Earnings Per Common Share - Basic Earnings Per Common Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands		3 Months Ended		6 Months Ended
		Oct. 31, 2023	Oct. 31, 2022	Oct. 31, 2023	Oct. 31, 2022
Earnings Per Share, Basic, by Common Class, Including Two Class Method [Line Items]
Total from continuing operations (in usd per share)	[1]	$ 0.02	$ 0.06	$ 0.10	$ 0.11
Total from discontinued operations (in usd per share)	[1]	0.05	0	0.05	0.01
Basic (in usd per share)	[1]	$ 0.07	$ 0.06	$ 0.15	$ 0.12
Basic weighted average common shares outstanding (in shares)		34,071	33,720	34,113	33,688
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	$ 0.22	$ 0.22
Undistributed losses (in usd per share)		(0.04)	(0.05)	(0.07)	(0.10)
Total from continuing operations (in usd per share)		0.02	0.06	0.10	0.11
Total from discontinued operations (in usd per share)		0.05	0	0.05	0.01
Basic (in usd per share)		$ 0.07	$ 0.06	$ 0.15	$ 0.12
Distributed earnings		$ 3,556	$ 3,511	$ 7,114	$ 7,017
Undistributed losses		(1,319)	(1,519)	(2,276)	(3,072)
Total from continuing operations		495	1,803	2,962	3,667
Total from discontinued operations		1,742	189	1,876	278
Total		$ 2,237	$ 1,992	$ 4,838	$ 3,945
Basic weighted average common shares outstanding (in shares)		32,249	31,898	32,291	31,866
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	$ 0.22	$ 0.22
Undistributed losses (in usd per share)		(0.04)	(0.05)	(0.07)	(0.10)
Total from continuing operations (in usd per share)		0.07	0.06	0.15	0.12
Total from discontinued operations (in usd per share)		0	0	0	0
Basic (in usd per share)		$ 0.07	$ 0.06	$ 0.15	$ 0.12
Distributed earnings		$ 201	$ 200	$ 401	$ 400
Undistributed losses		(75)	(87)	(128)	(176)
Total from continuing operations		126	113	273	224
Total from discontinued operations		0	0	0	0
Total		$ 126	$ 113	$ 273	$ 224
Basic weighted average common shares outstanding (in shares)		1,822	1,822	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 $0.07 and $0.06 for the three months ended October 31, 2023 and 2022, and $0.15 and $0.12 for the six months ended October 31, 2023 and 2022. See Note D to the condensed consolidated financial statements.