Expiration period of share based awards.

No definition available.

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- Definition

Share based compensation arrangement by share based payment award vesting rate.

+ References

No definition available.

+ Details

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- Details

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- Definition

Share Based Payment Award Vesting Rate based on targeted EBITDA

+ References

No definition available.

+ Details

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- Definition

Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (i)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

Unrecognized cost of unvested share-based awards, other than options, awarded to employees as compensation.

+ References

No definition available.

+ Details

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- Definition

Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (a)(1)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

+ Details

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- Definition

Amount of cash paid related to share-based compensation liabilities.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (d)(2)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

Description of pertinent provisions of equity-based compensation awards that have actual or potential impact upon the company's financial statements.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

+ Details

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Period Type:	duration

- Details

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- Details

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Share-Based Compensation (Details Textual) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Mar. 31, 2015	Mar. 31, 2014	Mar. 31, 2013
Share Based Compensation [Abstract]
Total share-based liabilities paid	$ 8	$ 15	$ 2
SARs [Member]
Share Based Compensation [Abstract]
Vesting rate	25.00%
Expiration period (years)	7 years
Terms of award	The amount of cash paid to settle Hindalco SARs and Novelis SARs are limited to two and a half or three times the target payout
SARs [Member] \| Hindalco SARs [Member]
Share Based Compensation [Abstract]
Terms of award	P6Y1M
Unrecognized compensation expense	9
Unrecognized compensation expense, weighted average period of recognition (years)	2 years 7 months
SARs [Member] \| Novelis SARs [Member]
Share Based Compensation [Abstract]
Terms of award	P6Y1M
Unrecognized compensation expense	13
Unrecognized compensation expense, weighted average period of recognition (years)	2 years 8 months
SARs [Member] \| Minimum [Member]
Share Based Compensation [Abstract]
Award vesting rate based on targeted EBITDA	75.00%
RSUs [Member]
Share Based Compensation [Abstract]
Terms of award	The payout on the RSUs is limited to three times the market value of one Hindalco share measured on the original date of grant.
Vesting period (years)	3 years
Total share-based liabilities paid	3	2
Unrecognized compensation expense	$ 18
Unrecognized compensation expense, weighted average period of recognition (years)	1 year 1 month