Other Financial Information (Noncash Operating Working Capital (Increase) Decrease) (Details) - USD ($) $ in Thousands	6 Months Ended
Jun. 30, 2020	Jun. 30, 2019
Net (increase) decrease in operating working capital, excluding cash and cash equivalents:
(Increase) decrease in accounts receivable	$ 227,710	$ (141,793)
(Increase) decrease in inventories	13,968	(617)
(Increase) decrease in prepaid expenses	(20,712)	(12,190)
Increase (decrease) in accounts payable and accrued liabilities	(219,228)	147,569
Increase (decrease) in income taxes payable	(403)	1,665
Net (increase) decrease in noncash operating working capital	1,335	(5,366)
Supplementary disclosures:
Cash income taxes paid, net of refunds	(7)	79
Interest paid, net of amounts capitalized of $4.9 million in 2020 and $0 million in 2019	100,745	102,802
Capitalized interest paid	4,900	0
Non-cash investing activities:
Asset retirement costs capitalized	6,342	38,396
(Increase) decrease in capital expenditure accrual	$ 58,602	(65,830)
Asset retirement obligations assumed		$ (37,300)

Business Combination, Recognized Identifiable Assets Acquired And Liabilities Assumed, Asset Retirement Obligations

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Amount of cash paid for interest capitalized, classified as investing activity.

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