Fair Value Measurements Fair Value of Assets and Liabilities Measured on a Recurring Basis (Tables)

12 Months Ended

Dec. 31, 2023

Fair Value Disclosures [Abstract]

Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis [Table Text Block]

The following tables present information about our financial instruments measured at fair value on a recurring basis as of December 31, 2023 and 2022, and indicates the fair value hierarchy of the valuation techniques utilized to determine such fair value.

	December 31, 2023								Balance Sheet Classification
	Level 1		Level 2		Level 3		Total
Assets
Cash equivalents	$	1,521.5	$	—	$	—	$	1,521.5	Cash and cash equivalents
Liabilities
Contingent acquisition obligations 1	$	—	$	—	$	3.1	$	3.1	Accrued liabilities and Other non-current liabilities
	December 31, 2022								Balance Sheet Classification
	Level 1		Level 2		Level 3		Total
Assets
Cash equivalents	$	1,688.1	—		—		$	1,688.1	Cash and cash equivalents
Liabilities
Contingent acquisition obligations 1	—		—		21.6		$	21.6	Accrued liabilities and Other non-current liabilities

1Contingent acquisition obligations includes deferred acquisition payments and unconditional obligations to purchase additional non-controlling equity shares of consolidated subsidiaries. Fair value measurement of the obligations is based upon actual and projected operating performance targets as specified in the related agreements. The decrease in this balance of $18.5 from December 31, 2022 to December 31, 2023 is primarily due to payments related to our deferred acquisitions from prior-year acquisitions and valuation adjustments, partially offset by the addition of a new contingent acquisition obligation and the exercises of redeemable non-controlling interest. The amounts payable within the next twelve months are classified in accrued liabilities; any amounts payable thereafter are classified in other non-current liabilities.