Long-Term Debt and Revolving Credit Agreements - Schedule of Long-Term Debt (Details) - USD ($) $ in Millions	Sep. 30, 2021	Dec. 31, 2020
Line of Credit Facility [Line Items]
Principal amount	$ 500	$ 370
Deferred issuance costs	(5)	0
Less: current portion	0	(22)
Long-term debt, noncurrent	$ 495	$ 348
Annual contractual interest rate	3.50%	1.77%
Effective interest rate	3.67%	1.87%
2018 Term Loan A | Loans Payable
Line of Credit Facility [Line Items]
Principal amount	$ 0	$ 370
2029 Notes | Loans Payable
Line of Credit Facility [Line Items]
Principal amount	$ 500	$ 0