Investments - Additional Information (Detail) - USD ($) $ in Millions	3 Months Ended
Sep. 30, 2020	Sep. 30, 2019
Schedule of Investments [Abstract]
Equity losses of affiliates	$ 1	$ 2

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
Period Type:	duration