Condensed Consolidated Statements of Comprehensive Income (Unaudited) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Oct. 31, 2020	Oct. 31, 2019	Oct. 31, 2020	Oct. 31, 2019
Statement of Comprehensive Income [Abstract]
Net income	$ 22,256	$ 22,163	$ 38,741	$ 49,044
Other comprehensive income, net of tax:
Change in pension benefits, net of deferred taxes of $111 and $108, and $224 and $215 for the three and six months ended October 31, 2020 and 2019, respectively	329	316	656	631
Total Comprehensive Income	$ 22,585	$ 22,479	$ 39,397	$ 49,675