Inventories (Tables)

9 Months Ended

Jan. 31, 2016

Inventory, Net [Abstract]

Components of Inventories

The components of inventories were: 

	January 31,			April 30,
(in thousands)	2016			2015
Raw materials	$	18,236		$	17,199
Work-in-process	19,133			18,095
Finished goods	15,036			14,797
Total FIFO inventories	52,405			50,091
Reserve to adjust inventories to LIFO value	(14,309		)	(14,103		)
Total LIFO inventories	$	38,096		$	35,988