Derivative and Hedging Activities - Fair Value (Details) - USD ($) $ in Millions	Jun. 30, 2019	Mar. 31, 2019
Designated as Hedging Instrument | Fair Value Hedging
Derivatives, Fair Value [Line Items]
Derivative asset, fair value	$ 7	$ 38
Derivative liability, fair value	1	4
Designated as Hedging Instrument | Fair Value Hedging | Foreign currency forward contracts | Other current assets
Derivatives, Fair Value [Line Items]
Derivative asset, fair value	7	38
Designated as Hedging Instrument | Fair Value Hedging | Foreign currency forward contracts | Accrued expenses and other current liabilities
Derivatives, Fair Value [Line Items]
Derivative liability, fair value	1	4
Not Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Derivative asset, fair value	2	5
Derivative liability, fair value	2	9
Not Designated as Hedging Instrument | Foreign currency forward contracts | Other current assets
Derivatives, Fair Value [Line Items]
Derivative asset, fair value	2	5
Not Designated as Hedging Instrument | Foreign currency forward contracts | Accrued expenses and other current liabilities
Derivatives, Fair Value [Line Items]
Derivative liability, fair value	$ 2	$ 9