Condensed Consolidated Statements of Comprehensive Income (Unaudited) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Oct. 31, 2021	Oct. 31, 2020	Oct. 31, 2021	Oct. 31, 2020
Statement of Comprehensive Income [Abstract]
Net income	$ 2,030	$ 23,122	$ 5,011	$ 39,181
Other comprehensive income, net of tax:
Change in pension benefits, net of deferred taxes of $125 and $111, and $251 and $224 for the three and six months ended October 31, 2021 and 2020, respectively	373	329	746	656
Change in cash flow hedges (swap), net of deferred taxes of $641 for the three and six months ended October 31, 2021, respectively	2,465	0	1,892	0
Total Comprehensive Income	$ 4,868	$ 23,451	$ 7,649	$ 39,837