Investments - Additional Information (Detail) - USD ($) $ in Millions	3 Months Ended
Sep. 30, 2019	Sep. 30, 2018
Schedule of Investments [Abstract]
Equity losses of affiliates	$ (2)	$ (3)

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

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-Name Accounting Standards Codification
-Topic 942
-SubTopic 220
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04(13)(f))
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-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
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-Section 50
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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration