Revenue and Assets by Geographic Segment (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Mar. 31, 2014	Mar. 31, 2013	Mar. 31, 2012
Segment Reporting Information [Line Items]
Amount of identifiable long-lived assets (consisting of property, plant and equipment)	$ 531,967	$ 514,544
Future electronics [Member]
Geographic Areas, Revenues from External Customers [Abstract]
Percentage of net sales to unaffiliated customers			10.00%
United States [Member]
Segment Reporting Information [Line Items]
Amount of identifiable long-lived assets (consisting of property, plant and equipment)	311,926	325,326
Thailand [Member]
Segment Reporting Information [Line Items]
Amount of identifiable long-lived assets (consisting of property, plant and equipment)	179,139	171,100
Various Other Countries besides United States and Thailand [Member]
Segment Reporting Information [Line Items]
Amount of identifiable long-lived assets (consisting of property, plant and equipment)	$ 40,902	$ 18,118
Located outside US, in aggregate [Member]
Geographic Areas, Revenues from External Customers [Abstract]
Percentage of net sales to unaffiliated customers	84.00%	83.00%	82.00%
Europe [Member]
Geographic Areas, Revenues from External Customers [Abstract]
Percentage of net sales to unaffiliated customers	21.00%	22.00%	23.00%
Asia [Member]
Geographic Areas, Revenues from External Customers [Abstract]
Percentage of net sales to unaffiliated customers	60.00%	58.00%	56.00%
China, including Hong-Kong [Member]
Geographic Areas, Revenues from External Customers [Abstract]
Percentage of net sales to unaffiliated customers	29.00%	27.00%	24.00%
Taiwan [Member]
Geographic Areas, Revenues from External Customers [Abstract]
Percentage of net sales to unaffiliated customers	13.00%	13.00%	15.00%