Postretirement Benefits - Schedule of Net Benefit (Details) - USD ($) $ in Millions	12 Months Ended
	Oct. 31, 2016	Oct. 31, 2015	Oct. 31, 2014
Defined Benefit Plan Disclosure [Line Items]
Net postretirement benefits expense	$ 153	$ 150	$ 160
Defined Benefit Plan, Benefits Paid	(15)
Pension and Other Postretirement Defined Benefit Plans, Liabilities, Noncurrent	(3,023)	(2,995)
Pension and Other Postretirement Defined Benefit Plans, Liabilities	(3,098)	(3,088)
Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Assets for Plan Benefits, Noncurrent	6	13
Defined Benefit Plan, Benefit Obligation	4,027	3,979	4,041
Service cost	(9)	(13)	(12)
Interest on obligations	118	142	158
Amortization of cumulative loss	104	97	94
Amortization of cumulative loss	0	1	0
Contractual termination benefits	3	(1)	23
Premiums on pension insurance	15	11	12
Expected return on assets	(167)	(194)	(193)
Net postretirement benefits expense	82	69	106
Defined Benefit Plan, Actuarial Gain (Loss)	225	146
Defined Benefit Plan, Special Termination Benefits	3	(1)
Defined Benefit Plan, Foreign Currency Exchange Rate Gain (Loss)	(7)	(53)
Defined Benefit Plan, Contributions by Plan Participants	0	0
Defined Benefit Plan, Gross Prescription Drug Subsidy Receipts Received	0	0
Defined Benefit Plan, Benefits Paid	(300)	(309)
Fair Value of Plan Assets	2,310	2,422	2,627
Defined Benefit Plan, Actual Return on Plan Assets	79	27
Defined Benefit Plan, Foreign Currency Exchange Rate Changes, Plan Assets	(6)	(51)
Defined Benefit Plan, Contributions by Employer	100	113
Defined Benefit Plan Change In Fair Value Of Plan Assets Benefits Paid	(285)	(294)
Defined Benefit Plan, Funded Status of Plan	(1,717)	(1,557)
Pension and Other Postretirement Defined Benefit Plans, Current Liabilities	(17)	(15)
Pension and Other Postretirement Defined Benefit Plans, Liabilities, Noncurrent	(1,706)	(1,555)
Pension and Other Postretirement Defined Benefit Plans, Liabilities	(1,717)	(1,557)
Pension and Other Postretirement Benefit Plans, Accumulated Other Comprehensive Income (Loss), Net Gains (Losses), before Tax	2,442	2,234
Pension and Other Postretirement Benefit Plans, Accumulated Other Comprehensive Income (Loss), Net Prior Service Cost (Credit), before Tax	0	0
Pension and Other Postretirement Benefit Plans, Accumulated Other Comprehensive Income (Loss), before Tax	2,442	2,234
Other Comprehensive Income (Loss), Pension and Other Postretirement Benefit Plans, Net Unamortized Gain (Loss) Arising During Period, before Tax	313	312	164
Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI, Pension and Other Postretirement Benefit Plans, for Net Gain (Loss), before Tax	(104)	(97)	(94)
Other Comprehensive (Income) Loss, Amortization Adjustment from AOCI, Pension and Other Postretirement Benefit Plans, for Net Prior Service Cost (Credit), before Tax	0	(1)	0
Other Comprehensive Income (Loss), Pension and Other Postretirement Benefit Plans, Currancy Translation Adjustment, before Tax	(1)	0	1
Other Comprehensive (Income) Loss, Pension and Other Postretirement Benefit Plans, Adjustment, before Tax	208	214	71
Net postretirement benefit expense (income) and other comprehensive loss (income)	290	283	177
Health and Life Insurance Benefits
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Assets for Plan Benefits, Noncurrent	0	0
Defined Benefit Plan, Benefit Obligation	1,708	1,887	1,957
Service cost	(5)	(6)	(5)
Interest on obligations	58	71	68
Amortization of cumulative loss	31	39	16
Amortization of cumulative loss	(1)	(4)	(4)
Contractual termination benefits	4	(1)	2
Premiums on pension insurance	0	0	0
Expected return on assets	(26)	(30)	(33)
Net postretirement benefits expense	71	81	54
Defined Benefit Plan, Actuarial Gain (Loss)	(138)	(34)
Defined Benefit Plan, Special Termination Benefits	4	(1)
Defined Benefit Plan, Foreign Currency Exchange Rate Gain (Loss)	0	0
Defined Benefit Plan, Contributions by Plan Participants	34	31
Defined Benefit Plan, Gross Prescription Drug Subsidy Receipts Received	37	40
Defined Benefit Plan, Benefits Paid	(179)	(183)
Fair Value of Plan Assets	333	369	415
Defined Benefit Plan, Actual Return on Plan Assets	3	3
Defined Benefit Plan, Foreign Currency Exchange Rate Changes, Plan Assets	0	0
Defined Benefit Plan, Contributions by Employer	2	2
Defined Benefit Plan Change In Fair Value Of Plan Assets Benefits Paid	(41)	(51)
Defined Benefit Plan, Funded Status of Plan	(1,375)	(1,518)
Pension and Other Postretirement Defined Benefit Plans, Current Liabilities	(58)	(78)
Pension and Other Postretirement Defined Benefit Plans, Liabilities, Noncurrent	(1,317)	(1,440)
Pension and Other Postretirement Defined Benefit Plans, Liabilities	(1,375)	(1,518)
Pension and Other Postretirement Benefit Plans, Accumulated Other Comprehensive Income (Loss), Net Gains (Losses), before Tax	472	618
Pension and Other Postretirement Benefit Plans, Accumulated Other Comprehensive Income (Loss), Net Prior Service Cost (Credit), before Tax	0	(1)
Pension and Other Postretirement Benefit Plans, Accumulated Other Comprehensive Income (Loss), before Tax	472	617
Other Comprehensive Income (Loss), Pension and Other Postretirement Benefit Plans, Net Unamortized Gain (Loss) Arising During Period, before Tax	(115)	(7)	326
Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI, Pension and Other Postretirement Benefit Plans, for Net Gain (Loss), before Tax	(31)	(39)	(16)
Other Comprehensive (Income) Loss, Amortization Adjustment from AOCI, Pension and Other Postretirement Benefit Plans, for Net Prior Service Cost (Credit), before Tax	1	4	4
Other Comprehensive Income (Loss), Pension and Other Postretirement Benefit Plans, Currancy Translation Adjustment, before Tax	0	0	0
Other Comprehensive (Income) Loss, Pension and Other Postretirement Benefit Plans, Adjustment, before Tax	(145)	(42)	314
Net postretirement benefit expense (income) and other comprehensive loss (income)	$ (74)	$ 39	$ 368