Summary of Significant Accounting Policies Related Party Transactions (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Apr. 30, 2019	Apr. 30, 2018	Apr. 30, 2019	Apr. 30, 2018	Oct. 31, 2018
Traton Group [Member]
Related Party Transaction [Line Items]
Revenue from Related Parties	$ 42	$ 41	$ 71	$ 81
Costs and Expenses, Related Party	5	$ 8	18	$ 19
Accounts Receivable, Related Parties	16		16		$ 10
Accounts Payable, Related Parties	42		42		$ 25
Navistar Defense [Member]
Related Party Transaction [Line Items]
Revenue from Related Parties	28		34
Accounts Receivable, Related Parties	$ 40		$ 40

Amount for accounts payable to related parties.

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