Debt (Summary of debt) (Details) - USD ($)	Apr. 02, 2021	Jan. 01, 2021
Debt Instrument [Line Items]
Total long-term debt	$ 4,766,000,000	$ 4,744,000,000
Less: current portion	(103,000,000)	(100,000,000)
Total long-term debt, net of current portion	4,663,000,000	4,644,000,000
Long-term debt	4,758,000,000	4,782,000,000
Unamortized debt discounts and deferred debt issuances costs	50,000,000	51,000,000
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	$ 58,000,000	13,000,000
Notes payable and finance leases due on various dates through fiscal 2032 \| Minimum
Debt Instrument [Line Items]
Stated interest rate	1.84%
Notes payable and finance leases due on various dates through fiscal 2032 \| Maximum
Debt Instrument [Line Items]
Stated interest rate	5.49%
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	1.49%
Effective interest rate	1.75%
Senior unsecured debt	$ 1,368,000,000	1,391,000,000
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	$ 497,000,000	497,000,000
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	$ 496,000,000	496,000,000
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	$ 737,000,000	737,000,000
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	$ 989,000,000	989,000,000
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	$ 158,000,000	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

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