Derivative and Other Financial Instruments Foreign Currency Contracts (Details) (Foreign Exchange Contract [Member], Cost of Sales [Member], Fair Value Hedging [Member], USD $) In Thousands, unless otherwise specified	12 Months Ended
	Mar. 31, 2015	Mar. 31, 2014	Mar. 31, 2013
Foreign Exchange Contract [Member] | Cost of Sales [Member] | Fair Value Hedging [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) Recognized in Income	$ (3,123)	$ (1,468)	$ (14,287)