Debt (Summary of Debt) (Details) - USD ($)	Sep. 30, 2022	Dec. 31, 2021
Debt Instrument [Line Items]
Total short-term debt	$ 380,000,000	$ 380,000,000
Total long-term debt	4,622,000,000	4,696,000,000
Less current portion	(647,000,000)	(103,000,000)
Total long-term debt, net of current portion	3,975,000,000	4,593,000,000
Long-term debt	4,994,000,000	5,065,000,000
Unamortized debt discounts and deferred debt issuances costs	37,000,000	43,000,000
Unsecured Debt \| $1,925 million term loan, due January 2025
Debt Instrument [Line Items]
Debt instrument, face amount	$ 1,925,000,000
Stated interest rate	4.50%
Effective interest rate	4.81%
Senior unsecured debt	$ 1,228,000,000	1,298,000,000
Unsecured Debt \| $500 million notes, due May 2023
Debt Instrument [Line Items]
Debt instrument, face amount	$ 500,000,000
Stated interest rate	2.95%
Effective interest rate	3.17%
Senior unsecured debt	$ 499,000,000	498,000,000
Unsecured Debt \| $500 million notes, due May 2025
Debt Instrument [Line Items]
Debt instrument, face amount	$ 500,000,000
Stated interest rate	3.63%
Effective interest rate	3.76%
Senior unsecured debt	$ 498,000,000	497,000,000
Unsecured Debt \| $750 million notes due May 2030
Debt Instrument [Line Items]
Debt instrument, face amount	$ 750,000,000
Stated interest rate	4.38%
Effective interest rate	4.50%
Senior unsecured debt	$ 739,000,000	738,000,000
Unsecured Debt \| $1,000 million notes, due February 2031
Debt Instrument [Line Items]
Debt instrument, face amount	$ 1,000,000,000
Stated interest rate	2.30%
Effective interest rate	2.38%
Senior unsecured debt	$ 991,000,000	990,000,000
Unsecured Debt \| $250 million notes, due July 2032
Debt Instrument [Line Items]
Debt instrument, face amount	$ 250,000,000
Stated interest rate	7.13%
Effective interest rate	7.43%
Senior unsecured debt	$ 247,000,000	247,000,000
Unsecured Debt \| $300 million notes, due July 2033
Debt Instrument [Line Items]
Debt instrument, face amount	$ 300,000,000
Stated interest rate	5.50%
Effective interest rate	5.88%
Senior unsecured debt	$ 159,000,000	158,000,000
Unsecured Debt \| $300 million notes, due December 2040
Debt Instrument [Line Items]
Debt instrument, face amount	$ 300,000,000
Stated interest rate	5.95%
Effective interest rate	6.03%
Senior unsecured debt	$ 216,000,000	216,000,000
Unsecured Debt \| Notes payable and finance leases due on various dates through fiscal 2032
Debt Instrument [Line Items]
Notes payable and finance leases due on various dates through fiscal 2032	$ 45,000,000	54,000,000
Unsecured Debt \| Notes payable and finance leases due on various dates through fiscal 2032 \| Minimum
Debt Instrument [Line Items]
Stated interest rate	1.84%
Unsecured Debt \| Notes payable and finance leases due on various dates through fiscal 2032 \| Maximum
Debt Instrument [Line Items]
Stated interest rate	4.30%
Unsecured Debt \| $380 million term loan, due May 2022
Debt Instrument [Line Items]
Debt instrument, face amount	$ 380,000,000
Stated interest rate	1.54%
Effective interest rate	1.64%
Senior unsecured debt	$ 0	380,000,000
Unsecured Debt \| $380 million term loan, due May 2023
Debt Instrument [Line Items]
Debt instrument, face amount	$ 380,000,000
Stated interest rate	4.13%
Effective interest rate	4.22%
Senior unsecured debt	$ 380,000,000	$ 0

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