Condensed Consolidated Statements of Comprehensive Income (Loss) (Unaudited) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Statement of Comprehensive Income [Abstract]
Net income (loss)	$ (4,998)	$ 7,194	$ (17,203)	$ (29,856)
Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent [Abstract]
Foreign currency translation gains (losses)	(689)	(4,466)	(7,075)	1,399
Defined benefit pension plans, net of tax impact	164	245	327	412
Post-retirement plan adjustments	(43)	(39)	(85)	(79)
Equity interest in NEC TOKIN’s other comprehensive income (loss)	(179)	(3,674)	(5,563)	(4,606)
Foreign exchange contracts	(841)	(770)	(1,706)	(3,717)
Other comprehensive income (loss)	(1,588)	(8,704)	(14,102)	(6,591)
Total comprehensive income (loss)	$ (6,586)	$ (1,510)	$ (31,305)	$ (36,447)