Debt - Maturities (Details) $ in Millions	Dec. 31, 2020 USD ($)
Debt Instrument [Line Items]
Percentage of contractual interest rate	4.875%
Net carrying amount	$ 2,150
2021	0
2022	700
2023	0
2024	0
2025	0
Thereafter	$ 1,450
Senior Notes \| 4.375% Notes
Debt Instrument [Line Items]
Percentage of contractual interest rate	4.375%
Net carrying amount	$ 800
2021	0
2022	0
2023	0
2024	0
2025	0
Thereafter	$ 800
Senior Notes \| 5.375% Notes
Debt Instrument [Line Items]
Percentage of contractual interest rate	5.375%
Net carrying amount	$ 700
2021	0
2022	700
2023	0
2024	0
2025	0
Thereafter	$ 0
Senior Notes \| 3.875% Notes
Debt Instrument [Line Items]
Percentage of contractual interest rate	3.875%
Net carrying amount	$ 650
2021	0
2022	0
2023	0
2024	0
2025	0
Thereafter	$ 650

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.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
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Amount of long-term debt payable, sinking fund requirement, and other securities issued that are redeemable by holder at fixed or determinable price and date, maturing after fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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