Inventories (Tables)

6 Months Ended

Oct. 31, 2017

Inventory, Net [Abstract]

Components of Inventories

The components of inventories were: 

	October 31,			April 30,
(in thousands)	2017			2017
Raw materials	$	21,989		$	18,230
Work-in-process	18,605			18,704
Finished goods	19,576			19,372
Total FIFO inventories	60,170			56,306
Reserve to adjust inventories to LIFO value	(13,447		)	(13,447		)
Total LIFO inventories	$	46,723		$	42,859