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 45

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6451184&loc=d3e28551-108399

Reference 2: http://www.xbrl.org/2003/role/presentationRef

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-Name Accounting Standards Codification

-Topic 835

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-Section 55

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 22

-Article 5

Reference 2: http://www.xbrl.org/2003/role/presentationRef

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-Subparagraph (SX 210.5-02.22(a)(1))

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- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ 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 210.5-02.19(b),22(b))

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef

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- 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

-Glossary Financing Activities

-URI http://asc.fasb.org/extlink&oid=6513228

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

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Short-term Borrowings and Long-term Debt Schedule of 2014 Debt Issuances (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended			0 Months Ended
	Jan. 31, 2015	Jan. 31, 2014	Jan. 31, 2013	Apr. 11, 2013	Oct. 02, 2013
Schedule of 2014 Debt Issuances [Line Items]
Proceeds	$ 5,174	$ 7,072	$ 211
Available	15,000	15,400
Total unsecured debt
Schedule of 2014 Debt Issuances [Line Items]
Proceeds	5,030	6,700
Total unsecured debt \| .600% Debt Issuance, Due 2016 [Domain] [Domain]
Schedule of 2014 Debt Issuances [Line Items]
Principal Amount				1,000
Interest Rate				0.60%
Proceeds				997
Total unsecured debt \| 1.130% Debt Issuance, Due 2018 [Domain]
Schedule of 2014 Debt Issuances [Line Items]
Principal Amount				1,250
Interest Rate				1.13%
Proceeds				1,244
Total unsecured debt \| 2.550% Debt Issuance, Due 2023 [Domain]
Schedule of 2014 Debt Issuances [Line Items]
Principal Amount				1,750
Interest Rate				2.55%
Proceeds				1,738
Total unsecured debt \| 4.000% Debt Issuance, Due 2043 [Domain]
Schedule of 2014 Debt Issuances [Line Items]
Principal Amount				1,000
Interest Rate				4.00%
Proceeds				988
Total unsecured debt \| 1.950% Debt Issuance, Due 2018 [Domain]
Schedule of 2014 Debt Issuances [Line Items]
Principal Amount					1,000
Interest Rate					1.95%
Proceeds					995
Total unsecured debt \| 4.750% Debt Issuance, Due 2043 [Domain]
Schedule of 2014 Debt Issuances [Line Items]
Principal Amount					750
Interest Rate					4.75%
Proceeds					$ 738