Related Party Transactions (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018	Sep. 30, 2018
Related Party Transactions [Abstract]
Net sales to related parties	$ 97	$ 94	$ 277	$ 303
Purchases from related parties	205	$ 157	555	$ 467
Accounts receivable due from related parties	77		77		$ 91
Accounts payable due to related parties	$ 115		$ 115		$ 102

For an unclassified balance sheet, amount of receivables arising from transactions with related parties.

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