Employee Benefit Plans (Tables)

9 Months Ended

Sep. 30, 2020

Retirement Benefits [Abstract]

Schedule of Defined Benefit Plans Disclosures [Table Text Block]

Net periodic benefit cost (credit) for our pension and other postretirement plans consists of the following (in thousands):

	Pension Benefits				Other Postretirement Benefits
	Three Months Ended September 30,				Three Months Ended September 30,
	2020		2019		2020		2019
Components of Net Periodic Benefit Cost (Credit)
Service cost	$	2,779	$	2,409	$	93	$	82
Interest cost	5,710		6,622		123		152
Expected return on plan assets	(6,541)		(6,360)		(246)		(217)
Amortization of prior service cost (credit)	—		1,636		(471)		(471)
Recognized actuarial loss (gain)	1,257		—		(15)		(24)
Plan settlements	—		715		—		—
Net periodic benefit cost (credit)	$	3,205	$	5,022	$	(516)	$	(478)

	Pension Benefits				Other Postretirement Benefits
	Nine Months Ended September 30,				Nine Months Ended September 30,
	2020		2019		2020		2019
Components of Net Periodic Benefit Cost (Credit)
Service cost	$	8,337	$	7,228	$	278	$	248
Interest cost	17,130		19,866		369		457
Expected return on plan assets	(19,622)		(19,082)		(738)		(652)
Amortization of prior service cost (credit)	—		4,908		(1,412)		(1,412)
Recognized actuarial loss (gain)	3,771		—		(45)		(72)
Plan settlements	—		715		—		—
Net periodic benefit cost (credit)	$	9,616	$	13,635	$	(1,548)	$	(1,431)