Stockholders' Equity - Components of Accumulated Other Comprehensive Loss, Net of Taxes (Details) $ in Millions	3 Months Ended
	Jan. 31, 2019 USD ($)
Components of accumulated other comprehensive loss, net of taxes
Balance at beginning of period	$ 21,274
Balance at end of period	18,335
Net unrealized gains (losses) on available-for-sale securities
Components of accumulated other comprehensive loss, net of taxes
Balance at beginning of period	17
Other comprehensive income (loss) before reclassifications	2
Reclassifications of (gains) losses into earnings	(3)
Balance at end of period	16
Net unrealized gains (losses) on cash flow hedges
Components of accumulated other comprehensive loss, net of taxes
Balance at beginning of period	106
Other comprehensive income (loss) before reclassifications	33
Reclassifications of (gains) losses into earnings	(117)
Balance at end of period	22
Unrealized components of defined benefit plans
Components of accumulated other comprehensive loss, net of taxes
Balance at beginning of period	(2,922)
Other comprehensive income (loss) before reclassifications	(45)
Reclassifications of (gains) losses into earnings	45
Balance at end of period	(2,922)
Cumulative translation adjustment
Components of accumulated other comprehensive loss, net of taxes
Balance at beginning of period	(419)
Other comprehensive income (loss) before reclassifications	9
Reclassifications of (gains) losses into earnings	0
Balance at end of period	(410)
Accumulated other comprehensive loss
Components of accumulated other comprehensive loss, net of taxes
Balance at beginning of period	(3,218)
Other comprehensive income (loss) before reclassifications	(1)
Reclassifications of (gains) losses into earnings	(75)
Balance at end of period	$ (3,294)