Summary of Significant Accounting Policies - Property, Plant and Equipment (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Mar. 31, 2015	Dec. 31, 2014
Property, Plant and Equipment [Line Items]
Property, plant and equipment	$ 125,101	$ 126,320	$ 127,491
Less - Accumulated depreciation and amortization	(98,509)	(100,827)	(101,716)
Net property, plant and equipment	26,592	25,493	25,775
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	34,363	35,664	35,445
Machinery, Equipment and Other [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment	$ 88,230	$ 88,148	$ 89,538