Consolidated Statements of Comprehensive Income (Loss) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Jan. 31, 2019	Jan. 31, 2018	Jan. 31, 2019	Jan. 31, 2018
Net income (loss)	$ (32)	$ (2,851)	$ 84	$ (1,125)
Other comprehensive income, net of tax:
Decrease in pension liability, net of tax	157	225	471	674
Other comprehensive income	157	225	471	674
Total comprehensive income (loss)	$ 125	$ (2,626)	$ 555	$ (451)