Schedule of Debt (Details) $ in Millions		3 Months Ended	6 Months Ended
	Jun. 27, 2018 USD ($)	Jul. 31, 2018 USD ($) Financial_institution	Jul. 31, 2018 USD ($)	Jul. 31, 2017 USD ($)	Jun. 27, 2018 JPY (¥)	Jun. 01, 2018 USD ($)	Apr. 30, 2018 USD ($)	Apr. 11, 2018 USD ($)	Feb. 15, 2018 USD ($)	Jan. 31, 2018 USD ($)
Debt Instrument [Line Items]
Number Of Financial Institutions Committing To Lend Funds Under Lines Of Credit | Financial_institution		22
Long-term debt due within one year		$ 1,090	$ 1,090	$ 3,254						$ 3,738
Long-term debt		44,958	44,958	33,706						30,045
Total		46,048	46,048							33,783
Proceeds from Issuance of Long-term Debt			15,851	$ 1,503
Repayments of long-term debt due within one year			(3,029)
Repayments of long-term debt			(21)
Repayments of long-term debt			3,050
Reclassifications of long-term debt			(364)
Reclassifications of long-term debt			364
Amounts reclassified to short-term debt, total			0
Long-term debt, current maturities, other changes			17
Long-term debt, excluding current maturities, other changes			(553)
Long-term debt, other changes			(536)
Line of Credit Facility, Maximum Borrowing Capacity		15,000	15,000							12,500
5.800% Fixed Rate Debt (500 USD), Due 2018 [Member] | Unsecured debt
Debt Instrument [Line Items]
Debt Instrument, Face Amount									$ 1,250
Debt Instrument, Interest Rate, Stated Percentage									5.80%
Variable Rate Debt, Due 2020 [Domain] | Unsecured debt
Debt Instrument [Line Items]
Debt Instrument, Face Amount | ¥					¥ 0
Proceeds from Issuance of Long-term Debt	$ 748
2.85% Debt Issuance, Due 2020 [Domain] | Unsecured debt
Debt Instrument [Line Items]
Debt Instrument, Face Amount | ¥					¥ 1,250
Debt Instrument, Interest Rate, Stated Percentage					2.85%
Proceeds from Issuance of Long-term Debt	1,247
Variable Date Debt, Due 2021 [Domain] | Unsecured debt
Debt Instrument [Line Items]
Debt Instrument, Face Amount | ¥					¥ 750
Proceeds from Issuance of Long-term Debt	748
3.125% Debt Issuance, Due 2021 [Domain] | Unsecured debt
Debt Instrument [Line Items]
Debt Instrument, Face Amount | ¥					¥ 1,750
Debt Instrument, Interest Rate, Stated Percentage					3.125%
Proceeds from Issuance of Long-term Debt	1,745
3.400% Debt Issuance, Due 2023 [Domain] | Unsecured debt
Debt Instrument [Line Items]
Debt Instrument, Face Amount | ¥					¥ 2,750
Debt Instrument, Interest Rate, Stated Percentage					3.40%
Proceeds from Issuance of Long-term Debt	2,740
3.550% Debt Issuance, Due 2025 [Domain] | Unsecured debt
Debt Instrument [Line Items]
Debt Instrument, Face Amount | ¥					¥ 1,500
Debt Instrument, Interest Rate, Stated Percentage					3.55%
Proceeds from Issuance of Long-term Debt	1,490
3.700% Debt Issuance, Due 2028 [Domain] | Unsecured debt
Debt Instrument [Line Items]
Debt Instrument, Face Amount | ¥					¥ 2,750
Debt Instrument, Interest Rate, Stated Percentage					3.70%
Proceeds from Issuance of Long-term Debt	2,725
3.95% Debt Issuance, Due 2038 [Domain] | Unsecured debt
Debt Instrument [Line Items]
Debt Instrument, Face Amount | ¥					¥ 1,500
Debt Instrument, Interest Rate, Stated Percentage					3.95%
Proceeds from Issuance of Long-term Debt	1,473
4.050% Debt Issuance, Due 2048 [Domain] | Unsecured debt
Debt Instrument [Line Items]
Debt Instrument, Face Amount | ¥					¥ 3,000
Debt Instrument, Interest Rate, Stated Percentage					4.05%
Proceeds from Issuance of Long-term Debt	$ 2,935
1.125% Fixed Rate Debt, Due 2018 [Member] | Unsecured debt
Debt Instrument [Line Items]
Debt Instrument, Face Amount								$ 1,250
Debt Instrument, Interest Rate, Stated Percentage								1.125%
5.498% Fixed Rate Debt, Due 2018 [Member] [Domain] | Unsecured debt
Debt Instrument [Line Items]
Debt Instrument, Face Amount						$ 500
Debt Instrument, Interest Rate, Stated Percentage						5.498%
Five Year Facility [Member]
Debt Instrument [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity							$ 5,000
Three Hundred And Sixty Four Day Facility [Member]
Debt Instrument [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity		$ 10,000	$ 10,000							$ 7,500