Redeemable Noncontrolling Interests - Schedule of Changes (Details) $ in Millions	6 Months Ended
Sep. 30, 2015 USD ($)
Redeemable Noncontrolling Interests
Beginning balance	$ 1,386
Net income attributable to noncontrolling interests	22
Other comprehensive income	24
Reclassification of recurring compensation to other accrued liabilities	(22)
Ending balance	$ 1,410

As of the reporting date, the carrying amount of noncontrolling interests which are redeemable by the (parent) entity (1) at a fixed or determinable price on a fixed or determinable date, (2) at the option of the holder of the noncontrolling interest, or (3) upon occurrence of an event that is not solely within the control of the (parent) entity. The noncontrolling interest holder's ownership (or holders' ownership) may be in the form of common shares (regardless of class), limited partnership units (regardless of class), non-preferential membership interests, or any other form of common equity regardless of investee entity legal form.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 480

-SubTopic 10

-Section S99

-Paragraph 3A

-Subparagraph (16)(c)

-URI http://asc.fasb.org/extlink&oid=27011957&loc=SL6540498-122764

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 480

-SubTopic 10

-Section S99

-Paragraph 3A

-Subparagraph (12)(c)

-URI http://asc.fasb.org/extlink&oid=27011957&loc=SL6540498-122764

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 480

-SubTopic 10

-Section S99

-Paragraph 3A

-Subparagraph 15

-URI http://asc.fasb.org/extlink&oid=27011957&loc=SL6540498-122764

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 480

-SubTopic 10

-Section S99

-Paragraph 3A

-Subparagraph 14

-URI http://asc.fasb.org/extlink&oid=27011957&loc=SL6540498-122764

Name:	us-gaap_RedeemableNoncontrollingInterestEquityCommonCarryingAmount
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant