Inventories (Details) - USD ($) $ in Thousands	12 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Inventory [Line Items]
Raw material and components, cost	$ 8,104	$ 10,556
Raw materials and components, obsolescence reserve	(1,807)	(1,052)
Raw materials and components	6,297	9,504
Work in process, cost	1,918	2,045
Work in process, obsolescence reserve	(329)	(119)
Work in process	1,589	1,926
Finished goods, cost	7,044	6,550
Finished goods, obsolescence reserve	(1,337)	(956)
Finished goods	5,707	5,594
Total cost	17,066	19,151
Total obsolescence reserve	(3,473)	(2,127)
Total	13,593	$ 17,024
Increase in obsolescence reserve	1,346
Inventory Obsolescence Reserve
Inventory [Line Items]
Increase in obsolescence reserve	$ 1,671
Minimum
Inventory [Line Items]
Inventory consideration usage	9 months
Maximum
Inventory [Line Items]
Inventory consideration usage	24 months