Fair Value Measurements (Details 3) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2014	Mar. 31, 2013
Expected realization of derivative instruments into earnings
Fiscal year ending March 31, 2015	$ 1,844
Fiscal year ending March 31, 2016 and beyond	(7,403)
Total	(5,559)	3,173
Energy Contracts
Expected realization of derivative instruments into earnings
Fiscal year ending March 31, 2015	(6)
Fiscal year ending March 31, 2016 and beyond	(7,949)
Total	(7,955)
Currency contracts
Expected realization of derivative instruments into earnings
Fiscal year ending March 31, 2015	1,850
Fiscal year ending March 31, 2016 and beyond	546
Total	$ 2,396