XML 32 R78.htm IDEA: XBRL DOCUMENT v2.4.1.9
Incentive Plans (Assumptions used in Valuation Performance Awards Granted) (Details) (Performance Based Restricted Stock [Member], USD $)
12 Months Ended
Dec. 31, 2014
item
Dec. 31, 2013
Dec. 31, 2012
item
Assumptions      
Expected volatility 29.00%us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityRate   37.00%us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityRate
Risk-free interest rate 0.65%us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRate   0.30%us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRate
Stock beta 0.843mur_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsStockBeta   0.913mur_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsStockBeta
Expected life 3 years 3 years 3 years
Minimum [Member]
     
Share based Compensation Arrangement by Share based Payment Award, Fair Value Assumptions, Method Used [Line Items]      
Granted restricted stock, fair value 33.90us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageGrantDateFairValue
/ us-gaap_AwardTypeAxis
= mur_PerformanceBasedRestrictedStockMember
/ us-gaap_RangeAxis
= us-gaap_MinimumMember
39.50us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageGrantDateFairValue
/ us-gaap_AwardTypeAxis
= mur_PerformanceBasedRestrictedStockMember
/ us-gaap_RangeAxis
= us-gaap_MinimumMember
54.90us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageGrantDateFairValue
/ us-gaap_AwardTypeAxis
= mur_PerformanceBasedRestrictedStockMember
/ us-gaap_RangeAxis
= us-gaap_MinimumMember
Assumptions      
Expected volatility   31.00%us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityRate
/ us-gaap_AwardTypeAxis
= mur_PerformanceBasedRestrictedStockMember
/ us-gaap_RangeAxis
= us-gaap_MinimumMember
 
Risk-free interest rate   0.41%us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRate
/ us-gaap_AwardTypeAxis
= mur_PerformanceBasedRestrictedStockMember
/ us-gaap_RangeAxis
= us-gaap_MinimumMember
 
Stock beta   0.907mur_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsStockBeta
/ us-gaap_AwardTypeAxis
= mur_PerformanceBasedRestrictedStockMember
/ us-gaap_RangeAxis
= us-gaap_MinimumMember
 
Maximum [Member]
     
Share based Compensation Arrangement by Share based Payment Award, Fair Value Assumptions, Method Used [Line Items]      
Granted restricted stock, fair value 51.30us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageGrantDateFairValue
/ us-gaap_AwardTypeAxis
= mur_PerformanceBasedRestrictedStockMember
/ us-gaap_RangeAxis
= us-gaap_MaximumMember
68.01us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageGrantDateFairValue
/ us-gaap_AwardTypeAxis
= mur_PerformanceBasedRestrictedStockMember
/ us-gaap_RangeAxis
= us-gaap_MaximumMember
63.64us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageGrantDateFairValue
/ us-gaap_AwardTypeAxis
= mur_PerformanceBasedRestrictedStockMember
/ us-gaap_RangeAxis
= us-gaap_MaximumMember
Assumptions      
Expected volatility   32.00%us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityRate
/ us-gaap_AwardTypeAxis
= mur_PerformanceBasedRestrictedStockMember
/ us-gaap_RangeAxis
= us-gaap_MaximumMember
 
Risk-free interest rate   0.62%us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRate
/ us-gaap_AwardTypeAxis
= mur_PerformanceBasedRestrictedStockMember
/ us-gaap_RangeAxis
= us-gaap_MaximumMember
 
Stock beta   0.908mur_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsStockBeta
/ us-gaap_AwardTypeAxis
= mur_PerformanceBasedRestrictedStockMember
/ us-gaap_RangeAxis
= us-gaap_MaximumMember