XML 22 R54.htm IDEA: XBRL DOCUMENT
v2.4.1.9

Pension Benefits Fair Value of Plan Assets in Heirarchy (Details) (USD $) In Thousands, unless otherwise specified | 12 Months Ended |
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Dec. 31, 2014 | Dec. 31, 2013 | Dec. 31, 2012
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value | $ 4,864 us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue |  | $ 3,421 us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue |  | $ 2,384 us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue
Defined Benefit Plan, Fair Value of Plan Assets | 27,940 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets |  | 24,658 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets |  | 20,254 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
Defined Benefit Plan, Asset Allocation | 100.00%us-gaap_DefinedBenefitPlanWeightedAverageAssetAllocations |  | 100.00%us-gaap_DefinedBenefitPlanWeightedAverageAssetAllocations |  |
Defined Benefit Plan, Target Plan Asset Allocations | 100.00%us-gaap_DefinedBenefitPlanTargetPlanAssetAllocations |  |  |  |
Fair Value, Inputs, Level 1 [Member] |  |  |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 19,908 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member |  | 18,098 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member |  |
Fair Value, Inputs, Level 2 [Member] |  |  |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 3,168 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member |  | 3,139 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member |  |
Level 3 |  |  |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 4,864 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member |  | 3,421 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member |  |
investment Purchases [Member] |  |  |  |  |
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Transfers Into Level 3 | 1,232 us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersIntoLevel3 / us-gaap_InvestmentTypeAxis = sm_InvestmentPurchasesMember |  | 742 us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersIntoLevel3 / us-gaap_InvestmentTypeAxis = sm_InvestmentPurchasesMember |  |
Investment Income [Member] |  |  |  |  |
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Transfers Into Level 3 | 144 us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersIntoLevel3 / us-gaap_InvestmentTypeAxis = us-gaap_InvestmentIncomeMember |  | 161 us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersIntoLevel3 / us-gaap_InvestmentTypeAxis = us-gaap_InvestmentIncomeMember |  |
Unrealized Investment Gain [Member] |  |  |  |  |
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Transfers Into Level 3 | 67 us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersIntoLevel3 / us-gaap_InvestmentTypeAxis = sm_UnrealizedInvestmentGainMember |  | 134 us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersIntoLevel3 / us-gaap_InvestmentTypeAxis = sm_UnrealizedInvestmentGainMember |  |
Cash And Money Market Funds [Member] |  |  |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_InvestmentTypeAxis = sm_CashAndMoneyMarketFundsMember |  | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_InvestmentTypeAxis = sm_CashAndMoneyMarketFundsMember |  |
Defined Benefit Plan, Asset Allocation | 0.00%us-gaap_DefinedBenefitPlanWeightedAverageAssetAllocations / us-gaap_InvestmentTypeAxis = sm_CashAndMoneyMarketFundsMember |  | 0.00%us-gaap_DefinedBenefitPlanWeightedAverageAssetAllocations / us-gaap_InvestmentTypeAxis = sm_CashAndMoneyMarketFundsMember |  |
Cash And Money Market Funds [Member] | Fair Value, Inputs, Level 1 [Member] |  |  |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_InvestmentTypeAxis = sm_CashAndMoneyMarketFundsMember |  | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_InvestmentTypeAxis = sm_CashAndMoneyMarketFundsMember |  |
Cash And Money Market Funds [Member] | Fair Value, Inputs, Level 2 [Member] |  |  |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_InvestmentTypeAxis = sm_CashAndMoneyMarketFundsMember |  | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_InvestmentTypeAxis = sm_CashAndMoneyMarketFundsMember |  |
Cash And Money Market Funds [Member] | Level 3 |  |  |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member / us-gaap_InvestmentTypeAxis = sm_CashAndMoneyMarketFundsMember |  | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member / us-gaap_InvestmentTypeAxis = sm_CashAndMoneyMarketFundsMember |  |
Domestic Equity Securities [Member] |  |  |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 7,569 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_InvestmentTypeAxis = sm_DomesticEquitySecuritiesMember | [1] | 7,371 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_InvestmentTypeAxis = sm_DomesticEquitySecuritiesMember | [1] |
Defined Benefit Plan, Asset Allocation | 27.10%us-gaap_DefinedBenefitPlanWeightedAverageAssetAllocations / us-gaap_InvestmentTypeAxis = sm_DomesticEquitySecuritiesMember | [1] | 29.90%us-gaap_DefinedBenefitPlanWeightedAverageAssetAllocations / us-gaap_InvestmentTypeAxis = sm_DomesticEquitySecuritiesMember | [1] |
Domestic Equity Securities [Member] | Fair Value, Inputs, Level 1 [Member] |  |  |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 5,550 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_InvestmentTypeAxis = sm_DomesticEquitySecuritiesMember | [1] | 4,888 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_InvestmentTypeAxis = sm_DomesticEquitySecuritiesMember | [1] |
Domestic Equity Securities [Member] | Fair Value, Inputs, Level 2 [Member] |  |  |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 2,019 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_InvestmentTypeAxis = sm_DomesticEquitySecuritiesMember | [1] | 2,483 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_InvestmentTypeAxis = sm_DomesticEquitySecuritiesMember | [1] |
Domestic Equity Securities [Member] | Level 3 |  |  |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member / us-gaap_InvestmentTypeAxis = sm_DomesticEquitySecuritiesMember | [1] | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member / us-gaap_InvestmentTypeAxis = sm_DomesticEquitySecuritiesMember | [1] |
International Equity Securities [Member] |  |  |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 3,498 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_InvestmentTypeAxis = sm_InternationalEquitySecuritiesMember | [2] | 3,373 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_InvestmentTypeAxis = sm_InternationalEquitySecuritiesMember | [2] |
Defined Benefit Plan, Asset Allocation | 12.50%us-gaap_DefinedBenefitPlanWeightedAverageAssetAllocations / us-gaap_InvestmentTypeAxis = sm_InternationalEquitySecuritiesMember | [2] | 13.70%us-gaap_DefinedBenefitPlanWeightedAverageAssetAllocations / us-gaap_InvestmentTypeAxis = sm_InternationalEquitySecuritiesMember | [2] |
International Equity Securities [Member] | Fair Value, Inputs, Level 1 [Member] |  |  |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 3,498 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_InvestmentTypeAxis = sm_InternationalEquitySecuritiesMember | [2] | 3,373 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_InvestmentTypeAxis = sm_InternationalEquitySecuritiesMember | [2] |
International Equity Securities [Member] | Fair Value, Inputs, Level 2 [Member] |  |  |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_InvestmentTypeAxis = sm_InternationalEquitySecuritiesMember | [2] | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_InvestmentTypeAxis = sm_InternationalEquitySecuritiesMember | [2] |
International Equity Securities [Member] | Level 3 |  |  |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member / us-gaap_InvestmentTypeAxis = sm_InternationalEquitySecuritiesMember | [2] | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member / us-gaap_InvestmentTypeAxis = sm_InternationalEquitySecuritiesMember | [2] |
Equity Securities [Member] |  |  |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 11,067 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_InvestmentTypeAxis = us-gaap_EquitySecuritiesMember |  | 10,744 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_InvestmentTypeAxis = us-gaap_EquitySecuritiesMember |  |
Defined Benefit Plan, Asset Allocation | 39.60%us-gaap_DefinedBenefitPlanWeightedAverageAssetAllocations / us-gaap_InvestmentTypeAxis = us-gaap_EquitySecuritiesMember |  | 43.60%us-gaap_DefinedBenefitPlanWeightedAverageAssetAllocations / us-gaap_InvestmentTypeAxis = us-gaap_EquitySecuritiesMember |  |
Defined Benefit Plan, Target Plan Asset Allocations | 42.00%us-gaap_DefinedBenefitPlanTargetPlanAssetAllocations / us-gaap_InvestmentTypeAxis = us-gaap_EquitySecuritiesMember |  |  |  |
Equity Securities [Member] | Fair Value, Inputs, Level 1 [Member] |  |  |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 9,048 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_InvestmentTypeAxis = us-gaap_EquitySecuritiesMember |  | 8,261 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_InvestmentTypeAxis = us-gaap_EquitySecuritiesMember |  |
Equity Securities [Member] | Fair Value, Inputs, Level 2 [Member] |  |  |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 2,019 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_InvestmentTypeAxis = us-gaap_EquitySecuritiesMember |  | 2,483 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_InvestmentTypeAxis = us-gaap_EquitySecuritiesMember |  |
Equity Securities [Member] | Level 3 |  |  |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member / us-gaap_InvestmentTypeAxis = us-gaap_EquitySecuritiesMember |  | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member / us-gaap_InvestmentTypeAxis = us-gaap_EquitySecuritiesMember |  |
High-yield Bonds [Member] |  |  |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 797 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_InvestmentTypeAxis = sm_HighYieldBondsMember | [3] | 1,448 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_InvestmentTypeAxis = sm_HighYieldBondsMember | [3] |
Defined Benefit Plan, Asset Allocation | 2.90%us-gaap_DefinedBenefitPlanWeightedAverageAssetAllocations / us-gaap_InvestmentTypeAxis = sm_HighYieldBondsMember | [3] | 5.90%us-gaap_DefinedBenefitPlanWeightedAverageAssetAllocations / us-gaap_InvestmentTypeAxis = sm_HighYieldBondsMember | [3] |
High-yield Bonds [Member] | Fair Value, Inputs, Level 1 [Member] |  |  |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 797 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_InvestmentTypeAxis = sm_HighYieldBondsMember | [3] | 1,448 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_InvestmentTypeAxis = sm_HighYieldBondsMember | [3] |
High-yield Bonds [Member] | Fair Value, Inputs, Level 2 [Member] |  |  |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_InvestmentTypeAxis = sm_HighYieldBondsMember | [3] | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_InvestmentTypeAxis = sm_HighYieldBondsMember | [3] |
High-yield Bonds [Member] | Level 3 |  |  |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member / us-gaap_InvestmentTypeAxis = sm_HighYieldBondsMember | [3] | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member / us-gaap_InvestmentTypeAxis = sm_HighYieldBondsMember | [3] |
Fixed Income Funds [Member] |  |  |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 6,247 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_InvestmentTypeAxis = us-gaap_FixedIncomeInvestmentsMember | [4] | 5,006 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_InvestmentTypeAxis = us-gaap_FixedIncomeInvestmentsMember | [4] |
Defined Benefit Plan, Asset Allocation | 22.40%us-gaap_DefinedBenefitPlanWeightedAverageAssetAllocations / us-gaap_InvestmentTypeAxis = us-gaap_FixedIncomeInvestmentsMember | [4] | 20.30%us-gaap_DefinedBenefitPlanWeightedAverageAssetAllocations / us-gaap_InvestmentTypeAxis = us-gaap_FixedIncomeInvestmentsMember | [4] |
Fixed Income Funds [Member] | Fair Value, Inputs, Level 1 [Member] |  |  |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 6,247 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_InvestmentTypeAxis = us-gaap_FixedIncomeInvestmentsMember | [4] | 5,006 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_InvestmentTypeAxis = us-gaap_FixedIncomeInvestmentsMember | [4] |
Fixed Income Funds [Member] | Fair Value, Inputs, Level 2 [Member] |  |  |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_InvestmentTypeAxis = us-gaap_FixedIncomeInvestmentsMember | [4] | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_InvestmentTypeAxis = us-gaap_FixedIncomeInvestmentsMember | [4] |
Fixed Income Funds [Member] | Level 3 |  |  |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member / us-gaap_InvestmentTypeAxis = us-gaap_FixedIncomeInvestmentsMember | [4] | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member / us-gaap_InvestmentTypeAxis = us-gaap_FixedIncomeInvestmentsMember | [4] |
Floating Rate Corporate Debt [Member] |  |  |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 2,413 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_InvestmentTypeAxis = sm_FloatingRateCorporateDebtMember | [5] | 1,483 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_InvestmentTypeAxis = sm_FloatingRateCorporateDebtMember | [5] |
Defined Benefit Plan, Asset Allocation | 8.60%us-gaap_DefinedBenefitPlanWeightedAverageAssetAllocations / us-gaap_InvestmentTypeAxis = sm_FloatingRateCorporateDebtMember | [5] | 6.00%us-gaap_DefinedBenefitPlanWeightedAverageAssetAllocations / us-gaap_InvestmentTypeAxis = sm_FloatingRateCorporateDebtMember | [5] |
Floating Rate Corporate Debt [Member] | Fair Value, Inputs, Level 1 [Member] |  |  |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 2,413 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_InvestmentTypeAxis = sm_FloatingRateCorporateDebtMember | [5] | 1,483 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_InvestmentTypeAxis = sm_FloatingRateCorporateDebtMember | [5] |
Floating Rate Corporate Debt [Member] | Fair Value, Inputs, Level 2 [Member] |  |  |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_InvestmentTypeAxis = sm_FloatingRateCorporateDebtMember | [5] | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_InvestmentTypeAxis = sm_FloatingRateCorporateDebtMember | [5] |
Floating Rate Corporate Debt [Member] | Level 3 |  |  |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member / us-gaap_InvestmentTypeAxis = sm_FloatingRateCorporateDebtMember | [5] | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member / us-gaap_InvestmentTypeAxis = sm_FloatingRateCorporateDebtMember | [5] |
Debt Securities [Member] |  |  |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 9,457 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_InvestmentTypeAxis = us-gaap_DebtSecuritiesMember |  | 7,937 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_InvestmentTypeAxis = us-gaap_DebtSecuritiesMember |  |
Defined Benefit Plan, Asset Allocation | 33.90%us-gaap_DefinedBenefitPlanWeightedAverageAssetAllocations / us-gaap_InvestmentTypeAxis = us-gaap_DebtSecuritiesMember |  | 32.20%us-gaap_DefinedBenefitPlanWeightedAverageAssetAllocations / us-gaap_InvestmentTypeAxis = us-gaap_DebtSecuritiesMember |  |
Defined Benefit Plan, Target Plan Asset Allocations | 35.00%us-gaap_DefinedBenefitPlanTargetPlanAssetAllocations / us-gaap_InvestmentTypeAxis = us-gaap_DebtSecuritiesMember |  |  |  |
Debt Securities [Member] | Fair Value, Inputs, Level 1 [Member] |  |  |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 9,457 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_InvestmentTypeAxis = us-gaap_DebtSecuritiesMember |  | 7,937 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_InvestmentTypeAxis = us-gaap_DebtSecuritiesMember |  |
Debt Securities [Member] | Fair Value, Inputs, Level 2 [Member] |  |  |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_InvestmentTypeAxis = us-gaap_DebtSecuritiesMember |  | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_InvestmentTypeAxis = us-gaap_DebtSecuritiesMember |  |
Debt Securities [Member] | Level 3 |  |  |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member / us-gaap_InvestmentTypeAxis = us-gaap_DebtSecuritiesMember |  | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member / us-gaap_InvestmentTypeAxis = us-gaap_DebtSecuritiesMember |  |
Commodities Investment [Member] |  |  |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 810 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_InvestmentTypeAxis = us-gaap_CommoditiesInvestmentMember | [6] | 945 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_InvestmentTypeAxis = us-gaap_CommoditiesInvestmentMember | [6] |
Defined Benefit Plan, Asset Allocation | 2.90%us-gaap_DefinedBenefitPlanWeightedAverageAssetAllocations / us-gaap_InvestmentTypeAxis = us-gaap_CommoditiesInvestmentMember | [6] | 3.80%us-gaap_DefinedBenefitPlanWeightedAverageAssetAllocations / us-gaap_InvestmentTypeAxis = us-gaap_CommoditiesInvestmentMember | [6] |
Commodities Investment [Member] | Fair Value, Inputs, Level 1 [Member] |  |  |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 810 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_InvestmentTypeAxis = us-gaap_CommoditiesInvestmentMember | [6] | 945 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_InvestmentTypeAxis = us-gaap_CommoditiesInvestmentMember | [6] |
Commodities Investment [Member] | Fair Value, Inputs, Level 2 [Member] |  |  |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_InvestmentTypeAxis = us-gaap_CommoditiesInvestmentMember | [6] | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_InvestmentTypeAxis = us-gaap_CommoditiesInvestmentMember | [6] |
Commodities Investment [Member] | Level 3 |  |  |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member / us-gaap_InvestmentTypeAxis = us-gaap_CommoditiesInvestmentMember | [6] | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member / us-gaap_InvestmentTypeAxis = us-gaap_CommoditiesInvestmentMember | [6] |
Real Estate Investment [Member] |  |  |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 1,327 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_InvestmentTypeAxis = us-gaap_RealEstateInvestmentMember | [7] | 859 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_InvestmentTypeAxis = us-gaap_RealEstateInvestmentMember | [7] |
Defined Benefit Plan, Asset Allocation | 4.70%us-gaap_DefinedBenefitPlanWeightedAverageAssetAllocations / us-gaap_InvestmentTypeAxis = us-gaap_RealEstateInvestmentMember | [7] | 3.50%us-gaap_DefinedBenefitPlanWeightedAverageAssetAllocations / us-gaap_InvestmentTypeAxis = us-gaap_RealEstateInvestmentMember | [7] |
Real Estate Investment [Member] | Fair Value, Inputs, Level 1 [Member] |  |  |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_InvestmentTypeAxis = us-gaap_RealEstateInvestmentMember | [7] | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_InvestmentTypeAxis = us-gaap_RealEstateInvestmentMember | [7] |
Real Estate Investment [Member] | Fair Value, Inputs, Level 2 [Member] |  |  |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_InvestmentTypeAxis = us-gaap_RealEstateInvestmentMember | [7] | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_InvestmentTypeAxis = us-gaap_RealEstateInvestmentMember | [7] |
Real Estate Investment [Member] | Level 3 |  |  |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 1,327 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member / us-gaap_InvestmentTypeAxis = us-gaap_RealEstateInvestmentMember | [7] | 859 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member / us-gaap_InvestmentTypeAxis = us-gaap_RealEstateInvestmentMember | [7] |
Hedge Funds [Member] |  |  |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 4,130 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_InvestmentTypeAxis = us-gaap_HedgeFundsMember | [8] | 3,517 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_InvestmentTypeAxis = us-gaap_HedgeFundsMember | [8] |
Defined Benefit Plan, Asset Allocation | 14.80%us-gaap_DefinedBenefitPlanWeightedAverageAssetAllocations / us-gaap_InvestmentTypeAxis = us-gaap_HedgeFundsMember | [8] | 14.30%us-gaap_DefinedBenefitPlanWeightedAverageAssetAllocations / us-gaap_InvestmentTypeAxis = us-gaap_HedgeFundsMember | [8] |
Hedge Funds [Member] | Fair Value, Inputs, Level 1 [Member] |  |  |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 593 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_InvestmentTypeAxis = us-gaap_HedgeFundsMember | [8] | 955 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_InvestmentTypeAxis = us-gaap_HedgeFundsMember | [8] |
Hedge Funds [Member] | Fair Value, Inputs, Level 2 [Member] |  |  |  |  |
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Hedge Funds [Member] | Level 3 |  |  |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 3,537 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member / us-gaap_InvestmentTypeAxis = us-gaap_HedgeFundsMember | [8] | 2,562 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member / us-gaap_InvestmentTypeAxis = us-gaap_HedgeFundsMember | [8] |
Collective Investment Trust [Member] |  |  |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 1,149 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_InvestmentTypeAxis = sm_CollectiveInvestmentTrustMember | [9] | 656 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_InvestmentTypeAxis = sm_CollectiveInvestmentTrustMember | [9] |
Defined Benefit Plan, Asset Allocation | 4.10%us-gaap_DefinedBenefitPlanWeightedAverageAssetAllocations / us-gaap_InvestmentTypeAxis = sm_CollectiveInvestmentTrustMember | [9] | 2.60%us-gaap_DefinedBenefitPlanWeightedAverageAssetAllocations / us-gaap_InvestmentTypeAxis = sm_CollectiveInvestmentTrustMember | [9] |
Collective Investment Trust [Member] | Fair Value, Inputs, Level 1 [Member] |  |  |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_InvestmentTypeAxis = sm_CollectiveInvestmentTrustMember | [9] | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_InvestmentTypeAxis = sm_CollectiveInvestmentTrustMember | [9] |
Collective Investment Trust [Member] | Fair Value, Inputs, Level 2 [Member] |  |  |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 1,149 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_InvestmentTypeAxis = sm_CollectiveInvestmentTrustMember | [9] | 656 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_InvestmentTypeAxis = sm_CollectiveInvestmentTrustMember | [9] |
Collective Investment Trust [Member] | Level 3 |  |  |  |  |
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Other Investments [Member] |  |  |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 7,416 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_InvestmentTypeAxis = us-gaap_OtherInvestmentsMember |  | 5,977 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_InvestmentTypeAxis = us-gaap_OtherInvestmentsMember |  |
Other Investments [Member] | Fair Value, Inputs, Level 1 [Member] |  |  |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 1,403 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_InvestmentTypeAxis = us-gaap_OtherInvestmentsMember |  | 1,900 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_InvestmentTypeAxis = us-gaap_OtherInvestmentsMember |  |
Other Investments [Member] | Fair Value, Inputs, Level 2 [Member] |  |  |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 1,149 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_InvestmentTypeAxis = us-gaap_OtherInvestmentsMember |  | 656 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_InvestmentTypeAxis = us-gaap_OtherInvestmentsMember |  |
Other Investments [Member] | Level 3 |  |  |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | $ 4,864 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member / us-gaap_InvestmentTypeAxis = us-gaap_OtherInvestmentsMember |  | $ 3,421 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member / us-gaap_InvestmentTypeAxis = us-gaap_OtherInvestmentsMember |  |
Other than Securities Investment [Member] |  |  |  |  |
Defined Benefit Plan, Asset Allocation | 26.50%us-gaap_DefinedBenefitPlanWeightedAverageAssetAllocations / us-gaap_InvestmentTypeAxis = us-gaap_OtherThanSecuritiesInvestmentMember |  | 24.20%us-gaap_DefinedBenefitPlanWeightedAverageAssetAllocations / us-gaap_InvestmentTypeAxis = us-gaap_OtherThanSecuritiesInvestmentMember |  |
Defined Benefit Plan, Target Plan Asset Allocations | 23.00%us-gaap_DefinedBenefitPlanTargetPlanAssetAllocations / us-gaap_InvestmentTypeAxis = us-gaap_OtherThanSecuritiesInvestmentMember |  |  |  |
[1] | Level 1 equity securities consist of United States large and small capitalization companies, which are actively traded securities that can be sold upon demand. Level 2 equity securities are investments in a collective investment fund that is valued at net asset value based on the value of the underlying investments and total units outstanding on a daily basis. The objective of this fund is to approximate the S&P 500 by investing in one or more collective investment funds.
[2] | International equity securities consists of a well-diversified portfolio of holdings of mostly large issuers organized in developed countries with liquid markets, commingled with investments in equity securities of issuers located in emerging markets and believed to have strong sustainable financial productivity at attractive valuations.
[3] | High-yield bonds consist of non-investment grade fixed income securities. The investment objective is to obtain high current income. Due to the increased level of default risk, security selection focuses on credit-risk analysis.
[4] | The objective is to achieve value added from sector or issue selection by constructing a portfolio to approximate the investment results of the Barclay's Capital Aggregate Bond Index with a modest amount of variability in duration around the index.
[5] | Investments consist of floating rate bank loans. The interest rates on these loans are typically reset on a periodic basis to account for changes in the level of interest rates.
[6] | Investments with exposure to commodity price movements, primarily through the use of futures, swaps and other commodity-linked securities.
[7] | The investment objective of direct real estate is to provide current income with the potential for long-term capital appreciation. Ownership in real estate entails a long-term time horizon, periodic valuations, and potentially low liquidity.
[8] | The hedge fund portfolio includes an investment in an actively traded global mutual fund that focuses on alternative investments and a hedge fund of funds that invests both long and short using a variety of investment strategies.
[9] | (9)Collective investment trusts invest in short-term investments and are valued at the net asset value of the collective investment trust. The net asset value, as provided by the trustee, is used as a practical expedient to estimate fair value. The net asset value is based on the fair value of the underlying investments held by the fund less its liabilities.

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