Aggregate adjustment to retained earnings to account for a stock split made without a change in per-share par value.

No definition available.

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- Definition

Face amount or stated value per share of common stock.

+ 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 210.5-02.29)

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

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 30

-Article 5

+ Details

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- Definition

The maximum number of common shares permitted to be issued by an entity's charter and bylaws.

+ References

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- Definition

Ratio applied to the conversion of stock split, for example but not limited to, one share converted to two or two shares converted to one.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Stock Split

-URI http://asc.fasb.org/extlink&oid=6525746

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section S99

-Paragraph 4

-Subparagraph (SAB TOPIC 4.C)

-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187143-122770

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Stock Split (Details) (USD $) In Millions, except Share data, unless otherwise specified	0 Months Ended	12 Months Ended							0 Months Ended		0 Months Ended	12 Months Ended
	Jun. 14, 2012	Apr. 30, 2014 Common stock, Class A, voting [Member]	Apr. 30, 2013 Common stock, Class A, voting [Member]	Apr. 30, 2012 Common stock, Class A, voting [Member]	Jul. 26, 2012 Common stock, Class A, voting [Member] After Amendment [Member]	Jul. 26, 2012 Common stock, Class A, voting [Member] Before Amendment [Member]	Jul. 26, 2012 Common Class B [Member] After Amendment [Member]	Jul. 26, 2012 Common Class B [Member] Before Amendment [Member]	Aug. 03, 2013 Common Stock [Member]	Aug. 03, 2012 Common Stock [Member]	Aug. 03, 2013 Treasury Stock [Member]	Apr. 30, 2014 Treasury Stock [Member]	Apr. 30, 2013 Treasury Stock [Member]	Apr. 30, 2012 Treasury Stock [Member]
Class of Stock [Line Items]
Stock split conversion ratio	1.5
Common stock, shares authorized (shares)		85,000,000	85,000,000		85,000,000	57,000,000	400,000,000	100,000,000
Adjustment to retained earnings due to stock split		$ 0	$ (4)	$ 0					$ 10		$ (8)	$ 0	$ (8)	$ 0
Common stock, par value (dollars per share)		$ 0.15	$ 0.15							$ 0.15