CONSOLIDATED BALANCE SHEETS (Parenthetical) - USD ($) $ in Thousands	Apr. 30, 2021	Apr. 30, 2020
Statement Of Financial Position [Abstract]
Allowance for doubtful accounts	$ 29,324	$ 23,795
Common stock, par value	$ 0.01	$ 0.01
Common stock, shares authorized	150,000,000	150,000,000
Common stock, shares issued	74,915,000	73,205,000
Common stock, shares outstanding	54,008,000	54,450,000