Fair value measurement (Tables)

12 Months Ended

Dec. 31, 2023

Fair Value Disclosures [Abstract]

Schedule of Fair Value of Pension Plan Assets by Level within Fair Value Hierarchy

The below fair value tables relate to our TRP pension plan assets (in thousands):

Pension Plan Assets
Fair value measurement as of Dec. 31, 2023
	Level 1		Level 2		Level 3		Total
Assets:
Cash	$	87	$	—	$	—	$	87
Pension plan investments valued using net asset value as a practical expedient:
Common collective trust - equities							67,314
Common collective trust - fixed income							318,594
Partnership/joint venture interests							113
Total fair value of plan assets							$	386,108

Fair value measurement as of Dec. 31, 2022
	Level 1	Level 2	Level 3	Total
Pension plan investments valued using net asset value as a practical expedient:
Common collective trust - equities				$	54,917
Common collective trust - fixed income				329,821
Partnership/joint venture interests				267
Total fair value of plan assets				$	385,005