Derivative Instruments - Fair Value (Details) - USD ($) $ in Millions	Jun. 30, 2017	Mar. 31, 2017
Designated as Hedging Instrument | Fair Value Hedging
Derivatives, Fair Value [Line Items]
Derivative asset, fair value	$ 31	$ 32
Derivative liability, fair value	2	1
Designated as Hedging Instrument | Fair Value Hedging | Interest Rate Swap | Other assets
Derivatives, Fair Value [Line Items]
Derivative asset, fair value	5	5
Designated as Hedging Instrument | Fair Value Hedging | Interest Rate Swap | Other long-term liabilities
Derivatives, Fair Value [Line Items]
Derivative liability, fair value	1	1
Designated as Hedging Instrument | Fair Value Hedging | Foreign Currency Forward Contracts | Other current assets
Derivatives, Fair Value [Line Items]
Derivative asset, fair value	26	27
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	0
Not Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Derivative asset, fair value	38	15
Derivative liability, fair value	7	12
Not Designated as Hedging Instrument | Foreign Currency Forward Contracts | Other current assets
Derivatives, Fair Value [Line Items]
Derivative asset, fair value	38	15
Not Designated as Hedging Instrument | Foreign Currency Forward Contracts | Accrued expenses and other current liabilities
Derivatives, Fair Value [Line Items]
Derivative liability, fair value	$ 7	$ 12