Supplementary Financial Information (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Mar. 31, 2014	Mar. 31, 2013	Mar. 31, 2012
Inventories
Materials and supplies	$ 1,320	$ 1,504
Work in process	175	105
Finished goods	1,051	856
Total inventories	2,546	2,465
Property and Equipment
Accumulated depreciation	(6,970)	(6,217)
Net	1,546	1,862
Depreciation expense	768	901	907
Equipment
Property and Equipment
Gross	6,541	6,126
Leasehold improvements
Property and Equipment
Gross	$ 1,975	$ 1,953