Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	12 Months Ended
	Apr. 30, 2022	Apr. 30, 2021	Apr. 30, 2020
Statement of Comprehensive Income [Abstract]
Net income (loss)	$ (29,722)	$ 61,193	$ 73,653
Other comprehensive income (loss), net of tax:
Change in pension benefits, net of deferred taxes of $(1,156), $(573), and $190, respectively	54,568	(3,395)	(1,682)
Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), Reclassification, after Tax	10,225	0	0
Total Comprehensive Income	$ 35,071	$ 57,798	$ 71,971