Discontinued Operations - Additional Information (Detail) (USD $)	1 Months Ended			6 Months Ended		12 Months Ended							1 Months Ended				12 Months Ended
	Sep. 30, 2011 OilRefinery	Mar. 31, 2011	Feb. 28, 2011	Dec. 31, 2012	Jun. 30, 2012	Dec. 31, 2013	Dec. 31, 2012		Dec. 31, 2011		Dec. 31, 2012 Ethanol Plant in Hereford, Texas [Member]	Dec. 31, 2013 Oil and Gas Properties [Member]	Aug. 30, 2013 Murphy USA Inc [Member]	Aug. 30, 2013 Murphy Oil USA Inc [Member]	Sep. 30, 2011 Superior Refinery [Member]	Sep. 30, 2011 Meraux Refinery [Member]	Dec. 31, 2013 U.K refining and marketing assets [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Common stock outstanding													100.00%
Percentage of ownership in Murphy USA Inc.														100.00%
Cash dividends distributed						$ 650,000,000	$ 0	[1]	$ 0	[1]				$ 650,000,000
Fund raised from proceeds of secured notes														500,000,000
Borrowed funds under credit facility														150,000,000
Provision of Specified Service Periods						The agreement provides for the provision of specified services, generally for a period of up to 18 months, with a possible extension of six months (an aggregate of 24 months), on a full cost basis.
After tax gain on sale of oil and natural gas production												216,147,000
Impairment charges of Investment											60,988,000						73,000,000
United Kingdom, corporation tax rate, tax relief on oil and gas decommissioning costs				50.00%	62.00%
United Kingdom, increase in tax expense of discontinued operations							5,523,000		14,461,000
United Kingdom, supplemental tax rate for oil and gas companies		62.00%	50.00%
Proceeds from sales of assets						1,650,000	99,000	[1]	27,382,000	[1]					214,000,000	325,000,000
Number of Refineries for disposal	2
Gain (loss) on disposal of refineries, net of tax	18,724,000														77,585,000	58,861,000
Gain (loss) on liquidation of inventories																$ 179,152,000

[1] Reclassified to conform to current presentation.