Property, Plant and Equipment (Details Textual) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Mar. 31, 2014	Mar. 31, 2013	Mar. 31, 2012
Property, Plant and Equipment [Line Items]
Fully depreciated assets	$ 752	$ 582
Capitalized interest costs	33	36	12
Asset impairment charges	24	4	46
Capital leases, term of contract	15 years
Evermore Joint Venture Exit [Member] | Asset Impairment [Member]
Property, Plant and Equipment [Line Items]
Asset impairment charges		4
Saguenay and Bridgenorth Plant Closure [Member]
Property, Plant and Equipment [Line Items]
Asset impairment charges			42
Long-lived Assets [Member]
Property, Plant and Equipment [Line Items]
Asset impairment charges	19
Non-core Assets [Member] | Brazil [Member]
Property, Plant and Equipment [Line Items]
Asset impairment charges	17		4
Other Long-lived Assets [Member]
Property, Plant and Equipment [Line Items]
Asset impairment charges	$ 2		$ 4