Investment in NEC TOKIN (Details) (USD $)	9 Months Ended		9 Months Ended		3 Months Ended	9 Months Ended			0 Months Ended			9 Months Ended
	Dec. 31, 2013	Dec. 31, 2013 KEC Stockholders' Agreement	Dec. 31, 2013 NEC TOKIN	Feb. 01, 2013 NEC TOKIN Stockholders' Agreement director_position	Dec. 31, 2013 NEC TOKIN Put Option	Dec. 31, 2013 NEC TOKIN Put Option	Mar. 31, 2013 NEC TOKIN Put Option	Feb. 01, 2013 NEC TOKIN KEC	Feb. 01, 2013 NEC TOKIN KEC Stock Purchase Agreement	Mar. 12, 2012 NEC TOKIN KEC Stock Purchase Agreement	Feb. 01, 2013 NEC TOKIN KEC Stockholders' Agreement director_position	Dec. 31, 2013 NEC TOKIN KEC Option Agreement number_of_times	Dec. 31, 2013 NEC TOKIN KEC Put Option number_of_times
Investment in NEC TOKIN
Common stock acquired (as a percent)										51.00%
Economic ownership to be acquired (as a percent)										34.00%		49.00%
Purchase price paid									$ 50,000,000
Number of director positions				7							4
Purchase price for expected additional shares that may be acquired												50,000,000
Ownership interest maintained after acquisition of additional shares (as a percent)												51.00%
LTM EBITDA multiple												6	6
NEC TOKIN options, net					1,800,000	1,800,000	500,000
Gain recognized included in the Other expense, net	1,334,000				1,700,000	1,300,000
Purchase price								54,500,000
Transaction expenses								4,500,000
Summarized financial information
Current assets			243,029,000
Noncurrent assets			367,503,000
Current liabilities			122,120,000
Noncurrent liabilities			370,610,000
Net sales			387,905,000
Gross profit			68,748,000
Net income			11,286,000
Excess of the carrying value for its investment over equity in memo accounts			9,700,000
Net sales			3,700,000
Accounts receivable			1,300,000
Accounts payable			500,000
Receivable balances		$ 400,000