Accounts Receivable - Summary of Accounts Receivable (Details) - USD ($) $ in Millions	Jun. 30, 2019	Oct. 01, 2018	Sep. 30, 2018
Receivables [Abstract]
Trade	$ 412		$ 390
Other	16		26
Accounts receivable, gross	428		416
Allowance for doubtful accounts	(5)		(7)
Total accounts receivable, net	$ 423	$ 376	$ 409

Amount, after allowance for credit loss, of right to consideration from customer for product sold and service rendered in normal course of business, classified as current.

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