Retirement and Post-Retirement Benefit Plans (Tables)
 6 Months Ended
Apr. 30, 2018
Retirement Benefits [Abstract]  
Summary of Net Benefit Cost
The Company's net pension benefit cost for defined benefit plans recognized in the Condensed Consolidated Statements of Earnings for the three and six months ended April 30, 2018 and 2017, was as follows:
 
Three months ended April 30,
 
Six months ended April 30,
 
2018
 
2017
 
2018
 
2017
 
In millions
Service cost
$
27

 
$
30

 
$
53

 
$
70

Interest cost
58

 
52

 
113

 
102

Expected return on plan assets
(145
)
 
(131
)
 
(284
)
 
(264
)
Amortization and deferrals:
 

 
 

 
 
 
 

Actuarial loss
54

 
64

 
106

 
140

Prior service benefit
(4
)
 
(4
)
 
(8
)
 
(8
)
Net periodic benefit (credit) cost
(10
)
 
11

 
(20
)
 
40

Settlement loss
2

 
3

 
2

 
3

Special termination benefits
2

 
1

 
4

 
2

Plan expense allocation(1)
—

 
(4
)
 
—

 
(16
)
Net benefit (credit) cost from continuing operations
(6
)
 
11

 
(14
)
 
29

Summary of net benefit (credit) cost:
 
 
 
 
 
 
 
Continuing operations
(6
)
 
11

 
(14
)
 
29

Discontinued operations
—

 
34

 
—

 
80

Net benefit (credit) cost
$
(6
)
 
$
45

 
$
(14
)
 
$
109

 
(1)
Plan expense allocation represents the net cost impact of employees of HPE covered under Everett or Seattle plans and employees of Everett or Seattle covered under HPE plans.