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	Dec. 31, 2019	Jun. 30, 2019
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	$ 0	$ 1
Derivatives, reported under other current liabilities	(2)	0
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	0	33
Derivatives, reported under other non-current assets	82	83
Derivatives, reported under other non-current liabilities	(17)	(18)
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	0	8
Derivatives, reported under other non-current assets	21	21
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	0	12
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	0	(2)
Derivatives, reported under other non-current liabilities	$ (16)	$ (18)