Summary of Significant Accounting Policies - Property, Plant and Equipment (Details) - USD ($) $ in Thousands	Jun. 30, 2016	Mar. 31, 2016	Jun. 30, 2015
Property, Plant and Equipment [Line Items]
Property, plant and equipment	$ 125,785	$ 124,500	$ 127,685
Less - Accumulated depreciation and amortization	(98,696)	(97,447)	(102,175)
Net property, plant and equipment	27,089	27,053	25,510
Land [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment	2,508	2,508	2,508
Buildings, Leasehold Interests and Improvements [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment	34,610	34,317	35,879
Machinery, Equipment and Other [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment	$ 88,667	$ 87,675	$ 89,298