Income Taxes 5 (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Roll-forward of uncertain tax positions
Balance at beginning of year	$ 170us-gaap_UnrecognizedTaxBenefits	$ 382us-gaap_UnrecognizedTaxBenefits
Additions for tax positions related to the current year	16	20
Additions for tax positions from prior years	23	70
Reductions for tax positions from prior years	(43)	(233)
Settlement payments	(5)	(61)
Statute of limitations expiration	(13)	(11)
Translation and other	(14)	3
Balance at end of year	$ 134us-gaap_UnrecognizedTaxBenefits	$ 170us-gaap_UnrecognizedTaxBenefits

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Amount of unrecognized tax benefits pertaining to uncertain tax positions taken in tax returns.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

-Glossary Unrecognized Tax Benefit

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Amount of decrease in unrecognized tax benefits resulting from settlements with taxing authorities.

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Amount of increase in unrecognized tax benefits resulting from tax positions that have been or will be taken in current period tax return.

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Amount of increase in unrecognized tax benefits resulting from tax positions taken in prior period tax returns.

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Amount of decrease in unrecognized tax benefits resulting from lapses of applicable statutes of limitations.

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