Postretirement Benefits - Components of Postretirement Benefits Expense (Income) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Jan. 31, 2014	Jan. 31, 2013
Pension Plan, Defined Benefit [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Service cost for benefits earned during the period	$ 4	$ 5
Interest on obligation	39	36
Amortization of cumulative loss	24	32
Amortization of prior service benefit	0	0
Expected return on assets	(48)	(47)
Net postretirement benefits expense	19	26
Other Postretirement Benefit Plan, Defined Benefit [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Service cost for benefits earned during the period	1	2
Interest on obligation	17	15
Amortization of cumulative loss	4	7
Amortization of prior service benefit	(1)	(1)
Expected return on assets	(8)	(8)
Net postretirement benefits expense	$ 13	$ 15