RESTRUCTURING ACTIVITIES - Summary of Related Liabilities (Details) $ in Millions	3 Months Ended
Mar. 31, 2026 USD ($)
Restructuring Reserve [Roll Forward]
Restructuring, beginning balance	$ 53.1
Charges (credits)	55.4
Payments	(28.5)
Other adjustments	(0.9)
Restructuring, ending balance	79.1
2026 Program
Restructuring Reserve [Roll Forward]
Restructuring, beginning balance	0.0
Charges (credits)	56.0
Payments	(8.1)
Other adjustments	(0.5)
Restructuring, ending balance	47.4
Cost Efficiency Program
Restructuring Reserve [Roll Forward]
Restructuring, beginning balance	8.5
Charges (credits)	(0.3)
Payments	(3.0)
Other adjustments	(0.1)
Restructuring, ending balance	5.1
GfK Integration
Restructuring Reserve [Roll Forward]
Restructuring, beginning balance	44.6
Charges (credits)	(0.3)
Payments	(17.4)
Other adjustments	(0.3)
Restructuring, ending balance	$ 26.6

Amount of cash payments made as the result of exit or disposal activities. Excludes payments associated with a discontinued operation or an asset retirement obligation.

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Amount of expenses associated with exit or disposal activities pursuant to an authorized plan. Excludes expenses related to a discontinued operation or an asset retirement obligation.

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Carrying amount (including both current and noncurrent portions of the accrual) as of the balance sheet date pertaining to a specified type of cost associated with exit from or disposal of business activities or restructuring pursuant to a duly authorized plan.

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Amount of increase (decrease) in the restructuring reserve related to foreign currency translation (gain) loss and other increases (decreases).

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