Debt (Other Long-term Debt) (Details) In Millions, unless otherwise specified	1 Months Ended		12 Months Ended			1 Months Ended
	Dec. 31, 2004 USD ($)	Dec. 31, 2004 CHF	Mar. 31, 2015 USD ($)	Mar. 31, 2014 Information Technology [Member]	Mar. 31, 2015 Other Capital Leases [Member] USD ($)	Dec. 31, 2004 Alcan [Member]
Debt Instrument [Line Items]
Capital leases, term of contract			15 years	5 years		15 years
Interest rate						7.50%
Quarterly capital lease payments	$ 1.8	1.7
Principal obligation on capital leases			$ 36		$ 5