Pension plans and other postretirement benefits (Tables)

6 Months Ended

Jun. 30, 2022

Compensation And Retirement Disclosure [Abstract]

Net Periodic Defined Benefit Cost for Defined Benefit Plans

Net periodic defined benefit cost for defined benefit plans consisted of the following:

	Pension Benefits						Other Postretirement Benefits
	Three Months Ended June 30
	2022			2021			2022			2021
	(In thousands)
Service cost	$	4,543		$	5,234		$	993		$	258
Interest cost on projected benefit obligation		22,080			15,502			671			329
Expected return on plan assets		(50,083	)		(35,774	)		—			—
Amortization of prior service cost (credit)		133			151			(311	)		(1,194	)
Amortization of net actuarial loss (gain)		5,322			22,359			(416	)		(347	)
Net periodic cost (benefit)	$	(18,005	)	$	7,472		$	937		$	(954	)
	Pension Benefits						Other Postretirement Benefits
	Six Months Ended June 30
	2022			2021			2022			2021
	(In thousands)
Service cost	$	8,814		$	10,257		$	1,225		$	506
Interest cost on projected benefit obligation		38,347			30,936			1,026			656
Expected return on plan assets		(87,233	)		(71,724	)		—			—
Amortization of prior service cost (credit)		258			276			(1,386	)		(2,369	)
Amortization of net actuarial loss (gain)		9,947			44,509			(741	)		(647	)
Net periodic cost (benefit)	$	(29,867	)	$	14,254		$	124		$	(1,854	)