Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Apr. 30, 2021	Apr. 30, 2020
Statement of Financial Position [Abstract]
Allowance for doubtful accounts	$ 70,689	$ 64,648
Accumulated depreciation and amortization	$ 832,885	$ 796,192
Common stock, no par value (USD per share)	$ 0	$ 0
Common stock, stated value per share (in usd per share)	$ 0.01	$ 0.01
Common stock, shares authorized (in shares)	800,000,000	800,000,000
Common stock, shares issued (in shares)	216,655,616	228,206,684
Treasury stock, shares (in shares)	35,189,707	35,731,376

Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

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Amount of allowance for credit loss on accounts receivable, classified as current.

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