Income Taxes (Schedule of Income from U.S. and Foreign Operations) (Details) - USD ($) $ in Millions	12 Months Ended
Apr. 30, 2016	Apr. 30, 2015	Apr. 30, 2014
Domestic and Foreign components of our Income before Income taxes
United States	$ 1,184	$ 912	$ 797
Foreign	305	90	150
Income before income taxes	$ 1,489	$ 1,002	$ 947

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.

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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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