Borrowing Facilities and Debt - Debt Outstanding (Details) - USD ($) $ in Millions	Jan. 26, 2020	Oct. 27, 2019
Debt Instrument [Line Items]
Current portion of long-term debt	$ 600	$ 600
Long-term debt, principal amount	4,800	4,800
Total long-term debt	4,714	4,713
Total debt	5,314	5,313
Senior Notes
Debt Instrument [Line Items]
Long-term debt, principal amount	4,750	4,750
Total unamortized discount	(10)	(10)
Total unamortized debt issuance costs	(26)	(27)
Senior Notes \| 2.625% Senior Notes Due 2020
Debt Instrument [Line Items]
Current portion of long-term debt	$ 600	600
Stated interest rate (as percent)	2.625%
Effective Interest Rate	2.64%
Senior Notes \| 4.300% Senior Notes Due 2021
Debt Instrument [Line Items]
Stated interest rate (as percent)	4.30%
Long-term debt, principal amount	$ 750	750
Effective Interest Rate	4.326%
Senior Notes \| 3.900% Senior Notes Due 2025
Debt Instrument [Line Items]
Stated interest rate (as percent)	3.90%
Long-term debt, principal amount	$ 700	700
Effective Interest Rate	3.944%
Senior Notes \| 3.300% Senior Notes Due 2027
Debt Instrument [Line Items]
Stated interest rate (as percent)	3.30%
Long-term debt, principal amount	$ 1,200	1,200
Effective Interest Rate	3.342%
Senior Notes \| 5.100% Senior Notes Due 2035
Debt Instrument [Line Items]
Stated interest rate (as percent)	5.10%
Long-term debt, principal amount	$ 500	500
Effective Interest Rate	5.127%
Senior Notes \| 5.850% Senior Notes Due 2041
Debt Instrument [Line Items]
Stated interest rate (as percent)	5.85%
Long-term debt, principal amount	$ 600	600
Effective Interest Rate	5.879%
Senior Notes \| 4.350% Senior Notes Due 2047
Debt Instrument [Line Items]
Stated interest rate (as percent)	4.35%
Long-term debt, principal amount	$ 1,000	$ 1,000
Effective Interest Rate	4.361%

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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Amount, after accumulated amortization, of debt discount.

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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, 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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