Long-Term Debt - Schedule of Long Term Debt (Details) - USD ($) $ in Millions	9 Months Ended
Sep. 30, 2021	Dec. 31, 2020
Long-term debt
Long-term debt, gross	$ 10,449
Unamortized premiums, net	36	$ 60
Unamortized debt issuance costs	(59)	(54)
Long-term Debt and Lease Obligation, Including Current Maturities, Total	10,426	10,387
Less current maturities	(24)	(14)
Long-term debt, excluding current maturities	10,402	10,373
Senior notes \| Senior Notes Maturing 2027-2029
Long-term debt
Long-term debt, gross	$ 1,500	1,500
Senior notes \| Senior Notes Maturing 2027-2029 \| Minimum
Long-term debt
Stated interest rate	3.40%
Senior notes \| Senior Notes Maturing 2027-2029 \| Maximum
Long-term debt
Stated interest rate	3.875%
Senior notes \| Senior Notes Maturing 2025-2029
Long-term debt
Long-term debt, gross	$ 5,515	5,515
Senior notes \| Senior Notes Maturing 2025-2029 \| Minimum
Long-term debt
Stated interest rate	3.625%
Senior notes \| Senior Notes Maturing 2025-2029 \| Maximum
Long-term debt
Stated interest rate	5.375%
Term loan \| Tranche B 2027 Term Loan
Long-term debt
Long-term debt, gross	$ 3,111	$ 3,111
Effective percentage	1.835%	1.897%
Term loan \| Tranche B 2027 Term Loan \| LIBOR
Long-term debt
Basis spread on variable rate	1.75%
Finance leases and other obligations
Long-term debt
Long-term debt, gross	$ 323	$ 255

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

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Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

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Contractual interest rate for funds borrowed, under the debt agreement.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Amount, after accumulated amortization, of debt discount (premium).

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Amount, after accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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Amount of long-term debt and lease obligation, classified as noncurrent.

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Amount of long-term debt and lease obligation, including portion classified as current.

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