v2.4.0.8

Incentive Plans (Narrative) (Details) (USD $)	9 Months Ended			3 Months Ended	9 Months Ended
	Sep. 30, 2013 item	Sep. 30, 2012	Sep. 30, 2013 2013 Long-Term Incentive Plan [Member]	Sep. 30, 2013 2013 Stock Plan For Non-Employee Directors [Member]	Sep. 30, 2013 2013 Stock Plan For Non-Employee Directors [Member]	Sep. 30, 2013 Murphy Oil [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of share based compensation plans	2
Maximum number of shares authorized for incentive plan			10,000,000	500,000	500,000
Maximum number of shares per employee			1,000,000
Maximum amount payable			$ 5,000,000
Award vesting period					3 years	2 years
Restricted stock units issued				53,881
Restricted stock units issued, weighted average grant date fair value				$ 39.60
Share based compensation allocated	6,500,000	7,700,000
Compensation charged against income before income tax benefit	460,000	0
Income tax benefit related to share based compensation cost	161,000	0
Unrecognized compensation cost related to stock option awards	3,600,000
Unrecognized compensation cost related to stock option awards, weighted average period for recognition	1 year 10 months 24 days
Unrecognized compensation cost related to restricted stock awards	$ 12,100,000
Unrecognized compensation cost related to restricted stock awards, weighted average period of recognition	2 years 10 months 24 days

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Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

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The amount of expense, net of income tax, recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

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Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Unrecognized cost of unvested share-based awards, other than options, awarded to employees as compensation.

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Unrecognized cost of unvested options awarded to employees as compensation.

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The total recognized tax benefit related to compensation cost for equity-based payment arrangements recognized in income during the period.

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Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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Weighted average remaining contractual term for equity-based awards excluding options, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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The highest quantity of shares an employee can purchase under the plan per period.

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The maximum number of shares (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units remain authorized and become reserved for issuance under outstanding awards (not necessarily vested).

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