Fair Value of Financial Instruments - Fair Value Hierarchy (Details) - USD ($) $ in Millions	Sep. 30, 2022		Dec. 31, 2021
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	$ 15,791.8	[1]	$ 16,101.0
Level 1—Price quotations in active markets
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	15.0		30.0
Level 2—Significant other observable inputs
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	600.0		703.0
Level 3—Significant unobservable inputs
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	13,711.0		13,972.0
Investments measured at net asset value
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	$ 1,466.0		$ 1,396.0

[1] Security may be an obligation of one or more entities affiliated with the named company