Share-based Compensation Arrangement by Share-based Payment Award, Target Payout Multiple

No definition available.

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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

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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

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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- Definition

Percentage of vesting of share-based compensation awards.

+ 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

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- Definition

Period from grant date that an equity-based award expires, 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)(2)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

+ Details

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- Details

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Share-Based Compensation (Details Textual) $ in Millions	12 Months Ended
Share-Based Compensation (Details Textual) $ in Millions	Mar. 31, 2017 USD ($)	Mar. 31, 2016 USD ($)	Mar. 31, 2015 USD ($)
Share-based Compensation by Award [Line Items]
Award vesting percentage	75.00%
Total share-based liabilities paid	$ 7	$ 2	$ 8
Minimum [Member]
Share-based Compensation by Award [Line Items]
Award target payout multiple	2.5
SARs [Member]
Share-based Compensation by Award [Line Items]
Award vesting percentage	25.00%
Award expiration period	7 years
SARs [Member] \| Hindalco SARs [Member]
Share-based Compensation by Award [Line Items]
Unrecognized compensation expense	$ 8
Unrecognized compensation expense, weighted average period of recognition (years)	1 year 6 months
SARs [Member] \| Novelis SARs [Member]
Share-based Compensation by Award [Line Items]
Unrecognized compensation expense	$ 1
Unrecognized compensation expense, weighted average period of recognition (years)	1 year 5 months
SARs [Member] \| Maximum [Member]
Share-based Compensation by Award [Line Items]
Award vesting percentage	33.00%
Award target payout multiple	3
RSUs [Member]
Share-based Compensation by Award [Line Items]
Vesting period (years)	3 years
Total share-based liabilities paid	$ 2	$ 5	$ 3
Unrecognized compensation expense	$ 11
Unrecognized compensation expense, weighted average period of recognition (years)	1 year
RSUs [Member] \| Maximum [Member]
Share-based Compensation by Award [Line Items]
Award target payout multiple	3