v2.4.1.9

Retirement Plans (Fair Value Of Pension Plan Assets) (Details) (USD $) In Millions, unless otherwise specified | Jan. 31, 2015 | Feb. 01, 2014
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Fair value of pension investments | $ 97 us-gaap_InvestmentsFairValueDisclosure | $ 75 us-gaap_InvestmentsFairValueDisclosure
Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] |  |
Fair value of pension investments | 0 us-gaap_InvestmentsFairValueDisclosure / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member | 0 us-gaap_InvestmentsFairValueDisclosure / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member
Significant Observable Inputs (Level 2) [Member] |  |
Fair value of pension investments | 97 us-gaap_InvestmentsFairValueDisclosure / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member | 75 us-gaap_InvestmentsFairValueDisclosure / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member
Significant Unobservable Inputs (Level 3) [Member] |  |
Fair value of pension investments | 0 us-gaap_InvestmentsFairValueDisclosure / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member | 0 us-gaap_InvestmentsFairValueDisclosure / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member
Pension Plan [Member] |  |
Cash and cash equivalents | 248 us-gaap_CashAndCashEquivalentsFairValueDisclosure / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember | 211 us-gaap_CashAndCashEquivalentsFairValueDisclosure / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember
Fair value of pension investments | 3,685 us-gaap_InvestmentsFairValueDisclosure / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember | 3,580 us-gaap_InvestmentsFairValueDisclosure / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember
Pension Plan [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] |  |
Cash and cash equivalents | 0 us-gaap_CashAndCashEquivalentsFairValueDisclosure / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member | 0 us-gaap_CashAndCashEquivalentsFairValueDisclosure / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member
Fair value of pension investments | 344 us-gaap_InvestmentsFairValueDisclosure / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member | 354 us-gaap_InvestmentsFairValueDisclosure / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member
Pension Plan [Member] | Significant Observable Inputs (Level 2) [Member] |  |
Cash and cash equivalents | 248 us-gaap_CashAndCashEquivalentsFairValueDisclosure / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member | 211 us-gaap_CashAndCashEquivalentsFairValueDisclosure / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member
Fair value of pension investments | 2,741 us-gaap_InvestmentsFairValueDisclosure / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member | 2,678 us-gaap_InvestmentsFairValueDisclosure / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member
Pension Plan [Member] | Significant Unobservable Inputs (Level 3) [Member] |  |
Cash and cash equivalents | 0 us-gaap_CashAndCashEquivalentsFairValueDisclosure / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member | 0 us-gaap_CashAndCashEquivalentsFairValueDisclosure / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member
Fair value of pension investments | 600 us-gaap_InvestmentsFairValueDisclosure / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member | 548 us-gaap_InvestmentsFairValueDisclosure / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member
Pension Plan [Member] | Equity securities [Member] | UNITED STATES |  |
Fair value of pension investments | 821 us-gaap_InvestmentsFairValueDisclosure / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_EquitySecuritiesMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_StatementGeographicalAxis = country_US | 834 us-gaap_InvestmentsFairValueDisclosure / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_EquitySecuritiesMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_StatementGeographicalAxis = country_US
Pension Plan [Member] | Equity securities [Member] | International [Member] |  |
Fair value of pension investments | 659 us-gaap_InvestmentsFairValueDisclosure / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_EquitySecuritiesMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_StatementGeographicalAxis = m_InternationalMember | 748 us-gaap_InvestmentsFairValueDisclosure / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_EquitySecuritiesMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_StatementGeographicalAxis = m_InternationalMember
Pension Plan [Member] | Equity securities [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | UNITED STATES |  |
Fair value of pension investments | 344 us-gaap_InvestmentsFairValueDisclosure / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_EquitySecuritiesMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_StatementGeographicalAxis = country_US | 354 us-gaap_InvestmentsFairValueDisclosure / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_EquitySecuritiesMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_StatementGeographicalAxis = country_US
Pension Plan [Member] | Equity securities [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | International [Member] |  |
Fair value of pension investments | 0 us-gaap_InvestmentsFairValueDisclosure / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_EquitySecuritiesMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_StatementGeographicalAxis = m_InternationalMember | 0 us-gaap_InvestmentsFairValueDisclosure / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_EquitySecuritiesMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_StatementGeographicalAxis = m_InternationalMember
Pension Plan [Member] | Equity securities [Member] | Significant Observable Inputs (Level 2) [Member] | UNITED STATES |  |
Fair value of pension investments | 477 us-gaap_InvestmentsFairValueDisclosure / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_EquitySecuritiesMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_StatementGeographicalAxis = country_US | 480 us-gaap_InvestmentsFairValueDisclosure / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_EquitySecuritiesMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_StatementGeographicalAxis = country_US
Pension Plan [Member] | Equity securities [Member] | Significant Observable Inputs (Level 2) [Member] | International [Member] |  |
Fair value of pension investments | 659 us-gaap_InvestmentsFairValueDisclosure / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_EquitySecuritiesMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_StatementGeographicalAxis = m_InternationalMember | 748 us-gaap_InvestmentsFairValueDisclosure / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_EquitySecuritiesMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_StatementGeographicalAxis = m_InternationalMember
Pension Plan [Member] | Equity securities [Member] | Significant Unobservable Inputs (Level 3) [Member] | UNITED STATES |  |
Fair value of pension investments | 0 us-gaap_InvestmentsFairValueDisclosure / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_EquitySecuritiesMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member / us-gaap_StatementGeographicalAxis = country_US | 0 us-gaap_InvestmentsFairValueDisclosure / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_EquitySecuritiesMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member / us-gaap_StatementGeographicalAxis = country_US
Pension Plan [Member] | Equity securities [Member] | Significant Unobservable Inputs (Level 3) [Member] | International [Member] |  |
Fair value of pension investments | 0 us-gaap_InvestmentsFairValueDisclosure / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_EquitySecuritiesMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member / us-gaap_StatementGeographicalAxis = m_InternationalMember | 0 us-gaap_InvestmentsFairValueDisclosure / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_EquitySecuritiesMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member / us-gaap_StatementGeographicalAxis = m_InternationalMember
Pension Plan [Member] | U.S. Treasury bonds [Member] |  |
Fair value of pension investments | 272 us-gaap_InvestmentsFairValueDisclosure / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_USTreasurySecuritiesMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember | 221 us-gaap_InvestmentsFairValueDisclosure / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_USTreasurySecuritiesMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember
Pension Plan [Member] | U.S. Treasury bonds [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] |  |
Fair value of pension investments | 0 us-gaap_InvestmentsFairValueDisclosure / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_USTreasurySecuritiesMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member | 0 us-gaap_InvestmentsFairValueDisclosure / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_USTreasurySecuritiesMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member
Pension Plan [Member] | U.S. Treasury bonds [Member] | Significant Observable Inputs (Level 2) [Member] |  |
Fair value of pension investments | 272 us-gaap_InvestmentsFairValueDisclosure / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_USTreasurySecuritiesMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member | 221 us-gaap_InvestmentsFairValueDisclosure / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_USTreasurySecuritiesMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member
Pension Plan [Member] | U.S. Treasury bonds [Member] | Significant Unobservable Inputs (Level 3) [Member] |  |
Fair value of pension investments | 0 us-gaap_InvestmentsFairValueDisclosure / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_USTreasurySecuritiesMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member | 0 us-gaap_InvestmentsFairValueDisclosure / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_USTreasurySecuritiesMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member
Pension Plan [Member] | Other Government bonds [Member] |  |
Fair value of pension investments | 55 us-gaap_InvestmentsFairValueDisclosure / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_MunicipalBondsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember | 39 us-gaap_InvestmentsFairValueDisclosure / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_MunicipalBondsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember
Pension Plan [Member] | Other Government bonds [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] |  |
Fair value of pension investments | 0 us-gaap_InvestmentsFairValueDisclosure / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_MunicipalBondsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member | 0 us-gaap_InvestmentsFairValueDisclosure / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_MunicipalBondsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member
Pension Plan [Member] | Other Government bonds [Member] | Significant Observable Inputs (Level 2) [Member] |  |
Fair value of pension investments | 55 us-gaap_InvestmentsFairValueDisclosure / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_MunicipalBondsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member | 39 us-gaap_InvestmentsFairValueDisclosure / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_MunicipalBondsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member
Pension Plan [Member] | Other Government bonds [Member] | Significant Unobservable Inputs (Level 3) [Member] |  |
Fair value of pension investments | 0 us-gaap_InvestmentsFairValueDisclosure / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_MunicipalBondsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member | 0 us-gaap_InvestmentsFairValueDisclosure / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_MunicipalBondsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member
Pension Plan [Member] | Agency backed bonds [Member] |  |
Fair value of pension investments | 28 us-gaap_InvestmentsFairValueDisclosure / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_BondsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember | 22 us-gaap_InvestmentsFairValueDisclosure / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_BondsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember
Pension Plan [Member] | Agency backed bonds [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] |  |
Fair value of pension investments | 0 us-gaap_InvestmentsFairValueDisclosure / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_BondsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member | 0 us-gaap_InvestmentsFairValueDisclosure / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_BondsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member
Pension Plan [Member] | Agency backed bonds [Member] | Significant Observable Inputs (Level 2) [Member] |  |
Fair value of pension investments | 28 us-gaap_InvestmentsFairValueDisclosure / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_BondsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member | 22 us-gaap_InvestmentsFairValueDisclosure / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_BondsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member
Pension Plan [Member] | Agency backed bonds [Member] | Significant Unobservable Inputs (Level 3) [Member] |  |
Fair value of pension investments | 0 us-gaap_InvestmentsFairValueDisclosure / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_BondsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member | 0 us-gaap_InvestmentsFairValueDisclosure / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_BondsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member
Pension Plan [Member] | Corporate bonds [Member] |  |
Fair value of pension investments | 434 us-gaap_InvestmentsFairValueDisclosure / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_CorporateDebtSecuritiesMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember | 388 us-gaap_InvestmentsFairValueDisclosure / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_CorporateDebtSecuritiesMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember
Pension Plan [Member] | Corporate bonds [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] |  |
Fair value of pension investments | 0 us-gaap_InvestmentsFairValueDisclosure / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_CorporateDebtSecuritiesMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member | 0 us-gaap_InvestmentsFairValueDisclosure / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_CorporateDebtSecuritiesMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member
Pension Plan [Member] | Corporate bonds [Member] | Significant Observable Inputs (Level 2) [Member] |  |
Fair value of pension investments | 434 us-gaap_InvestmentsFairValueDisclosure / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_CorporateDebtSecuritiesMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member | 388 us-gaap_InvestmentsFairValueDisclosure / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_CorporateDebtSecuritiesMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member
Pension Plan [Member] | Corporate bonds [Member] | Significant Unobservable Inputs (Level 3) [Member] |  |
Fair value of pension investments | 0 us-gaap_InvestmentsFairValueDisclosure / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_CorporateDebtSecuritiesMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member | 0 us-gaap_InvestmentsFairValueDisclosure / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_CorporateDebtSecuritiesMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member
Pension Plan [Member] | Mortgage-backed securities and forwards [Member] |  |
Fair value of pension investments | 91 us-gaap_InvestmentsFairValueDisclosure / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_MortgageBackedSecuritiesMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember | 95 us-gaap_InvestmentsFairValueDisclosure / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_MortgageBackedSecuritiesMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember
Pension Plan [Member] | Mortgage-backed securities and forwards [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] |  |
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Pension Plan [Member] | Asset-backed securities [Member] |  |
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Pension Plan [Member] | Asset-backed securities [Member] | Significant Observable Inputs (Level 2) [Member] |  |
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Pension Plan [Member] | Pooled funds [Member] |  |
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Pension Plan [Member] | Real Estate [Member] |  |
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