Location of Income (Expense) Recognized in Income on Derivative, Non-Designated Hedging Instruments (Details) (Interest and Other Income (Expense), net, USD $) In Millions, unless otherwise specified	3 Months Ended	6 Months Ended
Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Interest and Other Income (Expense), net
Derivative
Derivative Instruments Not Designated as Hedging Instruments, Income (Expense), Net	$ 18	$ (5)	$ 19	$ (5)

Amount of realized and unrealized gain (loss) of derivative instruments not designated or qualifying as hedging instruments.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 4C

-Subparagraph (e)

-URI http://asc.fasb.org/extlink&oid=35706170&loc=SL5624171-113959

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration