Stockholders' Equity - Components of Accumulated Other Comprehensive Loss, Net of Taxes (Details) $ in Millions	9 Months Ended
	Jul. 31, 2017 USD ($)
Components of accumulated other comprehensive loss, net of taxes
Balance at beginning of period	$ 31,518
Balance at end of period	29,050
Net unrealized gains (losses) on available-for-sale securities
Components of accumulated other comprehensive loss, net of taxes
Balance at beginning of period	54
Transfer related to the Everett Transaction	(9)
Other comprehensive (loss) income before reclassifications	(12)
Reclassifications of (gains) losses into earnings	0
Balance at end of period	33
Net unrealized gains (losses) on cash flow hedges
Components of accumulated other comprehensive loss, net of taxes
Balance at beginning of period	35
Transfer related to the Everett Transaction	0
Other comprehensive (loss) income before reclassifications	27
Reclassifications of (gains) losses into earnings	(196)
Balance at end of period	(134)
Unrealized components of defined benefit plans
Components of accumulated other comprehensive loss, net of taxes
Balance at beginning of period	(5,642)
Transfer related to the Everett Transaction	1,820
Other comprehensive (loss) income before reclassifications	662
Reclassifications of (gains) losses into earnings	169
Balance at end of period	(2,991)
Cumulative translation adjustment
Components of accumulated other comprehensive loss, net of taxes
Balance at beginning of period	(1,046)
Transfer related to the Everett Transaction	768
Other comprehensive (loss) income before reclassifications	10
Reclassifications of (gains) losses into earnings	0
Balance at end of period	(268)
Accumulated other comprehensive loss
Components of accumulated other comprehensive loss, net of taxes
Balance at beginning of period	(6,599)
Transfer related to the Everett Transaction	2,579
Other comprehensive (loss) income before reclassifications	687
Reclassifications of (gains) losses into earnings	(27)
Balance at end of period	$ (3,360)