Retirement and Post-Retirement Benefit Plans (Details 3) - USD ($) $ in Millions	12 Months Ended
	Oct. 31, 2019	Oct. 31, 2018	Oct. 31, 2017
Post-Retirement Benefit Plans
Net benefit (credit) cost
Service cost	$ 1	$ 1	$ 3
Interest cost	7	7	6
Expected return on plan assets	(1)	(1)	(2)
Amortization and deferrals:
Actuarial loss (gain)	(4)	(3)	(2)
Prior service benefit	0	0	0
Net periodic benefit cost	3	4	5
Curtailment gain	0	0	0
Settlement loss	0	0	0
Special termination benefits	0	0	0
Plan credit allocation	0	0	(1)
Net benefit cost (credit) from continuing operations	3	4	4
Discontinued operations	0	0	1
Total net benefit (credit) cost	$ 3	$ 4	$ 5
Weighted average assumptions used to calculate net benefit (credit) cost
Discount rate used to determine benefit obligation	4.90%	4.50%	4.20%
Discount rate used to determine service cost	4.40%	3.70%	3.70%
Discount rate used to determine interest cost	4.70%	4.20%	3.80%
Expected increase in compensation levels	0.00%	0.00%	0.00%
Expected long-term return on plan assets	2.60%	2.60%	3.10%
Defined Benefit Plans
Net benefit (credit) cost
Service cost	$ 85	$ 105	$ 139
Interest cost	215	225	213
Expected return on plan assets	(511)	(567)	(548)
Amortization and deferrals:
Actuarial loss (gain)	235	211	264
Prior service benefit	(15)	(17)	(17)
Net periodic benefit cost	9	(43)	51
Curtailment gain	0	(1)	(1)
Settlement loss	13	20	15
Special termination benefits	2	6	5
Plan credit allocation	0	0	(14)
Net benefit cost (credit) from continuing operations	24	(18)	56
Discontinued operations	0	0	81
Total net benefit (credit) cost	$ 24	$ (18)	$ 137
Weighted average assumptions used to calculate net benefit (credit) cost
Discount rate used to determine benefit obligation	2.10%	2.00%	2.00%
Discount rate used to determine service cost	2.30%	2.40%	2.00%
Discount rate used to determine interest cost	1.80%	1.70%	1.80%
Expected increase in compensation levels	2.50%	2.30%	2.40%
Expected long-term return on plan assets	4.30%	4.40%	4.40%