Employee benefit plans (Tables)

9 Months Ended

Sep. 30, 2025

Retirement Benefits [Abstract]

Schedule of Components of Net Periodic Benefit Cost

Components of net periodic benefit cost for the Company's pension benefit plans were as follows:

	Three Months Ended				Nine Months Ended
	September 30,				September 30,
	2025		2024		2025		2024
	(In thousands)
Components of net periodic benefit cost:
Interest cost	$	3,303	$	3,200	$	9,909	$	9,600
Expected return on assets	(3,645)		(4,028)		(10,935)		(12,084)
Amortization of net actuarial loss	1,193		1,037		3,580		3,111
Net periodic benefit cost	$	851	$	209	$	2,554	$	627

Components of net periodic benefit credit for the Company's other postretirement benefit plans were as follows:

	Three Months Ended				Nine Months Ended
	September 30,				September 30,
	2025		2024		2025		2024
	(In thousands)
Components of net periodic benefit credit:
Service cost	$	99	$	126	$	297	$	378
Interest cost	462		459		1,386		1,377
Expected return on assets	(1,292)		(1,329)		(3,876)		(3,987)
Amortization of prior service credit	(290)		(330)		(869)		(990)
Amortization of net actuarial gain	(80)		(72)		(240)		(216)
Net periodic benefit credit, including amount capitalized	(1,101)		(1,146)		(3,302)		(3,438)
Less amount capitalized	18		25		54		72
Net periodic benefit credit	$	(1,119)	$	(1,171)	$	(3,356)	$	(3,510)