Investments - Additional Information (Detail) - USD ($) $ in Billions	Sep. 30, 2020	Jun. 30, 2020
Investments Debt And Equity Securities [Abstract]
Equity investments without readily determinable fair values measured at cost with adjustments for observable changes in price or impairments	$ 1.4	$ 1.4

Amount of investment in equity security without readily determinable fair value.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 321
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=120269885&loc=SL75117539-209714

Name:	us-gaap_EquitySecuritiesWithoutReadilyDeterminableFairValueAmount
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant