Derivative Instruments, (Gain) Loss by Hedging Relationship, by Income Statement Location (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Mar. 31, 2015	Mar. 31, 2014	Mar. 31, 2013
Derivative Instruments, (Gain) Loss [Line Items]
Amount of Loss Recognized in AOCI	$ 0	$ 0	$ 0.5
Total Loss (Gain) Recognized in Continuing Operations	1.3	0.5	4.3
Reclassification out of Accumulated Other Comprehensive Income [Member]
Derivative Instruments, (Gain) Loss [Line Items]
Loss Reclassified from AOCI into Continuing Operations	0	0.5	2.6
Commodity Derivatives [Member]
Derivative Instruments, (Gain) Loss [Line Items]
Amount of Loss Recognized in AOCI	0	0	0.5
Foreign Exchange Contracts [Member]
Derivative Instruments, (Gain) Loss [Line Items]
Amount of Loss Recognized in AOCI	0		0
Cost of Sales [Member] | Commodity Derivatives [Member]
Derivative Instruments, (Gain) Loss [Line Items]
Total Loss (Gain) Recognized in Continuing Operations	0.2	0.5	4.6
Cost of Sales [Member] | Commodity Derivatives [Member] | Reclassification out of Accumulated Other Comprehensive Income [Member]
Derivative Instruments, (Gain) Loss [Line Items]
Loss Reclassified from AOCI into Continuing Operations	0	0.5	2.6
Other Income (Expense) - Net [Member] | Foreign Exchange Contracts [Member]
Derivative Instruments, (Gain) Loss [Line Items]
Total Loss (Gain) Recognized in Continuing Operations	1.1		(0.3)
Other Income (Expense) - Net [Member] | Foreign Exchange Contracts [Member] | Reclassification out of Accumulated Other Comprehensive Income [Member]
Derivative Instruments, (Gain) Loss [Line Items]
Loss Reclassified from AOCI into Continuing Operations	$ 0		$ 0