Benefit Plans and Other Postretirement Benefits
 9 Months Ended
Sep. 30, 2017
Retirement Benefits [Abstract]  
Benefit Plans and Other Postretirement Benefits
Benefit Plans and Other Postretirement Benefits

Components of Net Periodic Benefit Cost (Credit)
 
 
Three Months Ended Sept. 30
 
 
2017
 
2016
 
2017
 
2016
(Thousands of Dollars)
 
Pension Benefits
 
Postretirement Health
Care Benefits
Service cost
 
$
2,439

 
$
2,440

 
$
219

 
$
194

Interest cost
 
4,928

 
5,315

 
415

 
455

Expected return on plan assets
 
(6,971
)
 
(6,901
)
 
(589
)
 
(594
)
Amortization of prior service credit
 
—

 
—

 
(100
)
 
(100
)
Amortization of net loss (gain)
 
3,245

 
2,997

 
(155
)
 
(146
)
Net periodic benefit cost (credit)
 
3,641

 
3,851

 
(210
)
 
(191
)
Credits not recognized due to the effects of regulation
 
553

 
637

 
—

 
—

Net benefit cost (credit) recognized for financial reporting
 
$
4,194

 
$
4,488

 
$
(210
)
 
$
(191
)

 
 
 
 
 
 
 
 
 
 
 
Nine Months Ended Sept. 30
 
 
2017
 
2016
 
2017
 
2016
(Thousands of Dollars)
 
Pension Benefits
 
Postretirement Health
Care Benefits
Service cost
 
$
7,319

 
$
7,320

 
$
657

 
$
582

Interest cost
 
14,783

 
15,945

 
1,245

 
1,365

Expected return on plan assets
 
(20,913
)
 
(20,703
)
 
(1,767
)
 
(1,782
)
Amortization of prior service credit
 
—

 
—

 
(300
)
 
(300
)
Amortization of net loss (gain)
 
9,735

 
8,991

 
(465
)
 
(438
)
Net periodic benefit cost (credit)
 
10,924

 
11,553

 
(630
)
 
(573
)
Credits not recognized due to the effects of regulation
 
1,275

 
1,353

 
—

 
—

Net benefit cost (credit) recognized for financial reporting
 
$
12,199

 
$
12,906

 
$
(630
)
 
$
(573
)


In January 2017, contributions of $150.0 million were made across four of Xcel Energy’s pension plans, of which $23.0 million was attributable to SPS. Xcel Energy does not expect additional pension contributions during 2017.