Reconciliation of Weighted Average Shares Outstanding (Details) - shares shares in Thousands	3 Months Ended
	Jul. 31, 2021	Jul. 31, 2020
Reconciliation of Weighted Average Shares Outstanding [Abstract]
Weighted average shares outstanding (in shares)	55,869	55,916
Less: Unvested restricted shares (in shares)	0	(4)
Shares used for basic earnings per share (in shares)	55,869	55,912
Dilutive effect of unvested restricted stock units and other stock awards (in shares)	730	281
Shares used for diluted earnings per share (in shares)	56,599	56,193
Stock Options [Member]
Reconciliation of Weighted Average Shares Outstanding and Share Repurchases [Abstract]
Antidilutive options to purchase Class A common shares, restricted shares, warrants to purchase Class A common shares, and contingently issuable restricted stock which are excluded from the table above (in shares)	930	1,086