Condensed Consolidated Statements of Comprehensive Income (Unaudited) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Oct. 31, 2019	Oct. 31, 2018	Oct. 31, 2019	Oct. 31, 2018
Statement of Comprehensive Income [Abstract]
Net income	$ 22,163	$ 18,488	$ 49,044	$ 43,255
Other comprehensive income, net of tax:
Change in pension benefits, net of deferred taxes of $108 and $105, and $215 and $210 for the three and six months ended October 31, 2019 and 2018, respectively	316	307	631	614
Total Comprehensive Income	$ 22,479	$ 18,795	$ 49,675	$ 43,869