Share-Based Compensation (Tables)

12 Months Ended

Mar. 31, 2015

Disclosure of Compensation Related Costs, Share-based Payments [Abstract]

Total compensation expense related to SARs and RSUs under the long term incentive plans

Total compensation expense related to Hindalco SARs, Novelis SARs, and RSUs under the plans for the respective periods is presented in the table below (in millions). These amounts are included in “Selling, general and administrative expenses” or "Cost of goods sold (exclusive of depreciation and amortization)" in our consolidated statements of operations. As the performance criteria for fiscal years 2016, 2017 and 2018 have not yet been established, measurement periods for Hindalco SARs and Novelis SARs relating to those periods have not yet commenced. As a result, only compensation expense for vested and current year Hindalco SARs and Novelis SARs has been recorded.

	Year Ended March 31,
	2015		2014		2013
Total compensation expense (income)	$	9	$	27	$	(3	)

RSUs activity and SARs activity under LTIP

The table below shows the RSUs activity for the year ended March 31, 2015.

	Number of RSUs		Grant Date Fair Value (in Indian Rupees)	Aggregate Intrinsic Value (USD in millions)
RSUs outstanding as of March 31, 2014	4,490,860		120.42	$	11
Granted	1,913,537		145.81	—
Exercised	(748,108	)	181.20	3
Forfeited/Cancelled	(317,677	)	124.04	—
RSUs outstanding as of March 31, 2015	5,338,612		120.77	$	12

The table below shows Hindalco SARs activity for the year ended March 31, 2015.

	Number of Hindalco SARs		Weighted Average Exercise Price (in Indian Rupees)	Weighted Average Remaining Contractual Term (In years)	Aggregate Intrinsic Value (USD in millions)
SARs outstanding as of March 31, 2014	21,635,392		112.26	4.3	$	13
Granted	6,402,218		145.81	6.1	—
Exercised	(5,423,673	)	90.48	—	7
Forfeited/Cancelled	(1,437,380	)	129.29	—	—
SARs outstanding as of March 31, 2015	21,176,557		126.77	4.4	6
SARs exercisable as of March 31, 2015	6,917,124		126.61	2.6	$	3

The table below shows the Novelis SARs activity for the year ended March 31, 2015.

	Number of Novelis SARs		Weighted Average Exercise Price (in USD)		Weighted Average Remaining Contractual Term (In years)	Aggregate Intrinsic Value (USD in millions)
SARs outstanding as of March 31, 2014	668,402		$	90.09	5.3	$	2
Granted	495,030		94.40		6.1	—
Exercised	(55,554	)	80.09		—	1
Forfeited/Cancelled	(74,143	)	87.89		—	—
SARs outstanding as of March 31, 2015	1,033,735		$	92.85	5.2	3
SARs exercisable as of March 31, 2015	173,661		$	90.50	4.1	$	1

Assumptions used in estimating fair value of each SAR under LTIP

The fair value of each unvested Hindalco SAR was estimated using the following assumptions:

	Year ended March 31,
	2015		2014		2013
Risk-free interest rate	7.75% - 7.79%		8.67% - 8.96%		7.84% - 7.96%
Dividend yield	0.78	%	0.99	%	1.69	%
Volatility	39% - 46%		37% - 51%		37% - 52%

The fair value of each unvested Novelis SAR was estimated using the following assumptions:

	Year ended March 31,
	2015		2014		2013
Risk-free interest rate	0.96% - 1.59%		0.96% - 2.05%		—	%
Dividend yield	—	%	—	%	—	%
Volatility	27% - 34%		28% - 41%		—	%