Stockholders' Deficit - Schedule of Accumulated Other Comprehensive Loss, Net of Taxes (Details) - USD ($) $ in Millions	3 Months Ended
	Jan. 31, 2018	Jan. 31, 2017
Components of accumulated other comprehensive income, net of taxes
Balance at beginning of period	$ (3,408)
Other comprehensive loss before reclassifications	(483)
Reclassifications of (gains) losses into earnings	71
Reclassifications of curtailments and settlements into earnings	1
Balance at end of period	(2,742)
Accumulated other comprehensive loss
Components of accumulated other comprehensive income, net of taxes
Balance at beginning of period	(1,418)
Balance at end of period	(1,829)
Net unrealized gains on available-for-sale securities
Components of accumulated other comprehensive income, net of taxes
Balance at beginning of period	12
Other comprehensive loss before reclassifications	(2)
Reclassifications of (gains) losses into earnings	(5)
Reclassifications of curtailments and settlements into earnings	0
Balance at end of period	5
Net unrealized gains (losses) on cash flow hedges
Components of accumulated other comprehensive income, net of taxes
Balance at beginning of period	(240)
Other comprehensive loss before reclassifications	(481)	$ (172)
Reclassifications of (gains) losses into earnings	67	$ (67)
Reclassifications of curtailments and settlements into earnings	0
Balance at end of period	(654)
Unrealized components of defined benefit plans
Components of accumulated other comprehensive income, net of taxes
Balance at beginning of period	(1,190)
Other comprehensive loss before reclassifications	0
Reclassifications of (gains) losses into earnings	9
Reclassifications of curtailments and settlements into earnings	1
Balance at end of period	$ (1,180)