XML 28 R40.htm IDEA: XBRL DOCUMENT v2.4.1.9
Fair Value Measurements (Details) (USD $)
In Thousands, unless otherwise specified
Mar. 31, 2015
Dec. 31, 2014
Assets:    
Derivative assets not designated as hedging instruments $ 585,474us-gaap_DerivativeFairValueOfDerivativeAsset $ 592,208us-gaap_DerivativeFairValueOfDerivativeAsset
Proved Oil and Gas Property, Successful Effort Method 7,006,832us-gaap_ProvedOilAndGasPropertySuccessfulEffortMethod 7,348,436us-gaap_ProvedOilAndGasPropertySuccessfulEffortMethod
Disposal Group, Including Discontinued Operation, Long Lived Assets, Current 184,951us-gaap_DisposalGroupIncludingDiscontinuedOperationLongLivedAssetsCurrent 17,891us-gaap_DisposalGroupIncludingDiscontinuedOperationLongLivedAssetsCurrent
Liabilities:    
Derivatives (398)us-gaap_DerivativeFairValueOfDerivativeLiability (70)us-gaap_DerivativeFairValueOfDerivativeLiability
Deferred Compensation Cash-based Arrangements, Liability, Classified, Noncurrent 22,802us-gaap_DeferredCompensationCashbasedArrangementsLiabilityClassifiedNoncurrent 27,136us-gaap_DeferredCompensationCashbasedArrangementsLiabilityClassifiedNoncurrent
Asset Retirement Obligations, Noncurrent 14,286sm_AssetRetirementObligationsAssetsHeldForSaleNoncurrent 438sm_AssetRetirementObligationsAssetsHeldForSaleNoncurrent
Fair Value, Measurements, Nonrecurring [Member] | Fair Value, Inputs, Level 1 [Member]    
Assets:    
Proved Oil and Gas Property, Successful Effort Method 0us-gaap_ProvedOilAndGasPropertySuccessfulEffortMethod
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel1Member
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsNonrecurringMember		 [1] 0us-gaap_ProvedOilAndGasPropertySuccessfulEffortMethod
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel1Member
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsNonrecurringMember		 [2]
Disposal Group, Including Discontinued Operation, Long Lived Assets, Current 0us-gaap_DisposalGroupIncludingDiscontinuedOperationLongLivedAssetsCurrent
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel1Member
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsNonrecurringMember		 [1] 0us-gaap_DisposalGroupIncludingDiscontinuedOperationLongLivedAssetsCurrent
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel1Member
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsNonrecurringMember		 [2]
Liabilities:    
Asset Retirement Obligations, Noncurrent 0sm_AssetRetirementObligationsAssetsHeldForSaleNoncurrent
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel1Member
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsNonrecurringMember		 [1]  
Fair Value, Measurements, Nonrecurring [Member] | Fair Value, Inputs, Level 2 [Member]    
Assets:    
Proved Oil and Gas Property, Successful Effort Method 0us-gaap_ProvedOilAndGasPropertySuccessfulEffortMethod
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel2Member
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsNonrecurringMember		 [1] 0us-gaap_ProvedOilAndGasPropertySuccessfulEffortMethod
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel2Member
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsNonrecurringMember		 [2]
Disposal Group, Including Discontinued Operation, Long Lived Assets, Current 0us-gaap_DisposalGroupIncludingDiscontinuedOperationLongLivedAssetsCurrent
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel2Member
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsNonrecurringMember		 [1] 0us-gaap_DisposalGroupIncludingDiscontinuedOperationLongLivedAssetsCurrent
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel2Member
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsNonrecurringMember		 [2]
Liabilities:    
Asset Retirement Obligations, Noncurrent 0sm_AssetRetirementObligationsAssetsHeldForSaleNoncurrent
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel2Member
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsNonrecurringMember		 [1]  
Fair Value, Measurements, Nonrecurring [Member] | Fair Value, Inputs, Level 3 [Member]    
Assets:    
Proved Oil and Gas Property, Successful Effort Method 48,969us-gaap_ProvedOilAndGasPropertySuccessfulEffortMethod
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel3Member
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsNonrecurringMember		 [1] 33,423us-gaap_ProvedOilAndGasPropertySuccessfulEffortMethod
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel3Member
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsNonrecurringMember		 [2]
Disposal Group, Including Discontinued Operation, Long Lived Assets, Current 58,779us-gaap_DisposalGroupIncludingDiscontinuedOperationLongLivedAssetsCurrent
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel3Member
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsNonrecurringMember		 [1] 17,891us-gaap_DisposalGroupIncludingDiscontinuedOperationLongLivedAssetsCurrent
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel3Member
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsNonrecurringMember		 [2]
Liabilities:    
Asset Retirement Obligations, Noncurrent 9,509sm_AssetRetirementObligationsAssetsHeldForSaleNoncurrent
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel3Member
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsNonrecurringMember		 [1]  
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 1 [Member]    
Liabilities:    
Deferred Compensation Cash-based Arrangements, Liability, Classified, Noncurrent 0us-gaap_DeferredCompensationCashbasedArrangementsLiabilityClassifiedNoncurrent
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel1Member
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember		 [3] 0us-gaap_DeferredCompensationCashbasedArrangementsLiabilityClassifiedNoncurrent
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel1Member
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember		 [3]
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member]    
Liabilities:    
Deferred Compensation Cash-based Arrangements, Liability, Classified, Noncurrent 0us-gaap_DeferredCompensationCashbasedArrangementsLiabilityClassifiedNoncurrent
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel2Member
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember		 [3] 0us-gaap_DeferredCompensationCashbasedArrangementsLiabilityClassifiedNoncurrent
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel2Member
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember		 [3]
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 3 [Member]    
Liabilities:    
Deferred Compensation Cash-based Arrangements, Liability, Classified, Noncurrent 22,802us-gaap_DeferredCompensationCashbasedArrangementsLiabilityClassifiedNoncurrent
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel3Member
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember		 [3] 27,136us-gaap_DeferredCompensationCashbasedArrangementsLiabilityClassifiedNoncurrent
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel3Member
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember		 [3]
Derivatives not designated as hedging instruments | Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 1 [Member]    
Assets:    
Derivative assets not designated as hedging instruments 0us-gaap_DerivativeFairValueOfDerivativeAsset
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel1Member
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
/ us-gaap_HedgingDesignationAxis
= us-gaap_NondesignatedMember		 [3] 0us-gaap_DerivativeFairValueOfDerivativeAsset
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel1Member
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
/ us-gaap_HedgingDesignationAxis
= us-gaap_NondesignatedMember		 [3]
Liabilities:    
Derivatives 0us-gaap_DerivativeFairValueOfDerivativeLiability
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel1Member
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
/ us-gaap_HedgingDesignationAxis
= us-gaap_NondesignatedMember		 [3] 0us-gaap_DerivativeFairValueOfDerivativeLiability
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel1Member
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
/ us-gaap_HedgingDesignationAxis
= us-gaap_NondesignatedMember		 [3]
Derivatives not designated as hedging instruments | Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member]    
Assets:    
Derivative assets not designated as hedging instruments 585,474us-gaap_DerivativeFairValueOfDerivativeAsset
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel2Member
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
/ us-gaap_HedgingDesignationAxis
= us-gaap_NondesignatedMember		 [3] 592,208us-gaap_DerivativeFairValueOfDerivativeAsset
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel2Member
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
/ us-gaap_HedgingDesignationAxis
= us-gaap_NondesignatedMember		 [3]
Liabilities:    
Derivatives 398us-gaap_DerivativeFairValueOfDerivativeLiability
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel2Member
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
/ us-gaap_HedgingDesignationAxis
= us-gaap_NondesignatedMember		 [3] 70us-gaap_DerivativeFairValueOfDerivativeLiability
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel2Member
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
/ us-gaap_HedgingDesignationAxis
= us-gaap_NondesignatedMember		 [3]
Derivatives not designated as hedging instruments | Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 3 [Member]    
Assets:    
Derivative assets not designated as hedging instruments 0us-gaap_DerivativeFairValueOfDerivativeAsset
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel3Member
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
/ us-gaap_HedgingDesignationAxis
= us-gaap_NondesignatedMember		 [3] 0us-gaap_DerivativeFairValueOfDerivativeAsset
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel3Member
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
/ us-gaap_HedgingDesignationAxis
= us-gaap_NondesignatedMember		 [3]
Liabilities:    
Derivatives $ 0us-gaap_DerivativeFairValueOfDerivativeLiability
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel3Member
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
/ us-gaap_HedgingDesignationAxis
= us-gaap_NondesignatedMember		 [3] $ 0us-gaap_DerivativeFairValueOfDerivativeLiability
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel3Member
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
/ us-gaap_HedgingDesignationAxis
= us-gaap_NondesignatedMember		 [3]
[1] This represents a non-financial asset or liability that is measured at fair value on a nonrecurring basis.
[2] This represents a non-financial asset that is measured at fair value on a nonrecurring basis.
[3] This represents a financial asset or liability that is measured at fair value on a recurring basis.