Financial Instruments and Fair Value Measurements - Summary of Mandatorily Redeemable Noncontrolling Interest Liabilities Classified Level 3 (Detail) - Financial Instruments Subject to Mandatory Redemption, Settlement Terms, Share Value [Member] - USD ($) $ in Millions	6 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Balance—beginning of period	$ 12	$ 79
Additions	0	12
Accretion	0	2
Balance—end of period	$ 12	$ 93