Consolidated Statements of Shareholders' Equity Consolidated Statements of Shareholders' Equity - USD ($) $ in Thousands	Total	Common stock	Retained earnings
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Implementation of ASU 2014-09	$ (4,140)		$ (4,140)
Beginning Balance (shares) at Apr. 30, 2018		36,874,322,000
Beginning Balance at Apr. 30, 2018	1,271,141	$ 0	1,271,141
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	136,839		136,839
Dividends declared	(21,216)		(21,216)
Exercise of stock options (in shares)		11,292,000
Exercise of stock options	$ 379	$ 379
Repurchase of common stock (shares)	(352,592,000)
Repurchase of common stock	$ (35,247)		(35,247)
Stock based compensation (shares)		70,984,000
Stock based compensation	9,323	$ 9,323
Ending Balance (shares) at Oct. 31, 2018		36,604,006,000
Ending Balance at Oct. 31, 2018	$ 1,357,079	$ 9,702	$ 1,347,377

Number of shares of common stock outstanding. Common stock represent the ownership interest in a corporation.

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Amount after tax of increase (decrease) to equity or (increase) decrease to net assets, resulting from the cumulative effect adjustment of a new accounting principle applied in the period of adoption.

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Amount of paid and unpaid common stock dividends declared with the form of settlement in cash, stock and payment-in-kind (PIK).

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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