Business Segments (Tables)

12 Months Ended

Dec. 31, 2013

Business Segments [Abstract]

Summary Of Information By Business Segment

Segment Information			Corporate and		Discontinued
(Thousands of dollars)	Marketing		Other Assets		Operations		Consolidated
Year ended December 31, 2013
Segment income (loss)	$	164,013		(7,687)		78,707	$	235,033
Revenues from external customers		17,814,081		269,254		-		18,083,335
Interest income		-		1,099		-		1,099
Interest expense		-		(14,509)		-		(14,509)
Income tax expense (benefit)		106,223		(4,872)		-		101,351
Significant noncash charges (credits)
Depreciation and amortization		71,253		2,877		-		74,130
Accretion of asset retirement obligations		1,096		-		-		1,096
Impairment of properties		-		-		-		-
Deferred and noncurrent income taxes (benefits)		(9,796)		2,534		-		(7,262)
Additions to property, plant and equipment		162,051		9,402		519		171,972
Total assets at year-end	$	1,527,125		354,117		-	$	1,881,242
Segment Information			Corporate and		Discontinued
(Thousands of dollars)	Marketing		Other Assets		Operations		Consolidated
Year ended December 31, 2012
Segment income (loss)	$	139,583		(53,169)		(2,846)	$	83,568
Revenues from external customers		19,011,040		290,268		-		19,301,308
Interest income		-		172		-		172
Interest expense		-		(384)		-		(384)
Income tax expense (benefit)		92,059		(28,354)		-		63,705
Significant noncash charges (credits)
Depreciation and amortization		66,913		4,827		-		71,740
Accretion of asset retirement obligations		980		-		-		980
Impairment of properties		-		60,988		-		60,988
Deferred and noncurrent income taxes (benefits)		3,393		(19,856)		-		(16,463)
Additions to property, plant and equipment		103,096		1,400		7,097		111,593
Total assets at year-end		1,765,020		111,025		116,420		1,992,465
Year ended December 31, 2011
Segment income (loss)	$	188,907		(1,054)		136,167	$	324,020
Revenues from external customers		18,702,720		216,496		-		18,919,216
Interest income		-		32		-		32
Interest expense		-		(408)		-		(408)
Income tax expense (benefit)		123,618		(658)		-		122,960
Significant noncash charges (credits)
Depreciation and amortization		61,135		3,744		-		64,879
Accretion of asset retirement obligations		877		-		-		877
Impairment of properties		-		-		-		-
Deferred and noncurrent income taxes (benefits)		22,686		262		-		22,948
Additions to property, plant and equipment		77,394		22,575		48,432		148,401
Total assets at year-end	$	1,524,898		150,403		109,682	$	1,784,983