Consolidated Balance Sheets (Parenthetical) - $ / shares	Apr. 30, 2019	Apr. 30, 2018
Treasury stock, shares	7,360,000	3,531,000
Common stock, shares issued	484,532,000	484,532,000
Common stock, Class A, voting [Member]
Common stock, par value	$ 0.15	$ 0.15
Common stock, shares authorized	170,000,000	170,000,000
Common stock, shares issued	170,000,000	170,000,000
Common Stock, Class B, nonvoting [Member]
Common stock, par value	$ 0.15	$ 0.15
Common stock, shares authorized	400,000,000	400,000,000
Common stock, shares issued	314,532,000	314,532,000

Face amount or stated value per share of common stock.

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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

Total number of common shares of an entity that have been sold or granted to shareholders (includes common shares that were issued, repurchased and remain in the treasury). These shares represent capital invested by the firm's shareholders and owners, and may be all or only a portion of the number of shares authorized. Shares issued include shares outstanding and shares held in the treasury.

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- Definition

Number of common and preferred shares that were previously issued and that were repurchased by the issuing entity and held in treasury on the financial statement date. This stock has no voting rights and receives no dividends.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.29,30)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 30
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6405813&loc=d3e23239-112655

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