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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 55
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=64930739&loc=d3e28878-108400

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=64930785&loc=d3e28551-108399

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22(a)(1))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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Balance Type:	na
Period Type:	instant

- Definition

The cash inflow from a debt initially having maturity due after one year or beyond the operating cycle, if longer.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 14
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3255-108585

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Financing Activities
-URI http://asc.fasb.org/extlink&oid=6513228

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Balance Type:	debit
Period Type:	duration

- Definition

[Line Items] for Schedule of Fiscal Year 2018 Debt Issuances [Table]

+ References

No definition available.

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Long-term Debt Schedule of 2018 Debt Issuances (Details) ¥ in Millions, $ in Millions		6 Months Ended
	Jul. 18, 2017 USD ($)	Jul. 31, 2017 USD ($)	Jul. 31, 2016 USD ($)	Jul. 18, 2017 JPY (¥)
Schedule of Fiscal Year 2018 Debt Issuances [Line Items]
Proceeds from issuance of long-term debt		$ 1,503	$ 130
Unsecured debt \| 0.183% Debt Issuance, Due 2022 [Domain]
Schedule of Fiscal Year 2018 Debt Issuances [Line Items]
Principal Amount \| ¥				¥ 70,000
Interest Rate				0.183%
Proceeds from issuance of long-term debt	$ 619
Unsecured debt \| 0.298% Debt Issuance, Due 2024 [Domain]
Schedule of Fiscal Year 2018 Debt Issuances [Line Items]
Principal Amount \| ¥				¥ 40,000
Interest Rate				0.298%
Proceeds from issuance of long-term debt	354
Unsecured debt \| 0.520% Debt Issuance, Due 2027 [Domain]
Schedule of Fiscal Year 2018 Debt Issuances [Line Items]
Principal Amount \| ¥				¥ 60,000
Interest Rate				0.52%
Proceeds from issuance of long-term debt	$ 530