Supplemental Cash Flow Information (Net Changes in Components of Operating Assets and Liabilities) (Details) - USD ($)	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
(Increase) decrease in:
Accounts receivable	$ (120,916,000)	$ 17,511,000	$ 159,426,000
Inventories	(23,018,000)	38,824,000	(37,566,000)
Deferred charges	(19,662,000)	(14,742,000)	48,835,000
Other current assets	2,016,000	21,109,000	(2,110,000)
Increase (decrease) in:
Accounts payable	104,655,000	434,000	(135,289,000)
Accrued liabilities	(32,260,000)	(32,072,000)	(29,122,000)
Net changes in components of operating assets and liabilities	$ (89,185,000)	$ 31,064,000	$ 4,174,000