Fair Value Measurements (Details) $ in Millions	1 Months Ended	3 Months Ended
	Aug. 31, 2025 USD ($)	Dec. 31, 2025 USD ($) contract	Mar. 31, 2026 USD ($)
Fair value of assets and liabilities measured on recurring basis
Cumulative loss before tax		$ 88.0
Cumulative after-tax loss		$ 67.4
Net Investment Hedging [Member]
Fair value of assets and liabilities measured on recurring basis
Number of foreign exchange forward contracts | contract		0
Cash Flow Hedging [Member]
Fair value of assets and liabilities measured on recurring basis
Number of foreign exchange forward contracts | contract		0
Treasury Lock With 10 Year Term | Cash Flow Hedging [Member]
Fair value of assets and liabilities measured on recurring basis
Aggregate value of net derivative instrument	$ 1,500.0
Derivative instruments period (in years)	10 years
Treasury Lock With 30 Year Term | Cash Flow Hedging [Member]
Fair value of assets and liabilities measured on recurring basis
Aggregate value of net derivative instrument	$ 1,000.0
Derivative instruments period (in years)	30 years
4.625% Senior Notes Due February 2036
Fair value of assets and liabilities measured on recurring basis
Stated interest rate (as a percent)		4.625%
5.300% Senior Notes Due November 2055
Fair value of assets and liabilities measured on recurring basis
Stated interest rate (as a percent)		5.30%
Fair Value, Recurring [Member]
Fair value of assets and liabilities measured on recurring basis
Short-term investments		$ 303.6	$ 455.1
Long-term investments		0.2	0.4
Forward contracts		0.3	(12.5)
Redeemable noncontrolling interests		(9.3)	(9.1)
Total asset		294.8	433.9
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 1 [Member]
Fair value of assets and liabilities measured on recurring basis
Short-term investments		0.0	0.0
Long-term investments		0.0	0.0
Forward contracts		0.0	0.0
Redeemable noncontrolling interests		0.0	0.0
Total asset		0.0	0.0
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 2 [Member]
Fair value of assets and liabilities measured on recurring basis
Short-term investments		303.6	455.1
Long-term investments		0.2	0.4
Forward contracts		0.3	(12.5)
Redeemable noncontrolling interests		0.0	0.0
Total asset		304.1	443.0
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 3 [Member]
Fair value of assets and liabilities measured on recurring basis
Short-term investments		0.0	0.0
Long-term investments		0.0	0.0
Forward contracts		0.0	0.0
Redeemable noncontrolling interests		(9.3)	(9.1)
Total liability		$ (9.3)	$ (9.1)