$ 444.2	$ 459.9

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, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

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+ Details

Fortrea Holdings Inc. 10-Q