XML 39 R17.htm IDEA: XBRL DOCUMENT v3.8.0.1
Retirement Benefits
 3 Months Ended
Mar. 31, 2018
Defined Benefit Pension Plans and Defined Benefit Postretirement Plans Disclosure [Abstract]  
RETIREMENT BENEFITS
RETIREMENT BENEFITS
In March 2017, the FASB issued authoritative guidance that requires an entity to report, including on a retrospective basis, the non-service cost or income components of net benefit cost separately from the service cost component and outside of operating income. The Ameren Companies’ adoption of this guidance in the first quarter of 2018 resulted in the reclassification from "Operating Expenses – Other operations and maintenance" to “Other Income, Net” of first quarter 2017 net benefit income of $12 million, $6 million, and $3 million on Ameren's, Ameren Missouri's, and Ameren Illinois' respective statements of income.
The guidance also requires an entity to capitalize only the service cost component as part of an asset, such as inventory or property, plant, and equipment, on a prospective basis. Previously, all of the net benefit cost components were eligible for capitalization. This change in the capitalization of net benefit costs is not expected to affect our ability to recover total net benefit cost through customer rates.
The following table presents the components of the net periodic benefit cost (income), prior to capitalization, incurred for Ameren’s pension and postretirement benefit plans for the three months ended March 31, 2018 and 2017:
  
Pension Benefits
 
Postretirement Benefits
 
 
Three Months
 
Three Months
 
  
2018
 
2017
 
2018
 
2017
 
Service cost(a)
$
25

 
$
23

 
$
5

 
$
5

 
Non-service cost components:
 
 
 
 
 
 
 
 
Interest cost
42

 
45

 
11

 
12

 
Expected return on plan assets
(69
)
 
(66
)
 
(19
)
 
(19
)
 
Amortization of:
 
 
 
 
 
 
 
 
Prior service benefit
—

 
—

 
(1
)
 
(1
)
 
Actuarial loss (gain)
16

 
14

 
—

 
(2
)
 
Total non-service cost components(b)
(11
)
 
(7
)
 
(9
)
 
(10
)
 
Net periodic benefit cost (income)
$
14

 
$
16

 
$
(4
)
 
$
(5
)
 
(a)
Service cost, net of capitalization, is reflected in “Operating Expenses – Other operations and maintenance” on Ameren’s statement of income.
(b)
2018 amounts and the non-capitalized portion of 2017’s non-service cost components, as discussed above, are reflected in “Other Income, Net” on Ameren’s statement of income.
Ameren Missouri and Ameren Illinois are responsible for their respective shares of Ameren’s pension and postretirement costs. The following table presents the respective share of pension costs and the postretirement benefit costs (income) incurred for the three months ended March 31, 2018 and 2017:
  
Pension Benefits
 
Postretirement Benefits
 
 
Three Months
 
Three Months
 
  
2018
 
2017
 
2018
 
2017
 
Ameren Missouri(a)
$
5

 
$
6

 
$
—

 
$
(1
)
 
Ameren Illinois
9

 
10

 
(4
)
 
(4
)
 
Ameren(a)
$
14

 
$
16

 
$
(4
)
 
$
(5
)
 

(a)
Does not include the impact of the regulatory tracking mechanism for the difference between the level of pension and postretirement benefit costs incurred by Ameren Missouri under GAAP and the level of such costs included in rates.