Taxes Schedule of Income from Continuing Operations (Details) - USD ($) $ in Millions	12 Months Ended
Jan. 31, 2016	Jan. 31, 2015	Jan. 31, 2014
Taxes [Line Items]
Income (Loss) from Continuing Operations before Income Taxes, Domestic	$ 16,685	$ 18,610	$ 19,412
Income (Loss) from Continuing Operations before Income Taxes, Foreign	4,953	6,189	5,244
Income from continuing operations before income taxes	$ 21,638	$ 24,799	$ 24,656

The portion of earnings or loss from continuing operations before income taxes that is attributable to domestic operations.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(h)(1)(i))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

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- Definition

The portion of earnings or loss from continuing operations before income taxes that is attributable to foreign operations, which is defined as Income or Loss generated from operations located outside the entity's country of domicile.

+ References

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- Definition

Sum of operating profit and nonoperating income or expense before Income or Loss from equity method investments, income taxes, extraordinary items, and noncontrolling interest.

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- Definition

Taxes [Line Items]

+ References

No definition available.

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