Presentation and Summary of Significant Accounting Policies - Diluted Earnings per Share for Class A Common Shares Using If-Converted Method (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands		12 Months Ended
		Apr. 30, 2024	Apr. 30, 2023	Apr. 30, 2022
Earnings Per Share, Diluted, by Common Class, Including Two Class Method [Line Items]
Basic weighted average common shares (in shares)		33,689	33,761	33,365
Diluted EPS for Common Shares (in shares)		33,725	33,992	34,305
Diluted (in usd per share)	[1]	$ 0.34	$ 0.30	$ 0.38
Class A Common Shares
Earnings Per Share, Diluted, by Common Class, Including Two Class Method [Line Items]
Undistributed and distributed earnings, Per basic		$ 10,758	$ 9,757	$ 12,106
Class B Common Share Conversion		615	555	699
Net earnings		$ 11,373	$ 10,312	$ 12,805
Basic weighted average common shares (in shares)		31,867	31,939	31,543
Common stock equivalents (in shares)		36	231	940
Weighted average number of shares including common stock equivalents, diluted( in shares)		31,903	32,170	32,483
Class B Common Share Conversion (in shares)		1,822	1,822	1,822
Diluted EPS for Common Shares (in shares)		33,725	33,992	34,305
Basic EPS (in usd per share)	[1]	$ 0.34	$ 0.30	$ 0.38
Diluted (in usd per share)		$ 0.34	$ 0.30	$ 0.38

[1] Diluted per share amounts for Class A shares are shown above. Diluted per share for Class B shares under the two-class method are $0.34, $0.30 and $0.38 for the years ended April 30, 2024, 2023 and 2022, respectively. See Note 1(s) to the Consolidated Financial Statements.