Inventories - Inventories (Detail) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2014	Mar. 31, 2014
Inventory Disclosure [Abstract]
Finished goods	$ 641	$ 2,751
Work in process	7,213	5,932
Purchased and manufactured parts	15,164	13,155
Inventories, gross	23,018	21,838
Reserve for slow moving and obsolescence	(3,045)	(2,929)
Total	$ 19,973	$ 18,909