XML 30 R26.htm IDEA: XBRL DOCUMENT v3.20.1
Retirement plans (Tables)
 3 Months Ended
Mar. 31, 2020
Retirement Benefits [Abstract]  
Benefit Costs

Pension costs, which primarily include costs for the qualified TRP and the non-qualified SERP, are presented in the following table (in thousands):
 
Quarter ended Mar. 31,
 
2020
 
2019
 
 
 
 
Service cost-benefits earned during the period
$
2

 
$
—

Interest cost on benefit obligation
4,858

 
5,750

Expected return on plan assets
(7,750
)
 
(6,575
)
Amortization of prior service (credit) cost
(42
)
 
25

Amortization of actuarial loss
1,600

 
1,500

(Gains from) expense for company-sponsored retirement plans
$
(1,332
)
 
$
700