Earnings Per Common Share - Basic Earnings Per Common Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands		3 Months Ended
		Jul. 31, 2022	Jul. 31, 2021
Earnings Per Share, Basic, by Common Class, Including Two Class Method [Line Items]
Total (in usd per share)	[1]	$ 0.06	$ 0.09
Basic weighted average common shares outstanding (in shares)		33,656	33,053
Class A Common Shares
Earnings Per Share, Basic, by Common Class, Including Two Class Method [Line Items]
Distributed earnings (in usd per share)		$ 0.11	$ 0.11
Undistributed losses (in usd per share)		(0.05)	(0.02)
Total (in usd per share)		$ 0.06	$ 0.09
Distributed earnings		$ 3,505	$ 3,457
Undistributed losses		(1,488)	(673)
Total		$ 2,017	$ 2,784
Basic weighted average common shares outstanding (in shares)		31,834	31,231
Class B Common Shares
Earnings Per Share, Basic, by Common Class, Including Two Class Method [Line Items]
Distributed earnings (in usd per share)		$ 0.11	$ 0.11
Undistributed losses (in usd per share)		(0.05)	(0.02)
Total (in usd per share)		$ 0.06	$ 0.09
Distributed earnings		$ 201	$ 202
Undistributed losses		(85)	(39)
Total		$ 116	$ 163
Basic weighted average common shares outstanding (in shares)		1,822	1,822

[1] Basic per share amounts are the same for Class A and Class B shares. Diluted per share amounts for Class A shares are shown above. Diluted earnings per share for Class B shares under the two-class method are $0.06 and $0.09 for the three months ended July 31, 2022 and 2021. See Note D to the Condensed Consolidated Financial Statements.