Significant Accounting Policies Derivative Financial Instruments (Details) - USD ($) $ in Thousands	12 Months Ended
	Mar. 31, 2016	Mar. 31, 2015	Mar. 31, 2014
Cost of Sales [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (loss) on forward or option currency contracts	$ (2,001)	$ (3,123)	$ (1,468)