Other Financial Information (Details) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023
Net (increase) decrease in operating working capital, excluding cash and cash equivalents:
(Increase) decrease in accounts receivable	$ 7,355	$ (18,915)
(Increase) decrease in inventories	2,170	(8,353)
Decrease in prepaid expenses	2,296	8,291
Increase (decrease) in accounts payable and accrued liabilities	(9,689)	6,642
Increase (decrease) in income taxes payable	(1,006)	(3,005)
Net decrease (increase) in noncash working capital	1,126	(15,340)
Supplementary disclosures:
Cash income taxes paid, net of refunds	3,236	10,904
Interest paid, net of amounts capitalized of $7.8 million in 2024 and $6.8 million in 2023	38,262	54,305
Non-cash investing activities:
Asset retirement costs capitalized	16,175	2,742
(Increase) decrease in capital expenditure accrual	(24,780)	20,522
Interest paid, amount capitalized	$ 7,800	$ 6,800