Debt - Long Term Debt Outstanding (Details)	Jun. 30, 2020 USD ($)	Jun. 30, 2020 EUR (€)	Dec. 31, 2019 USD ($)
Debt Instrument [Line Items]
Total debt	$ 7,653,000,000		$ 4,938,000,000
Current maturities of long-term debt	(750,000,000)		(749,000,000)
Long-term debt, excluding current maturities	6,903,000,000		4,189,000,000
Revolving Credit Facility
Debt Instrument [Line Items]
Credit facility borrowings outstanding	1,900,000,000		0
5.95% senior notes due 2020
Debt Instrument [Line Items]
Total debt	$ 750,000,000		749,000,000
Debt, interest rate (percentage)	5.95%	5.95%
Senior unsecured notes principal amount	$ 750,000,000
2.5% (€650 million) senior notes due 2022
Debt Instrument [Line Items]
Total debt	$ 729,000,000		725,000,000
Debt, interest rate (percentage)	2.50%	2.50%
Senior unsecured notes principal amount \| €		€ 650,000,000
4.5% senior notes due 2024
Debt Instrument [Line Items]
Total debt	$ 497,000,000		497,000,000
Debt, interest rate (percentage)	4.50%	4.50%
Senior unsecured notes principal amount	$ 500,000,000
6.25% senior notes due 2025
Debt Instrument [Line Items]
Total debt	$ 1,970,000,000		0
Debt, interest rate (percentage)	6.25%	6.25%
7.0% senior notes due 2025
Debt Instrument [Line Items]
Total debt	$ 739,000,000		0
Debt, interest rate (percentage)	7.00%	7.00%
5.0% senior notes due 2026
Debt Instrument [Line Items]
Total debt	$ 744,000,000		743,000,000
Debt, interest rate (percentage)	5.00%	5.00%
Senior unsecured notes principal amount	$ 750,000,000
3.8% senior notes due 2028
Debt Instrument [Line Items]
Total debt	$ 992,000,000		992,000,000
Debt, interest rate (percentage)	3.80%	3.80%
Senior unsecured notes principal amount	$ 1,000,000,000
3.25% senior notes due 2030
Debt Instrument [Line Items]
Total debt	$ 1,232,000,000		$ 1,232,000,000
Debt, interest rate (percentage)	3.25%	3.25%
Senior unsecured notes principal amount	$ 1,250,000,000

Face (par) amount of debt instrument at time of issuance.

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt, classified as current. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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