Fair Value - Schedule of Assets and Liabilities on a Recurring Basis (Details) - Fair Value, Measurements, Recurring - USD ($) $ in Millions	Apr. 30, 2020	Oct. 31, 2019
Assets
Total assets	$ 4,469	$ 2,295
Liabilities
Total liabilities	91	147
Time deposits
Assets
Total assets	2,945	803
Money market funds
Assets
Total assets	521	859
Foreign bonds
Assets
Total assets	85	133
Other debt securities
Assets
Total assets	22	32
Interest rate contracts
Assets
Total assets	246	73
Liabilities
Total liabilities	5	11
Foreign exchange contracts
Assets
Total assets	641	392
Liabilities
Total liabilities	85	136
Other derivatives
Assets
Total assets	9	3
Liabilities
Total liabilities	1	0
Level 1
Assets
Total assets	521	866
Liabilities
Total liabilities	0	0
Level 1 | Time deposits
Assets
Total assets	0	0
Level 1 | Money market funds
Assets
Total assets	521	859
Level 1 | Foreign bonds
Assets
Total assets	0	7
Level 1 | Other debt securities
Assets
Total assets	0	0
Level 1 | Interest rate contracts
Assets
Total assets	0	0
Liabilities
Total liabilities	0	0
Level 1 | Foreign exchange contracts
Assets
Total assets	0	0
Liabilities
Total liabilities	0	0
Level 1 | Other derivatives
Assets
Total assets	0	0
Liabilities
Total liabilities	0	0
Level 2
Assets
Total assets	3,926	1,397
Liabilities
Total liabilities	91	147
Level 2 | Time deposits
Assets
Total assets	2,945	803
Level 2 | Money market funds
Assets
Total assets	0	0
Level 2 | Foreign bonds
Assets
Total assets	85	126
Level 2 | Other debt securities
Assets
Total assets	0	0
Level 2 | Interest rate contracts
Assets
Total assets	246	73
Liabilities
Total liabilities	5	11
Level 2 | Foreign exchange contracts
Assets
Total assets	641	392
Liabilities
Total liabilities	85	136
Level 2 | Other derivatives
Assets
Total assets	9	3
Liabilities
Total liabilities	1	0
Level 3
Assets
Total assets	22	32
Liabilities
Total liabilities	0	0
Level 3 | Time deposits
Assets
Total assets	0	0
Level 3 | Money market funds
Assets
Total assets	0	0
Level 3 | Foreign bonds
Assets
Total assets	0	0
Level 3 | Other debt securities
Assets
Total assets	22	32
Level 3 | Interest rate contracts
Assets
Total assets	0	0
Liabilities
Total liabilities	0	0
Level 3 | Foreign exchange contracts
Assets
Total assets	0	0
Liabilities
Total liabilities	0	0
Level 3 | Other derivatives
Assets
Total assets	0	0
Liabilities
Total liabilities	$ 0	$ 0