Investment in NEC TOKIN - Summarized Financial Information (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2016	Dec. 31, 2015	Mar. 31, 2016
Schedule of Equity Method Investments [Line Items]
Document Period End Date			Dec. 31, 2016
NEC TOKIN Corporation [Member]
Equity Method Investment, Summarized Financial Information, Assets [Abstract]
Current assets	$ 248,128		$ 248,128		$ 240,427
Non-current assets	230,232		230,232		260,614
Equity Method Investment, Summarized Financial Information, Liabilities and Equity [Abstract]
Current liabilities	160,648		160,648		179,360
Non-current liabilities	322,768		322,768		$ 335,500
Equity Method Investment, Summarized Financial Information, Income Statement [Abstract]
Sales	127,845	$ 111,594	374,944	$ 343,686
Gross profit	28,886	24,610	82,487	74,333
Net income (loss) (1)	$ 1,082	$ (17,867)	$ 5,444	$ (10,606)