CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (LOSS) - USD ($)	12 Months Ended
	Apr. 30, 2021	Apr. 30, 2020
CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (LOSS)
Net income (loss)	$ 7,392,000	$ (5,903,000)
Other comprehensive income, net of tax:
Pension settlement, net of tax ($880 in 2020)	0	2,049,000
Decrease (increase) in pension liability, net of tax ($840 in 2021 and $629 in 2020)	1,844,000	(1,485,000)
Other comprehensive income	1,844,000	564,000
Total comprehensive income (loss)	$ 9,236,000	$ (5,339,000)