XML 45 R34.htm IDEA: XBRL DOCUMENT v3.7.0.1
Pension And Other Postretirement Benefits (Tables)
 3 Months Ended
Mar. 31, 2017
Pension and Other Postretirement Benefit Expense [Abstract]  
Components Of The Plans' Net Periodic Benefits Cost
The following tables provide the components of the plans’ actuarially determined net periodic benefit cost for the three months ended March 31, 2017 and 2016:

Pension Benefits
 
Other Postretirement
Benefits
Three Months Ended March 31, (in millions)
2017
 
2016
 
2017
 
2016
Components of Net Periodic Benefit Cost
 
 
 
 
 
 
 
Service cost(1)
$
7.5

 
$
7.7

 
$
1.2

 
$
1.2

Interest cost(1)
17.2

 
22.4

 
4.5

 
5.5

Expected return on assets
(30.3
)
 
(33.2
)
 
(4.0
)
 
(4.3
)
Amortization of prior service credit
(0.2
)
 
(0.1
)
 
(1.1
)
 
(1.2
)
Recognized actuarial loss
13.4

 
15.3

 
0.8

 
0.8

Total Net Periodic Benefit Cost
$
7.6

 
$
12.1

 
$
1.4

 
$
2.0

(1)Effective January 1, 2017, NiSource adopted the methodology of using a full yield curve (spot rate) approach to estimate the service and interest components of net periodic benefit cost. This change in accounting estimate resulted in a decrease in these costs for the three months ended March 31, 2017 when compared to the same period in 2016.