Property, Plant and Equipment (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Mar. 31, 2014	Mar. 31, 2013	Mar. 31, 2012
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	$ 105,146	$ 100,870
Accumulated depreciation	(76,094)	(73,150)
Property, plant and equipment, net	29,052	27,720
Depreciation expense	6,187	5,386	5,434
Land
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	2,396	2,396
Building and improvements
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	31,384	30,823
Equipment and computer hardware and software
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	$ 71,366	$ 67,651