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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 | $ 585,474 us-gaap_DerivativeFairValueOfDerivativeAsset |  | $ 592,208 us-gaap_DerivativeFairValueOfDerivativeAsset |
Proved Oil and Gas Property, Successful Effort Method | 7,006,832 us-gaap_ProvedOilAndGasPropertySuccessfulEffortMethod |  | 7,348,436 us-gaap_ProvedOilAndGasPropertySuccessfulEffortMethod |
Disposal Group, Including Discontinued Operation, Long Lived Assets, Current | 184,951 us-gaap_DisposalGroupIncludingDiscontinuedOperationLongLivedAssetsCurrent |  | 17,891 us-gaap_DisposalGroupIncludingDiscontinuedOperationLongLivedAssetsCurrent |
Liabilities: |  |  |  |
Derivatives | (398)us-gaap_DerivativeFairValueOfDerivativeLiability |  | (70)us-gaap_DerivativeFairValueOfDerivativeLiability |
Deferred Compensation Cash-based Arrangements, Liability, Classified, Noncurrent | 22,802 us-gaap_DeferredCompensationCashbasedArrangementsLiabilityClassifiedNoncurrent |  | 27,136 us-gaap_DeferredCompensationCashbasedArrangementsLiabilityClassifiedNoncurrent |
Asset Retirement Obligations, Noncurrent | 14,286 sm_AssetRetirementObligationsAssetsHeldForSaleNoncurrent |  | 438 sm_AssetRetirementObligationsAssetsHeldForSaleNoncurrent |
Fair Value, Measurements, Nonrecurring [Member] | Fair Value, Inputs, Level 1 [Member] |  |  |  |
Assets: |  |  |  |
Proved Oil and Gas Property, Successful Effort Method | 0 us-gaap_ProvedOilAndGasPropertySuccessfulEffortMethod / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsNonrecurringMember | [1] | 0 us-gaap_ProvedOilAndGasPropertySuccessfulEffortMethod / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsNonrecurringMember | [2]
Disposal Group, Including Discontinued Operation, Long Lived Assets, Current | 0 us-gaap_DisposalGroupIncludingDiscontinuedOperationLongLivedAssetsCurrent / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsNonrecurringMember | [1] | 0 us-gaap_DisposalGroupIncludingDiscontinuedOperationLongLivedAssetsCurrent / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsNonrecurringMember | [2]
Liabilities: |  |  |  |
Asset Retirement Obligations, Noncurrent | 0 sm_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 | 0 us-gaap_ProvedOilAndGasPropertySuccessfulEffortMethod / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsNonrecurringMember | [1] | 0 us-gaap_ProvedOilAndGasPropertySuccessfulEffortMethod / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsNonrecurringMember | [2]
Disposal Group, Including Discontinued Operation, Long Lived Assets, Current | 0 us-gaap_DisposalGroupIncludingDiscontinuedOperationLongLivedAssetsCurrent / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsNonrecurringMember | [1] | 0 us-gaap_DisposalGroupIncludingDiscontinuedOperationLongLivedAssetsCurrent / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsNonrecurringMember | [2]
Liabilities: |  |  |  |
Asset Retirement Obligations, Noncurrent | 0 sm_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 | 48,969 us-gaap_ProvedOilAndGasPropertySuccessfulEffortMethod / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsNonrecurringMember | [1] | 33,423 us-gaap_ProvedOilAndGasPropertySuccessfulEffortMethod / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsNonrecurringMember | [2]
Disposal Group, Including Discontinued Operation, Long Lived Assets, Current | 58,779 us-gaap_DisposalGroupIncludingDiscontinuedOperationLongLivedAssetsCurrent / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsNonrecurringMember | [1] | 17,891 us-gaap_DisposalGroupIncludingDiscontinuedOperationLongLivedAssetsCurrent / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsNonrecurringMember | [2]
Liabilities: |  |  |  |
Asset Retirement Obligations, Noncurrent | 9,509 sm_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 | 0 us-gaap_DeferredCompensationCashbasedArrangementsLiabilityClassifiedNoncurrent / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember | [3] | 0 us-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 | 0 us-gaap_DeferredCompensationCashbasedArrangementsLiabilityClassifiedNoncurrent / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember | [3] | 0 us-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 | 22,802 us-gaap_DeferredCompensationCashbasedArrangementsLiabilityClassifiedNoncurrent / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember | [3] | 27,136 us-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 | 0 us-gaap_DerivativeFairValueOfDerivativeAsset / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember / us-gaap_HedgingDesignationAxis = us-gaap_NondesignatedMember | [3] | 0 us-gaap_DerivativeFairValueOfDerivativeAsset / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember / us-gaap_HedgingDesignationAxis = us-gaap_NondesignatedMember | [3]
Liabilities: |  |  |  |
Derivatives | 0 us-gaap_DerivativeFairValueOfDerivativeLiability / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember / us-gaap_HedgingDesignationAxis = us-gaap_NondesignatedMember | [3] | 0 us-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 | 585,474 us-gaap_DerivativeFairValueOfDerivativeAsset / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember / us-gaap_HedgingDesignationAxis = us-gaap_NondesignatedMember | [3] | 592,208 us-gaap_DerivativeFairValueOfDerivativeAsset / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember / us-gaap_HedgingDesignationAxis = us-gaap_NondesignatedMember | [3]
Liabilities: |  |  |  |
Derivatives | 398 us-gaap_DerivativeFairValueOfDerivativeLiability / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember / us-gaap_HedgingDesignationAxis = us-gaap_NondesignatedMember | [3] | 70 us-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 | 0 us-gaap_DerivativeFairValueOfDerivativeAsset / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember / us-gaap_HedgingDesignationAxis = us-gaap_NondesignatedMember | [3] | 0 us-gaap_DerivativeFairValueOfDerivativeAsset / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember / us-gaap_HedgingDesignationAxis = us-gaap_NondesignatedMember | [3]
Liabilities: |  |  |  |
Derivatives | $ 0 us-gaap_DerivativeFairValueOfDerivativeLiability / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember / us-gaap_HedgingDesignationAxis = us-gaap_NondesignatedMember | [3] | $ 0 us-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.

X
- Definition Noncurrent portion of the carrying amount of a liability for an asset retirement obligation for an asset held for sale. An asset retirement obligation is a legal obligation associated with the disposal or retirement of a tangible long-lived asset that results from the acquisition, construction or development, or the normal operations of a long-lived asset, except for certain obligations of lessees. + References No definition available. + Details
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- Definition Aggregate carrying value as of the balance sheet date of the liabilities for deferred compensation arrangements payable after one year (or the normal operating cycle, if longer). Represents currently earned compensation under cash arrangements (such as a profit-sharing plan, rabbi trust, and employee contract--excluding equity-based arrangements) that is not actually paid until a later date. + References No definition available. + Details
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- Definition Fair value, before effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets elected not to be offset. Excludes assets not subject to a master netting arrangement. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 20 -Section 50 -Paragraph 3 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=34720828&loc=SL20225862-175312 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4B -Subparagraph (a),(c) -URI http://asc.fasb.org/extlink&oid=35706170&loc=SL5624163-113959 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 20 -Section 55 -Paragraph 7 -URI http://asc.fasb.org/extlink&oid=36459792&loc=SL20226000-175313 + Details
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- Definition Fair value, before effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities elected not to be offset. Excludes liabilities not subject to a master netting arrangement. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 20 -Section 50 -Paragraph 3 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=34720828&loc=SL20225862-175312 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4B -Subparagraph (a),(c) -URI http://asc.fasb.org/extlink&oid=35706170&loc=SL5624163-113959 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 20 -Section 55 -Paragraph 7 -URI http://asc.fasb.org/extlink&oid=36459792&loc=SL20226000-175313 + Details
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- Definition Amount classified as long lived assets attributable to disposal group held for sale or disposed of, expected to be disposed of within one year or the normal operating cycle, if longer. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 205 -SubTopic 20 -Section 45 -Paragraph 10 -URI http://asc.fasb.org/extlink&oid=6892542&loc=d3e1107-107759 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 205 -SubTopic 20 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6360339&loc=d3e1436-107760 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 205 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=6360339&loc=d3e1361-107760 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 360 -SubTopic 10 -Section 45 -Paragraph 9 -URI http://asc.fasb.org/extlink&oid=8077374&loc=d3e2473-110228 + Details
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- Definition Oil and Gas properties with proved reserves under the successful effort method. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 932 -SubTopic 360 -Glossary Proved Properties -URI http://asc.fasb.org/extlink&oid=6522428 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 932 -SubTopic 360 -Section 25 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=6474861&loc=d3e64746-109465 + Details
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- Details
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