Investments - Additional Information (Detail) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2019	Dec. 31, 2018
Schedule of Investments [Abstract]
Equity losses of affiliates	$ 3	$ 6	$ 5	$ 9

Amount of income (loss) for proportionate share of equity method investee's income (loss).

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
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