Organization and Significant Accounting Policies (Details 4) (USD $)	12 Months Ended
	Mar. 31, 2014	Mar. 31, 2013	Mar. 31, 2012
Fair Value Measurement
Money markets	$ 714,000	$ 29,984,000
Total debt	398,589,000	383,500,000
Fair Value Net Forward Option Asset Liability Measured on Recurring Basis Unobservable Input Reconciliation [Roll Forward]
Change in value of NEC TOKIN option	3,111,000	0	0
Revenue Recognition
Percentage of total inventory purchased in previous quarter that can be returned by the distributors, maximum	6.00%
Period of product warranty	1 year
Warranty costs as a percentage of net sales, maximum (less than)	1.00%	1.00%	1.00%
Shipping and Handling Costs
Shipping and Handling Costs	19,900,000	21,100,000	22,800,000
Put Option | NEC TOKIN
Fair Value Measurement
NEC TOKIN options, net	3,600,000
Fair Value Net Forward Option Asset Liability Measured on Recurring Basis Unobservable Input Reconciliation [Roll Forward]
Change in value of NEC TOKIN option	3,100,000
Ending Balance	3,600,000
Carrying Value | Put Option | NEC TOKIN
Fair Value Measurement
NEC TOKIN options, net	3,600,000	489,000
Fair Value Net Forward Option Asset Liability Measured on Recurring Basis Unobservable Input Reconciliation [Roll Forward]
Ending Balance	3,600,000	489,000
Recurring
Fair Value Measurement
Money markets	714,000	29,984,000
Total debt	409,284,000	393,928,000
Recurring | Level 1
Fair Value Measurement
Money markets	714,000	29,984,000
Total debt	371,863,000	369,200,000
Recurring | Level 2
Fair Value Measurement
Total debt	37,421,000	24,728,000
Recurring | Level 3 | Put Option | NEC TOKIN
Fair Value Measurement
NEC TOKIN options, net	3,600,000
Fair Value Net Forward Option Asset Liability Measured on Recurring Basis Unobservable Input Reconciliation [Roll Forward]
Beginning Balance	489,000
Change in value of NEC TOKIN option	3,111,000
Ending Balance	$ 3,600,000