Financial Instruments and Fair Value Measurements - Summary of Hedges Classified as Current or Non-Current in Balance Sheets Based on Maturity Dates (Detail) - USD ($) $ in Millions	Sep. 30, 2018	Jun. 30, 2018
Foreign Currency Derivatives [Member] | Cash Flow Hedging [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivatives, reported under other current assets	$ 4	$ 3
Cross Currency Interest Rate Derivatives [Member] | Cash Flow Hedging [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivatives, reported under other current assets	30	0
Derivatives, reported under other non-current assets	61	76
Derivatives, reported under other current liabilities	(1)	0
Derivatives, reported under other non-current liabilities	(10)	(12)
Cross Currency Interest Rate Derivatives [Member] | Fair Value Hedging [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivatives, reported under other current assets	7	0
Derivatives, reported under other non-current assets	15	29
Cross Currency Interest Rate Derivatives [Member] | Not Designated as Hedging Instrument, Economic Hedge [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivatives, reported under other current assets	11	0
Derivatives, reported under other non-current assets	0	10
Interest Rate Contract [Member] | Cash Flow Hedging [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivatives, reported under other current liabilities	(1)	0
Derivatives, reported under other non-current liabilities	$ (17)	$ (20)