Debt (Short-Term Borrowings) (Details)												3 Months Ended				1 Months Ended		3 Months Ended			3 Months Ended
	Jun. 30, 2014 USD ($) Facilities	Mar. 31, 2014 USD ($)	May 31, 2013 Facilities	Jun. 30, 2014 First Korean Revolver [Member] USD ($)	Jun. 30, 2014 First Korean Revolver [Member] KRW	Jun. 30, 2014 Novelis Brazil Loan [Member] USD ($)	Jun. 30, 2014 Novelis Korea Bank Loan [Member] USD ($)	Jun. 30, 2014 Novelis Korea Bank Loan [Member] KRW	Jun. 30, 2014 Novelis Vietnam Loan [Member] USD ($)	Jun. 30, 2014 Novelis Vietnam Loan [Member] VND	Jun. 30, 2014 Bank Overdrafts [Member] USD ($)	Jun. 30, 2014 Novelis Korea Bank Loan Borrowing Capacity [Member] First Korean Revolver [Member] USD ($) Facilities	Jun. 30, 2014 Novelis Korea Bank Loan Borrowing Capacity [Member] First Korean Revolver [Member] KRW	Jun. 30, 2014 Novelis Korea Bank Loan Borrowing Capacity [Member] Second Korean Revolver [Member] USD ($)	Jun. 30, 2014 Novelis Korea Bank Loan Borrowing Capacity [Member] Second Korean Revolver [Member] KRW	Mar. 31, 2014 Novelis Korea Bank Loan Borrowing Capacity [Member] Third Korean Revolver [Member] USD ($)	Mar. 31, 2014 Novelis Korea Bank Loan Borrowing Capacity [Member] Third Korean Revolver [Member] KRW	Jun. 30, 2014 Novelis Korea Bank Loan Borrowing Capacity [Member] Third Korean Revolver [Member] USD ($) Facilities	Jun. 30, 2014 Novelis Korea Bank Loan Borrowing Capacity [Member] Fifth Korean Revolver [Member] USD ($)	Jun. 30, 2014 Novelis Korea Bank Loan Borrowing Capacity [Member] Fifth Korean Revolver [Member] KRW	Jun. 30, 2014 Novelis Korea Bank Loan Borrowing Capacity [Member] Fourth Korean Revolver [Member] USD ($)	Jun. 30, 2014 Novelis Korea Bank Loan Borrowing Capacity [Member] Fourth Korean Revolver [Member] KRW	Jun. 30, 2014 ABL Facility [Member] USD ($)	Jun. 30, 2014 ABL Facility [Member] Short-term Loan [Member] USD ($)
Short-term Debt [Line Items]
Short-term borrowings	$ 956,000,000	$ 723,000,000				$ 171,000,000	$ 57,000,000	58,000,000,000	$ 17,000,000	370,000,000,000	$ 1,000,000	$ 22,000,000	23,000,000,000	$ 49,000,000	50,000,000,000	$ 59,000,000	60,000,000,000		$ 30,000,000	30,000,000,000	$ 16,000,000	16,000,000,000		$ 710,000,000
Short-term debt, weighted average interest rate	3.58%
Letters of credit outstanding amount																							12,000,000
Remaining borrowing capacity																							278,000,000
Line of credit facility, number of instruments entered	2		2									1	1					1
Basis spread on variable rate												1.60%	1.60%	1.25%	1.25%	1.25%	1.25%	1.25%			1.60%	1.60%
Line of credit facility, amount outstanding	$ 0			$ 7,000,000	8,000,000,000													$ 0