Derivative and Hedging Activities Derivative and Hedging Activities - Nondesignated Hedging (Details) - USD ($) $ in Millions	3 Months Ended
Jun. 30, 2019	Jun. 30, 2018
Other expense (income), net \| Foreign currency forward contracts \| Not Designated as Hedging Instrument
Derivative Instruments, Gain (Loss) [Line Items]
Pretax gain (loss) on derivative instruments	$ 19	$ 32

Aggregate net gain (loss) on all derivative instruments recognized in earnings during the period, before tax effects.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4A
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5618551-113959

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