Other Comprehensive Income (Loss) (Accumulated Other Comprehensive Loss In Equity) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Income Tax Expense (Benefit)	$ 110,066	$ 103,216	$ 446,784	$ 292,162
Net income	210,607	187,558	826,455	536,673
Sales and other revenues	3,585,823	5,317,555	10,294,361	15,481,208
Operating Costs	265,398	280,957	775,159	826,577
Interest Expense	(11,102)	(11,038)	(31,813)	(33,521)
Net Income (Loss) Attributable to Noncontrolling Interest	(14,285)	(12,552)	(42,433)	(33,177)
Net of Tax and Noncontrolling Interest	196,322	175,006	784,022	503,496
General and Administrative Expense	(30,746)	(27,149)	(86,432)	(82,437)
Other comprehensive income (loss), net of tax	(5,681)	(4,756)	(21,204)	69,467
Income before income taxes	320,673	290,774	1,273,239	828,835
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	5,699	8,275	17,090	19,302
Reclassification out of Accumulated Other Comprehensive Income [Member] | Accumulated Net Investment Gain (Loss) Attributable to Parent [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Interest Income, Other	0	12	4	13
Income Tax Expense (Benefit)	0	5	18	5
Net income	0	7	28	8
Marketable Securities, Gain (Loss)			42	0
Income before income taxes			46	13
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 Tax Expense (Benefit)	3,598	5,384	10,772	12,345
Net income	5,380	8,190	16,101	18,555
Income (Loss) from Continuing Operations, Including Portion Attributable to Noncontrolling Interest	8,978	13,574	26,873	30,900
Net Income (Loss) Attributable to Noncontrolling Interest	(319)	(337)	(961)	(998)
Net of Tax and Noncontrolling Interest	5,699	8,527	17,062	19,553
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	57,513	(6,202)	156,445	(80,475)
Cost of Products Sold	(44,023)	20,776	(115,756)	111,217
Operating Costs	(3,986)	(444)	(12,231)	1,805
Reclassification out of Accumulated Other Comprehensive Income [Member] | Accumulated Net Gain (Loss) from Cash Flow Hedges Attributable to Parent [Member] | Interest Rate Swap [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Interest Expense	(526)	(556)	(1,585)	(1,647)
Reclassification out of Accumulated Other Comprehensive Income [Member] | Accumulated Defined Benefit Plans Adjustment Attributable to Parent [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Income Tax Expense (Benefit)	0	(163)
Net income	0	(259)
General and Administrative Expense	$ 0	$ (422)
Reclassification out of Accumulated Other Comprehensive Income [Member] | Accumulated Defined Benefit Plans Adjustment Attributable to Parent [Member] | Supplemental Employee Retirement Plan [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Income Tax Expense (Benefit)			0	(163)
Net income			0	(259)
General and Administrative Expense			$ 0	$ (422)