Subsequent Events (Details) - Senior Notes - USD ($)	Oct. 04, 2021	Sep. 30, 2021	Dec. 31, 2017
2022 Exchangeable Notes
Subsequent Event [Line Items]
Principal amount of long-term debt			$ 517,500,000
Stated interest rate (as a percent)		0.875%
Subsequent Event | 2022 Exchangeable Notes
Subsequent Event [Line Items]
Debt instrument, repurchase amount	$ 414,000,000
Repayment on Exchangeable Notes	$ 1,500,000,000
Subsequent Event | 2022 Exchangeable Notes | Exchangeable Notes Hedge
Subsequent Event [Line Items]
Stock issued during period, conversion of convertible securities (in shares)	5,534,098
Debt instrument, convertible, conversion price (in dollars per share)	$ 158.83
Proceeds from termination of convertible note hedges	$ 201,000,000
Subsequent Event | 3.625% Senior Notes due 2031
Subsequent Event [Line Items]
Principal amount of long-term debt	$ 500,000,000
Stated interest rate (as a percent)	3.625%
Proceeds from issuance of long-term debt used to repurchase debt	$ 420,000,000