Taxes on Earnings - Reconciliation of Unrecognized Tax Benefits (Details) - USD ($) $ in Millions	12 Months Ended
	Oct. 31, 2020	Oct. 31, 2019	Oct. 31, 2018
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns
Balance at beginning of year	$ 929	$ 7,771	$ 10,808
Increases:
For current year’s tax positions	59	79	66
For prior years’ tax positions	71	172	101
Decreases:
For prior years’ tax positions	(89)	(37)	(248)
Statute of limitations expirations	(2)	(15)	(3)
Settlements with taxing authorities	(148)	(7,041)	(2,953)
Balance at end of year	$ 820	$ 929	$ 7,771