Fair Value of Financial Instruments - Fair Value Hierarchy (Details) - USD ($) $ in Millions	Sep. 30, 2023		Dec. 31, 2022
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	$ 14,666.1	[1]	$ 15,377.3	[2]
Level 1—Price quotations in active markets
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	1.0		0.0
Level 2—Significant other observable inputs
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	231.0		564.0
Level 3—Significant unobservable inputs
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	13,031.0		13,385.0
Investments measured at net asset value
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	$ 1,403.0		$ 1,428.0

[1] See Note 8 for additional information regarding the fair value of the Company’s financial instruments

[2] Fair value determined by the Company’s board of directors (see Note 8).