Guarantees - Additional Information (Detail) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Jun. 30, 2019	Jun. 30, 2020
Guarantor Obligations [Line Items]
Maximum length, in years, of a product warranty for it to be recorded in other current liabilities		1 year
Minimum length, in years, of a product warranty for it to be recorded in other noncurrent liabilities		1 year
Release of tax indemnification reserve	$ 226

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

No definition available.

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