XML 120 R22.htm IDEA: XBRL DOCUMENT v2.4.0.8
Components of net periodic benefit cost
 6 Months Ended
Jun. 30, 2013
Components of net periodic benefit cost [Abstract]  
Components of net periodic benefit cost
Components of net periodic benefit cost
 
Pension Benefits
 
Three months ended June 30,

Six months ended June 30,
 
2013
2012

2013
2012
Service cost
$
926

$
506

 
$
1,606

$
1,401

Interest cost
1,755

1,606

 
3,390

3,436

Expected return on plan assets
(1,893
)
(1,782
)
 
(3,613
)
(3,482
)
Amortization of prior service cost
22

34

 
54

69

Amortization of net loss
857

1,133

 
1,706

1,821

Curtailment
(18
)
—

 
(18
)
—

Net periodic benefit cost
$
1,649

$
1,497

 
$
3,125

$
3,245

 
Other Postretirement Benefits ("OPEB")
 
Three months ended June 30,
 
Six months ended June 30,
 
2013
2012
 
2013
2012
Service cost
$
670

$
370

 
$
1,163

$
895

Interest cost
1,433

1,271

 
2,756

2,757

Amortization of prior service cost
(938
)
(1,065
)
 
(1,998
)
(2,125
)
Amortization of net loss
1,273

1,808

 
2,776

3,304

Curtailment
(20
)
—

 
(20
)
—

Net periodic benefit cost
$
2,418

$
2,384

 
$
4,677

$
4,831



Employer contributions
During the six months ended June 30, 2013, we have made contributions of approximately $7,419 to the qualified defined benefit plans we sponsor.