Other Comprehensive Income (Accumulated Other Comprehensive Loss In Equity) (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2020	Mar. 31, 2020	Jun. 30, 2019	Mar. 31, 2019	Jun. 30, 2020	Jun. 30, 2019
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Sales and other revenues	$ 2,062,930		$ 4,782,615		$ 5,463,475	$ 8,679,862
Cost of products sold	1,576,996		3,704,884		4,270,722	6,904,089
Operating expenses	(303,359)		(333,252)		(631,704)	(664,844)
Income before income taxes	(181,318)		306,153		(636,770)	670,144
Income tax expense (benefit)	(30,911)		89,336		(193,077)	176,841
Other comprehensive income (loss), net of tax	14,374	$ (26,923)	2,804	$ 13,775	(12,549)	16,579
Reclassification out of Accumulated Other Comprehensive Income [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Other comprehensive income (loss), net of tax	(4,024)		3,964		875	5,187
Reclassification out of Accumulated Other Comprehensive Income [Member] \| Commodity Contract [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Sales and other revenues	(5,403)		0		49	(1,799)
Cost of products sold	459		5,674		2,289	9,295
Reclassification out of Accumulated Other Comprehensive Income [Member] \| Accumulated Net Gain (Loss) from Cash Flow Hedges Attributable to Parent [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Income before income taxes	(5,401)		5,321		1,175	6,963
Income tax expense (benefit)	(1,377)		1,357		300	1,776
Reclassification out of Accumulated Other Comprehensive Income [Member] \| Accumulated Net Gain (Loss) from Cash Flow Hedges Attributable to Parent [Member] \| Commodity Contract [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Sales and other revenues	(5,403)		0		49	(1,799)
Cost of products sold	459		5,674		2,289	9,295
Operating expenses	$ (457)		$ (353)		$ (1,163)	$ (533)

The aggregate costs related to goods produced and sold and services rendered by an entity during the reporting period. This excludes costs incurred during the reporting period related to financial services rendered and other revenue generating activities.

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