Other Financial Information (Noncash Operating Working Capital (Increase) Decrease) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Net decrease (increase) in operating working capital, excluding cash and cash equivalents:
(Increase) in accounts receivable	$ (117,928)	$ (16,954)
(Increase) decrease in inventories	(4,541)	392
(Increase) in prepaid expenses	(515)	(3,652)
Increase in accounts payable and accrued liabilities	40,426	11,810
Increase (decrease) in income taxes payable	1,636	(648)
Net (increase) in noncash operating working capital	(80,922)	(9,052)
Supplementary disclosures:
Cash income taxes paid, net of refunds	103	720
Interest paid, net of amounts capitalized of $5.3 million in 2022 and $3.3 million in 2021	40,181	44,577
Capitalized interest paid	5,300	3,300
Non-cash investing activities:
Asset retirement costs capitalized	3,889	6,390
(Increase) decrease in capital expenditure accrual	$ (49,352)	13,617
Impairment of asset retirement obligation		$ 74,400