XML 43 R31.htm IDEA: XBRL DOCUMENT v3.19.2
Employee Postretirement Benefits Employee Postretirement Benefits (Tables)
 6 Months Ended
Jul. 31, 2019
Retirement Benefits [Abstract]  
Components of net periodic benefit cost for postretirement plan The components of the net periodic benefit cost for postretirement benefits are as follows:
 
Three Months Ended
 
Six Months Ended
 
July 31,
2019
 
July 31,
2018
 
July 31,
2019
 
July 31,
2018
Service cost
$
7

 
$
7

 
$
14

 
$
14

Interest cost
84

 
79

 
167

 
158

Amortization of actuarial losses
24

 
32

 
48

 
64

Amortization of unrecognized gains in prior service cost
(40
)
 
(40
)
 
(80
)
 
(80
)
Net periodic benefit cost
$
75

 
$
78

 
$
149

 
$
156