Employee Benefits (Tables)

9 Months Ended

Sep. 30, 2020

Retirement Benefits [Abstract]

Net Periodic Benefit Cost

The components of the net periodic benefit cost for our pension and postretirement benefit plans are as follows:

	Pension Plan				Postretirement Benefit Plan
Three Months Ended September 30,	2020		2019		2020		2019
Net periodic benefit cost
Service cost	$	2,707	$	1,997	$	432	$	456
Interest cost	2,066		2,080		253		319
Expected return on plan assets	(3,385)		(2,696)		—		—
Amortization of prior service credit	—		—		(2,021)		(2,221)
Amortization of net loss	979		901		94		224
Net periodic benefit cost	$	2,367	$	2,282	$	(1,242)	$	(1,222)

	Pension Plan				Postretirement Benefit Plan
Nine Months Ended September 30,	2020		2019		2020		2019
Net periodic benefit cost
Service cost	$	8,122	$	5,991	$	1,296	$	1,368
Interest cost	6,199		6,240		760		956
Expected return on plan assets	(10,154)		(8,088)		—		—
Amortization of prior service credit	—		—		(6,063)		(6,463)
Amortization of net loss	2,936		2,703		282		671
Net periodic benefit cost	$	7,103	$	6,846	$	(3,725)	$	(3,468)