XML 62 R59.htm IDEA: XBRL DOCUMENT
v2.4.1.9

Employee Benefits, Defined Benefit Plans (Details) (USD $) In Millions, unless otherwise specified | 12 Months Ended
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Dec. 31, 2014 | Dec. 31, 2013 | Dec. 31, 2012
Postretirement Medical Obligations |  |  |  |  |  |
Accrued annual VEBA contribution | $ 13.7 kalu_AccruedAnnualVebaContribution |  | $ 16.0 kalu_AccruedAnnualVebaContribution |  |  |
Benefit Obligations and Funded Status Additional Disclosure |  |  |  |  |  |
Net asset In respect of VEBAs | 340.1 kalu_NetAssetInRespectOfVebas |  | 406.0 kalu_NetAssetInRespectOfVebas |  |  |
Net liability of VEBA | 17.2 kalu_NetLiabilityInRespectOfVeba |  | 0 kalu_NetLiabilityInRespectOfVeba |  |  |
Estimated future benefit payments |  |  |  |  |  |
Expected future benefit payments, 2015 | 30.6 us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsNextTwelveMonths |  |  |  |  |
Expected future benefit payments, 2016 | 30.4 us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearTwo |  |  |  |  |
Expected future benefit payments, 2017 | 30.2 us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearThree |  |  |  |  |
Expected future benefit payments, 2018 | 29.8 us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearFour |  |  |  |  |
Expected future benefit payments, 2019 | 29.5 us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearFive |  |  |  |  |
Expected future benefit payments, 2020-2023 | 139.5 us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsFiveFiscalYearsThereafter |  |  |  |  |
Components of Net Periodic Benefit Cost (Income) |  |  |  |  |  |
Net periodic benefit cost (income) | (23.5)us-gaap_DefinedBenefitPlanNetPeriodicBenefitCost |  | (22.0)us-gaap_DefinedBenefitPlanNetPeriodicBenefitCost |  | (11.5)us-gaap_DefinedBenefitPlanNetPeriodicBenefitCost |
Canadian pension plan |  |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |  |
Defined Benefit Plan, Accumulated Benefit Obligation | 6.2 us-gaap_DefinedBenefitPlanAccumulatedBenefitObligation / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_ForeignPensionPlansDefinedBenefitMember |  | 5.8 us-gaap_DefinedBenefitPlanAccumulatedBenefitObligation / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_ForeignPensionPlansDefinedBenefitMember |  |  |
Assumptions used to determine benefit obligations |  |  |  |  |  |
Discount rate | 4.00%us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingBenefitObligationDiscountRate / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_ForeignPensionPlansDefinedBenefitMember |  | 4.90%us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingBenefitObligationDiscountRate / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_ForeignPensionPlansDefinedBenefitMember |  |  |
Rate of compensation increase | 3.00%us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingBenefitObligationRateOfCompensationIncrease / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_ForeignPensionPlansDefinedBenefitMember |  | 3.00%us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingBenefitObligationRateOfCompensationIncrease / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_ForeignPensionPlansDefinedBenefitMember |  |  |
Assumptions used to determine net periodic benefit cost (income) |  |  |  |  |  |
Discount rate | 4.90%us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostDiscountRate / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_ForeignPensionPlansDefinedBenefitMember |  | 4.40%us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostDiscountRate / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_ForeignPensionPlansDefinedBenefitMember |  | 5.60%us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostDiscountRate / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_ForeignPensionPlansDefinedBenefitMember |
Expected long-term return on plan assets | 4.75%us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostExpectedLongTermReturnOnAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_ForeignPensionPlansDefinedBenefitMember |  | 4.50%us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostExpectedLongTermReturnOnAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_ForeignPensionPlansDefinedBenefitMember |  | 4.60%us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostExpectedLongTermReturnOnAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_ForeignPensionPlansDefinedBenefitMember |
Rate of compensation increase | 3.00%us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostRateOfCompensationIncrease / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_ForeignPensionPlansDefinedBenefitMember |  | 3.00%us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostRateOfCompensationIncrease / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_ForeignPensionPlansDefinedBenefitMember |  | 3.00%us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostRateOfCompensationIncrease / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_ForeignPensionPlansDefinedBenefitMember |
Change in benefit obligation: |  |  |  |  |  |
Obligation at beginning of year | 6.6 us-gaap_DefinedBenefitPlanBenefitObligation / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_ForeignPensionPlansDefinedBenefitMember |  | 7.0 us-gaap_DefinedBenefitPlanBenefitObligation / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_ForeignPensionPlansDefinedBenefitMember |  |  |
Foreign currency translation adjustment | (0.5)us-gaap_DefinedBenefitPlanForeignCurrencyExchangeRateChangesBenefitObligation / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_ForeignPensionPlansDefinedBenefitMember |  | (0.5)us-gaap_DefinedBenefitPlanForeignCurrencyExchangeRateChangesBenefitObligation / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_ForeignPensionPlansDefinedBenefitMember |  |  |
Service cost | 0.2 us-gaap_DefinedBenefitPlanServiceCost / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_ForeignPensionPlansDefinedBenefitMember |  | 0.3 us-gaap_DefinedBenefitPlanServiceCost / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_ForeignPensionPlansDefinedBenefitMember |  | 0.2 us-gaap_DefinedBenefitPlanServiceCost / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_ForeignPensionPlansDefinedBenefitMember |
Interest cost | 0.3 us-gaap_DefinedBenefitPlanInterestCost / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_ForeignPensionPlansDefinedBenefitMember |  | 0.3 us-gaap_DefinedBenefitPlanInterestCost / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_ForeignPensionPlansDefinedBenefitMember |  | 0.3 us-gaap_DefinedBenefitPlanInterestCost / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_ForeignPensionPlansDefinedBenefitMember |
Actuarial (gain) loss | 0.7 us-gaap_DefinedBenefitPlanActuarialGainLoss / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_ForeignPensionPlansDefinedBenefitMember |  | (0.2)us-gaap_DefinedBenefitPlanActuarialGainLoss / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_ForeignPensionPlansDefinedBenefitMember |  |  |
Plan participant contributions | 0 us-gaap_DefinedBenefitPlanContributionsByPlanParticipants / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_ForeignPensionPlansDefinedBenefitMember |  | 0 us-gaap_DefinedBenefitPlanContributionsByPlanParticipants / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_ForeignPensionPlansDefinedBenefitMember |  |  |
Benefits paid by Company | (0.3)us-gaap_DefinedBenefitPlanBenefitsPaid / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_ForeignPensionPlansDefinedBenefitMember |  | (0.3)us-gaap_DefinedBenefitPlanBenefitsPaid / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_ForeignPensionPlansDefinedBenefitMember |  |  |
Obligation at end of year | 7.0 us-gaap_DefinedBenefitPlanBenefitObligation / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_ForeignPensionPlansDefinedBenefitMember |  | 6.6 us-gaap_DefinedBenefitPlanBenefitObligation / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_ForeignPensionPlansDefinedBenefitMember |  | 7.0 us-gaap_DefinedBenefitPlanBenefitObligation / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_ForeignPensionPlansDefinedBenefitMember |
Change in plan assets: |  |  |  |  |  |
Fair market value of plan assets at beginning of year | 6.2 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_ForeignPensionPlansDefinedBenefitMember |  | 5.7 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_ForeignPensionPlansDefinedBenefitMember |  |  |
Foreign currency translation adjustment | (0.5)us-gaap_DefinedBenefitPlanForeignCurrencyExchangeRateChangesPlanAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_ForeignPensionPlansDefinedBenefitMember |  | (0.4)us-gaap_DefinedBenefitPlanForeignCurrencyExchangeRateChangesPlanAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_ForeignPensionPlansDefinedBenefitMember |  |  |
Actual return on assets | 0.6 us-gaap_DefinedBenefitPlanActualReturnOnPlanAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_ForeignPensionPlansDefinedBenefitMember |  | 0.7 us-gaap_DefinedBenefitPlanActualReturnOnPlanAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_ForeignPensionPlansDefinedBenefitMember |  |  |
Plan participant contributions | 0 us-gaap_DefinedBenefitPlanContributionsByPlanParticipants / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_ForeignPensionPlansDefinedBenefitMember |  | 0 us-gaap_DefinedBenefitPlanContributionsByPlanParticipants / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_ForeignPensionPlansDefinedBenefitMember |  |  |
Employer/Company contributions | 0.3 us-gaap_DefinedBenefitPlanContributionsByEmployer / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_ForeignPensionPlansDefinedBenefitMember |  | 0.5 us-gaap_DefinedBenefitPlanContributionsByEmployer / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_ForeignPensionPlansDefinedBenefitMember |  |  |
Benefits paid by Company | (0.3)us-gaap_DefinedBenefitPlanBenefitsPaid / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_ForeignPensionPlansDefinedBenefitMember |  | (0.3)us-gaap_DefinedBenefitPlanBenefitsPaid / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_ForeignPensionPlansDefinedBenefitMember |  |  |
Fair market value of plan assets at end of year | 6.3 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_ForeignPensionPlansDefinedBenefitMember |  | 6.2 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_ForeignPensionPlansDefinedBenefitMember |  | 5.7 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_ForeignPensionPlansDefinedBenefitMember |
Net funded status | (0.7)us-gaap_DefinedBenefitPlanFundedStatusOfPlan / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_ForeignPensionPlansDefinedBenefitMember |  | (0.4)us-gaap_DefinedBenefitPlanFundedStatusOfPlan / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_ForeignPensionPlansDefinedBenefitMember |  |  |
Net Funded Status |  |  |  |  |  |
Accumulated plan benefit obligation | (7.0)us-gaap_DefinedBenefitPlanBenefitObligation / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_ForeignPensionPlansDefinedBenefitMember |  | (6.6)us-gaap_DefinedBenefitPlanBenefitObligation / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_ForeignPensionPlansDefinedBenefitMember |  | (7.0)us-gaap_DefinedBenefitPlanBenefitObligation / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_ForeignPensionPlansDefinedBenefitMember |
Plan assets | 6.3 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_ForeignPensionPlansDefinedBenefitMember |  | 6.2 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_ForeignPensionPlansDefinedBenefitMember |  | 5.7 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_ForeignPensionPlansDefinedBenefitMember |
Net funded status | (0.7)us-gaap_DefinedBenefitPlanFundedStatusOfPlan / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_ForeignPensionPlansDefinedBenefitMember |  | (0.4)us-gaap_DefinedBenefitPlanFundedStatusOfPlan / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_ForeignPensionPlansDefinedBenefitMember |  |  |
Net benefits expected to be contributed in 2014 | 0.3 us-gaap_DefinedBenefitPlansEstimatedFutureEmployerContributionsInNextFiscalYear / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_ForeignPensionPlansDefinedBenefitMember |  |  |  |  |
Estimated future benefit payments |  |  |  |  |  |
Expected future benefit payments, 2015 | 0.3 us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsNextTwelveMonths / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_ForeignPensionPlansDefinedBenefitMember |  |  |  |  |
Expected future benefit payments, 2016 | 0.3 us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearTwo / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_ForeignPensionPlansDefinedBenefitMember |  |  |  |  |
Expected future benefit payments, 2017 | 0.3 us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearThree / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_ForeignPensionPlansDefinedBenefitMember |  |  |  |  |
Expected future benefit payments, 2018 | 0.3 us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearFour / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_ForeignPensionPlansDefinedBenefitMember |  |  |  |  |
Expected future benefit payments, 2019 | 0.3 us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearFive / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_ForeignPensionPlansDefinedBenefitMember |  |  |  |  |
Expected future benefit payments, 2020-2023 | 1.6 us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsFiveFiscalYearsThereafter / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_ForeignPensionPlansDefinedBenefitMember |  |  |  |  |
Accumulated other comprehensive (loss) income |  |  |  |  |  |
Accumulated net actuarial (losses) gains | (1.9)us-gaap_DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeNetGainsLossesBeforeTax / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_ForeignPensionPlansDefinedBenefitMember |  | (1.8)us-gaap_DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeNetGainsLossesBeforeTax / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_ForeignPensionPlansDefinedBenefitMember |  |  |
Transition assets | 0.2 us-gaap_DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeNetTransitionAssetsObligationsBeforeTax / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_ForeignPensionPlansDefinedBenefitMember |  | 0.2 us-gaap_DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeNetTransitionAssetsObligationsBeforeTax / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_ForeignPensionPlansDefinedBenefitMember |  |  |
Loss recognized in Accumulated other comprehensive income (loss) | (1.7)us-gaap_DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeBeforeTax / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_ForeignPensionPlansDefinedBenefitMember |  | (1.6)us-gaap_DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeBeforeTax / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_ForeignPensionPlansDefinedBenefitMember |  |  |
Amounts in Accumulated other comprehensive (loss) income expected to be recognized in 2014 |  |  |  |  |  |
Future amortization of prior service cost | 0.1 us-gaap_DefinedBenefitPlanFutureAmortizationOfPriorServiceCostCredit / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_ForeignPensionPlansDefinedBenefitMember |  |  |  |  |
Components of Net Periodic Benefit Cost (Income) |  |  |  |  |  |
Service cost | 0.2 us-gaap_DefinedBenefitPlanServiceCost / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_ForeignPensionPlansDefinedBenefitMember |  | 0.3 us-gaap_DefinedBenefitPlanServiceCost / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_ForeignPensionPlansDefinedBenefitMember |  | 0.2 us-gaap_DefinedBenefitPlanServiceCost / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_ForeignPensionPlansDefinedBenefitMember |
Interest cost | 0.3 us-gaap_DefinedBenefitPlanInterestCost / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_ForeignPensionPlansDefinedBenefitMember |  | 0.3 us-gaap_DefinedBenefitPlanInterestCost / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_ForeignPensionPlansDefinedBenefitMember |  | 0.3 us-gaap_DefinedBenefitPlanInterestCost / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_ForeignPensionPlansDefinedBenefitMember |
Expected return on plan assets | (0.3)us-gaap_DefinedBenefitPlanExpectedReturnOnPlanAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_ForeignPensionPlansDefinedBenefitMember |  | (0.3)us-gaap_DefinedBenefitPlanExpectedReturnOnPlanAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_ForeignPensionPlansDefinedBenefitMember |  | (0.2)us-gaap_DefinedBenefitPlanExpectedReturnOnPlanAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_ForeignPensionPlansDefinedBenefitMember |
Amortization of prior service cost | 0 us-gaap_DefinedBenefitPlanAmortizationOfPriorServiceCostCredit / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_ForeignPensionPlansDefinedBenefitMember |  | 0 us-gaap_DefinedBenefitPlanAmortizationOfPriorServiceCostCredit / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_ForeignPensionPlansDefinedBenefitMember |  | 0 us-gaap_DefinedBenefitPlanAmortizationOfPriorServiceCostCredit / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_ForeignPensionPlansDefinedBenefitMember |
Amortization of net actuarial loss (gain) | 0.1 us-gaap_DefinedBenefitPlanAmortizationOfGainsLosses / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_ForeignPensionPlansDefinedBenefitMember |  | 0.2 us-gaap_DefinedBenefitPlanAmortizationOfGainsLosses / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_ForeignPensionPlansDefinedBenefitMember |  | 0.1 us-gaap_DefinedBenefitPlanAmortizationOfGainsLosses / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_ForeignPensionPlansDefinedBenefitMember |
Canadian pension plan | London, Ontario Facility | Equity Securities |  |  |  |  |  |
Defined Benefit Plan at the London, Ontario Facility, Information About Plan Assets |  |  |  |  |  |
Actual plan asset allocations | 66.00%us-gaap_DefinedBenefitPlanWeightedAverageAssetAllocations / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_EquitySecuritiesMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_ForeignPensionPlansDefinedBenefitMember / kalu_ProductionFacilitiesAxis = kalu_LondonOntarioFacilityMember |  |  |  |  |
Asset mix target allocation on long-term investments | 66.00%us-gaap_DefinedBenefitPlanTargetPlanAssetAllocations / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_EquitySecuritiesMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_ForeignPensionPlansDefinedBenefitMember / kalu_ProductionFacilitiesAxis = kalu_LondonOntarioFacilityMember |  |  |  |  |
Canadian pension plan | London, Ontario Facility | Fixed Income Securities |  |  |  |  |  |
Defined Benefit Plan at the London, Ontario Facility, Information About Plan Assets |  |  |  |  |  |
Actual plan asset allocations | 31.00%us-gaap_DefinedBenefitPlanWeightedAverageAssetAllocations / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_FixedIncomeSecuritiesMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_ForeignPensionPlansDefinedBenefitMember / kalu_ProductionFacilitiesAxis = kalu_LondonOntarioFacilityMember |  |  |  |  |
Asset mix target allocation on long-term investments | 30.00%us-gaap_DefinedBenefitPlanTargetPlanAssetAllocations / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_FixedIncomeSecuritiesMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_ForeignPensionPlansDefinedBenefitMember / kalu_ProductionFacilitiesAxis = kalu_LondonOntarioFacilityMember |  |  |  |  |
VEBAs |  |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |  |
Defined Benefit Plan, Plan Amendments | 90.4 us-gaap_DefinedBenefitPlanPlanAmendments / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_VebasMember |  | 84.6 us-gaap_DefinedBenefitPlanPlanAmendments / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_VebasMember | [1] |  |
Postretirement Medical Obligations |  |  |  |  |  |
Cash flow in determining VEBA obligation | 20.0 kalu_CashFlowInDetermingVebaObligation / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_VebasMember |  |  |  |  |
Change in benefit obligation: |  |  |  |  |  |
Obligation at beginning of year | 374.7 us-gaap_DefinedBenefitPlanBenefitObligation / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_VebasMember | [1] | 384.1 us-gaap_DefinedBenefitPlanBenefitObligation / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_VebasMember | [1] |  |
Foreign currency translation adjustment | 0 us-gaap_DefinedBenefitPlanForeignCurrencyExchangeRateChangesBenefitObligation / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_VebasMember |  | 0 us-gaap_DefinedBenefitPlanForeignCurrencyExchangeRateChangesBenefitObligation / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_VebasMember | [1] |  |
Service cost | 2.2 us-gaap_DefinedBenefitPlanServiceCost / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_VebasMember |  | 2.5 us-gaap_DefinedBenefitPlanServiceCost / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_VebasMember | [1] | 3.4 us-gaap_DefinedBenefitPlanServiceCost / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_VebasMember |
Interest cost | 16.7 us-gaap_DefinedBenefitPlanInterestCost / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_VebasMember |  | 14.6 us-gaap_DefinedBenefitPlanInterestCost / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_VebasMember | [1] | 17.9 us-gaap_DefinedBenefitPlanInterestCost / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_VebasMember |
Actuarial (gain) loss | 10.2 us-gaap_DefinedBenefitPlanActuarialGainLoss / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_VebasMember | [2] | (91.9)us-gaap_DefinedBenefitPlanActuarialGainLoss / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_VebasMember | [1],[2] |  |
Plan participant contributions | 0 us-gaap_DefinedBenefitPlanContributionsByPlanParticipants / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_VebasMember |  | 0 us-gaap_DefinedBenefitPlanContributionsByPlanParticipants / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_VebasMember | [1] |  |
Benefits paid by VEBAs | (24.7)kalu_BenefitsPaidByVeba / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_VebasMember |  | (21.5)kalu_BenefitsPaidByVeba / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_VebasMember | [1] |  |
Reimbursement from Retiree Drug Subsidy | 1.4 us-gaap_DefinedBenefitPlanGrossPrescriptionDrugSubsidyReceiptsReceived / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_VebasMember | [3] | 2.3 us-gaap_DefinedBenefitPlanGrossPrescriptionDrugSubsidyReceiptsReceived / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_VebasMember | [1],[3] |  |
Obligation at end of year | 470.9 us-gaap_DefinedBenefitPlanBenefitObligation / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_VebasMember |  | 374.7 us-gaap_DefinedBenefitPlanBenefitObligation / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_VebasMember | [1] | 384.1 us-gaap_DefinedBenefitPlanBenefitObligation / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_VebasMember | [1]
Change in plan assets: |  |  |  |  |  |
Fair market value of plan assets at beginning of year | 780.7 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_VebasMember | [1] | 744.7 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_VebasMember | [1] |  |
Foreign currency translation adjustment | 0 us-gaap_DefinedBenefitPlanForeignCurrencyExchangeRateChangesPlanAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_VebasMember |  | 0 us-gaap_DefinedBenefitPlanForeignCurrencyExchangeRateChangesPlanAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_VebasMember | [1] |  |
Actual return on assets | 22.7 us-gaap_DefinedBenefitPlanActualReturnOnPlanAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_VebasMember |  | 39.2 us-gaap_DefinedBenefitPlanActualReturnOnPlanAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_VebasMember | [1] |  |
Plan participant contributions | 0 us-gaap_DefinedBenefitPlanContributionsByPlanParticipants / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_VebasMember |  | 0 us-gaap_DefinedBenefitPlanContributionsByPlanParticipants / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_VebasMember | [1] |  |
Employer/Company contributions | 13.7 us-gaap_DefinedBenefitPlanContributionsByEmployer / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_VebasMember | [4] | 16.0 us-gaap_DefinedBenefitPlanContributionsByEmployer / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_VebasMember | [1],[4] |  |
Benefits paid by VEBAs | (24.7)kalu_BenefitsPaidByVeba / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_VebasMember |  | (21.5)kalu_BenefitsPaidByVeba / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_VebasMember | [1] |  |
Reimbursement from Retiree Drug Subsidy | 1.4 us-gaap_DefinedBenefitPlanGrossPrescriptionDrugSubsidyReceiptsReceived / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_VebasMember | [3] | 2.3 us-gaap_DefinedBenefitPlanGrossPrescriptionDrugSubsidyReceiptsReceived / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_VebasMember | [1],[3] |  |
Fair market value of plan assets at end of year | 793.8 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_VebasMember |  | 780.7 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_VebasMember | [1] | 744.7 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_VebasMember | [1]
Net funded status | 322.9 us-gaap_DefinedBenefitPlanFundedStatusOfPlan / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_VebasMember | [5] | 406.0 us-gaap_DefinedBenefitPlanFundedStatusOfPlan / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_VebasMember | [1],[5] |  |
Benefit Obligations and Funded Status Additional Disclosure |  |  |  |  |  |
Actuarial gain due to a decrease in discount rate | (45.0)kalu_ActuarialGainLossDueToChangeInDiscountRate / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_VebasMember |  | (30.5)kalu_ActuarialGainLossDueToChangeInDiscountRate / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_VebasMember |  |  |
Actuarial gain due to higher than expected mortality rate | (37.2)kalu_ActuarialGainLossDueToChangesInCensusData / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_VebasMember |  |  |  |  |
Actuarial loss resulting from an increase in existing benefits reimbursement rates |  |  | 20.8 kalu_PriorServiceCostresultingfromachangeinbenefitcostforplanparticipants / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_VebasMember |  |  |
Actuarial (gain) loss due to projected lower benefit utilization | 53.6 kalu_Actuarialgainlossduetoprojectedlowerbenefitutilization / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_VebasMember |  |  |  |  |
Net Funded Status |  |  |  |  |  |
Accumulated plan benefit obligation | (470.9)us-gaap_DefinedBenefitPlanBenefitObligation / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_VebasMember |  | (374.7)us-gaap_DefinedBenefitPlanBenefitObligation / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_VebasMember | [1] | (384.1)us-gaap_DefinedBenefitPlanBenefitObligation / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_VebasMember | [1]
Plan assets | 793.8 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_VebasMember |  | 780.7 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_VebasMember | [1] | 744.7 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_VebasMember | [1]
Net funded status | 322.9 us-gaap_DefinedBenefitPlanFundedStatusOfPlan / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_VebasMember | [5] | 406.0 us-gaap_DefinedBenefitPlanFundedStatusOfPlan / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_VebasMember | [1],[5] |  |
Estimated future benefit payments |  |  |  |  |  |
Expected future benefit payments, 2015 | 30.3 us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsNextTwelveMonths / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_VebasMember | [6] |  |  |  |
Expected future benefit payments, 2016 | 30.1 us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearTwo / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_VebasMember | [6] |  |  |  |
Expected future benefit payments, 2017 | 29.9 us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearThree / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_VebasMember | [6] |  |  |  |
Expected future benefit payments, 2018 | 29.5 us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearFour / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_VebasMember | [6] |  |  |  |
Expected future benefit payments, 2019 | 29.2 us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearFive / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_VebasMember | [6] |  |  |  |
Expected future benefit payments, 2020-2023 | 137.9 us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsFiveFiscalYearsThereafter / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_VebasMember | [6] |  |  |  |
Accumulated other comprehensive (loss) income |  |  |  |  |  |
Accumulated net actuarial (losses) gains | 43.6 us-gaap_DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeNetGainsLossesBeforeTax / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_VebasMember |  | 84.3 us-gaap_DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeNetGainsLossesBeforeTax / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_VebasMember |  |  |
Prior service cost | (197.4)us-gaap_DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeNetPriorServiceCostCreditBeforeTax / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_VebasMember |  | (117.5)us-gaap_DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeNetPriorServiceCostCreditBeforeTax / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_VebasMember |  |  |
Loss recognized in Accumulated other comprehensive income (loss) | (153.8)us-gaap_DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeBeforeTax / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_VebasMember |  | (33.2)us-gaap_DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeBeforeTax / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_VebasMember |  |  |
Amounts in Accumulated other comprehensive (loss) income expected to be recognized in 2014 |  |  |  |  |  |
Amounts in Accumulated other comprehensive (loss) income expected to be recognized in 2014 | 18.3 us-gaap_DefinedBenefitPlanAmountToBeAmortizedFromAccumulatedOtherComprehensiveIncomeLossNextFiscalYear / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_VebasMember |  |  |  |  |
Future amortization of prior service cost | 17.3 us-gaap_DefinedBenefitPlanFutureAmortizationOfPriorServiceCostCredit / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_VebasMember |  |  |  |  |
Future amortization of actuarial gain (loss) | 1.0 us-gaap_DefinedBenefitPlanFutureAmortizationOfGainLoss / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_VebasMember |  |  |  |  |
Components of Net Periodic Benefit Cost (Income) |  |  |  |  |  |
Service cost | 2.2 us-gaap_DefinedBenefitPlanServiceCost / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_VebasMember |  | 2.5 us-gaap_DefinedBenefitPlanServiceCost / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_VebasMember | [1] | 3.4 us-gaap_DefinedBenefitPlanServiceCost / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_VebasMember |
Interest cost | 16.7 us-gaap_DefinedBenefitPlanInterestCost / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_VebasMember |  | 14.6 us-gaap_DefinedBenefitPlanInterestCost / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_VebasMember | [1] | 17.9 us-gaap_DefinedBenefitPlanInterestCost / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_VebasMember |
Expected return on plan assets | (51.4)us-gaap_DefinedBenefitPlanExpectedReturnOnPlanAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_VebasMember |  | (45.1)us-gaap_DefinedBenefitPlanExpectedReturnOnPlanAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_VebasMember |  | (40.4)us-gaap_DefinedBenefitPlanExpectedReturnOnPlanAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_VebasMember |
Amortization of prior service cost | 10.6 us-gaap_DefinedBenefitPlanAmortizationOfPriorServiceCostCredit / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_VebasMember | [7] | 4.2 us-gaap_DefinedBenefitPlanAmortizationOfPriorServiceCostCredit / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_VebasMember | [7] | 4.2 us-gaap_DefinedBenefitPlanAmortizationOfPriorServiceCostCredit / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_VebasMember | [7]
Amortization of net actuarial loss (gain) | (1.8)us-gaap_DefinedBenefitPlanAmortizationOfGainsLosses / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_VebasMember |  | 1.3 us-gaap_DefinedBenefitPlanAmortizationOfGainsLosses / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_VebasMember |  | 3.0 us-gaap_DefinedBenefitPlanAmortizationOfGainsLosses / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_VebasMember |
VEBAs | Maximum |  |  |  |  |  |
Postretirement Medical Obligations |  |  |  |  |  |
Variable cash contribution obligation to VEBAs | 20.0 kalu_PostretirementMedicalPlanContributionObligation / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_VebasMember / us-gaap_RangeAxis = us-gaap_MaximumMember |  |  |  |  |
VEBAs | Annual Cash Flows up to $20 Million |  |  |  |  |  |
Postretirement Medical Obligations |  |  |  |  |  |
Postretirement medical plan contribution obligation percentage | 10.00%kalu_PostretirementMedicalPlanContributionObligationPercentage / kalu_ContributionPercentageDeterminationAxis = kalu_AnnualCashFlowsUpToTwentyMillionDollarsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_VebasMember |  |  |  |  |
VEBAs | Annual Cash Flows in Excess of $20 Million |  |  |  |  |  |
Postretirement Medical Obligations |  |  |  |  |  |
Postretirement medical plan contribution obligation percentage | 20.00%kalu_PostretirementMedicalPlanContributionObligationPercentage / kalu_ContributionPercentageDeterminationAxis = kalu_AnnualCashFlowsInExcessOfTwentyMillionDollarsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_VebasMember |  |  |  |  |
Union VEBA |  |  |  |  |  |
Postretirement Medical Obligations |  |  |  |  |  |
Number of trustees | 4 kalu_NumberOfTrustees / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_UnionVebaMember |  |  |  |  |
Percent allocation of total contribution between VEBAs | 85.50%kalu_PercentAllocationOfTotalContributionBetweenVebas / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_UnionVebaMember |  |  |  |  |
Accrued annual VEBA contribution | 11.7 kalu_AccruedAnnualVebaContribution / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_UnionVebaMember |  |  |  |  |
Assumptions used to determine benefit obligations |  |  |  |  |  |
Discount rate | 3.80%us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingBenefitObligationDiscountRate / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_UnionVebaMember |  | 4.70%us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingBenefitObligationDiscountRate / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_UnionVebaMember |  |  |
Initial medical trend rate | 7.00%us-gaap_DefinedBenefitPlanHealthCareCostTrendRateAssumedForNextFiscalYear / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_UnionVebaMember | [8] | 7.50%us-gaap_DefinedBenefitPlanHealthCareCostTrendRateAssumedForNextFiscalYear / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_UnionVebaMember | [8] |  |
Ultimate medical trend rate | 5.00%us-gaap_DefinedBenefitPlanUltimateHealthCareCostTrendRate / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_UnionVebaMember | [8],[9] | 5.00%us-gaap_DefinedBenefitPlanUltimateHealthCareCostTrendRate / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_UnionVebaMember | [8],[9] | 5.00%us-gaap_DefinedBenefitPlanUltimateHealthCareCostTrendRate / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_UnionVebaMember | [9]
Year that rate reaches ultimate trend rate | 2019 |  | 2019 |  | 2019 |
Effect of one-percentage-point increase in medical trend rate on accumulated postretirement benefit obligation | 37.7 us-gaap_DefinedBenefitPlanEffectOfOnePercentagePointIncreaseOnAccumulatedPostretirementBenefitObligation / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_UnionVebaMember |  | 27.8 us-gaap_DefinedBenefitPlanEffectOfOnePercentagePointIncreaseOnAccumulatedPostretirementBenefitObligation / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_UnionVebaMember |  |  |
Effect of one-percentage-point decrease in medical trend rate on accumulated postretirement benefit obligation | 29.9 us-gaap_DefinedBenefitPlanEffectOfOnePercentagePointDecreaseOnAccumulatedPostretirementBenefitObligation1 / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_UnionVebaMember |  | 22.7 us-gaap_DefinedBenefitPlanEffectOfOnePercentagePointDecreaseOnAccumulatedPostretirementBenefitObligation1 / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_UnionVebaMember |  |  |
Assumptions used to determine net periodic benefit cost (income) |  |  |  |  |  |
Discount rate | 4.70%us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostDiscountRate / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_UnionVebaMember |  | 4.00%us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostDiscountRate / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_UnionVebaMember |  | 4.20%us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostDiscountRate / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_UnionVebaMember |
Expected long-term return on plan assets | 6.75%us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostExpectedLongTermReturnOnAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_UnionVebaMember | [10] | 6.25%us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostExpectedLongTermReturnOnAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_UnionVebaMember | [10] | 7.25%us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostExpectedLongTermReturnOnAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_UnionVebaMember | [10]
Initial medical trend rate | 7.50%kalu_InitialMedicalTrendRateUsedInCalculatingNetPeriodicBenefitCost / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_UnionVebaMember | [9] | 8.00%kalu_InitialMedicalTrendRateUsedInCalculatingNetPeriodicBenefitCost / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_UnionVebaMember | [9] | 8.50%kalu_InitialMedicalTrendRateUsedInCalculatingNetPeriodicBenefitCost / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_UnionVebaMember | [9]
Ultimate medical trend rate | 5.00%us-gaap_DefinedBenefitPlanUltimateHealthCareCostTrendRate / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_UnionVebaMember | [8],[9] | 5.00%us-gaap_DefinedBenefitPlanUltimateHealthCareCostTrendRate / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_UnionVebaMember | [8],[9] | 5.00%us-gaap_DefinedBenefitPlanUltimateHealthCareCostTrendRate / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_UnionVebaMember | [9]
Year that rate reaches ultimate trend rate | 2019 |  | 2019 |  | 2019 |
Effect of one-percentage-point increase on service and interest cost components | 2.6 us-gaap_DefinedBenefitPlanEffectOfOnePercentagePointIncreaseOnServiceAndInterestCostComponents / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_UnionVebaMember |  | 2.0 us-gaap_DefinedBenefitPlanEffectOfOnePercentagePointIncreaseOnServiceAndInterestCostComponents / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_UnionVebaMember |  | 2.5 us-gaap_DefinedBenefitPlanEffectOfOnePercentagePointIncreaseOnServiceAndInterestCostComponents / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_UnionVebaMember |
Effect of one-percentage-point decrease on service and interest cost components | 2.0 us-gaap_DefinedBenefitPlanEffectOfOnePercentagePointDecreaseOnServiceAndInterestCostComponents1 / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_UnionVebaMember |  | 1.5 us-gaap_DefinedBenefitPlanEffectOfOnePercentagePointDecreaseOnServiceAndInterestCostComponents1 / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_UnionVebaMember |  | 2.0 us-gaap_DefinedBenefitPlanEffectOfOnePercentagePointDecreaseOnServiceAndInterestCostComponents1 / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_UnionVebaMember |
Change in benefit obligation: |  |  |  |  |  |
Obligation at beginning of year | 312.7 us-gaap_DefinedBenefitPlanBenefitObligation / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_UnionVebaMember |  |  |  |  |
Obligation at end of year | 391.5 us-gaap_DefinedBenefitPlanBenefitObligation / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_UnionVebaMember |  | 312.7 us-gaap_DefinedBenefitPlanBenefitObligation / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_UnionVebaMember |  |  |
Change in plan assets: |  |  |  |  |  |
Fair market value of plan assets at beginning of year | 717.5 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_UnionVebaMember |  |  |  |  |
Sale of Company's common stock by Union VEBA | 0 kalu_IncreaseInPostretirementMedicalPlanAsset / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_UnionVebaMember |  | 0 kalu_IncreaseInPostretirementMedicalPlanAsset / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_UnionVebaMember | [1] |  |
Fair market value of plan assets at end of year | 731.6 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_UnionVebaMember |  | 717.5 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_UnionVebaMember |  |  |
Net funded status | 340.1 us-gaap_DefinedBenefitPlanFundedStatusOfPlan / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_UnionVebaMember |  | 404.8 us-gaap_DefinedBenefitPlanFundedStatusOfPlan / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_UnionVebaMember |  |  |
Benefit Obligations and Funded Status Additional Disclosure |  |  |  |  |  |
Actuarial gain due to lower than expected drug claim costs | 18.0 kalu_ActuarialGainLossDueToChangesInPrescriptionDrugClaimCostsAndRetireeDrugSubsidyAssumptions / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_UnionVebaMember |  | 54.9 kalu_ActuarialGainLossDueToChangesInPrescriptionDrugClaimCostsAndRetireeDrugSubsidyAssumptions / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_UnionVebaMember |  |  |
Actuarial gain due to higher than expected mortality rate |  |  | (8.0)kalu_ActuarialGainLossDueToChangesInCensusData / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_UnionVebaMember |  |  |
Actuarial loss due to the addition of a new healthcare premium reimbursement benefit starting in 2014 | 60.5 kalu_PriorServiceCostDueToHealthcarePremiumReimbursementBenefit / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_UnionVebaMember |  |  |  |  |
Prior Service Cost Due to a New Death Benefit | 15.9 kalu_PriorServiceCostDuetoaNewDeathBenefit / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_UnionVebaMember |  |  |  |  |
Prior Service Cost Due to Increase in the Annual Healthcare Reimbursement |  |  | 63.8 kalu_PriorServiceCostDuetoIncreaseintheAnnualHealthcareReimbursement / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_UnionVebaMember |  |  |
Actuarial loss due to changes in administrative costs | 0.4 kalu_ActuarialGainLossDueToChangesInAdministrativeCosts / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_UnionVebaMember |  | 2.7 kalu_ActuarialGainLossDueToChangesInAdministrativeCosts / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_UnionVebaMember |  |  |
Net Funded Status |  |  |  |  |  |
Accumulated plan benefit obligation | (391.5)us-gaap_DefinedBenefitPlanBenefitObligation / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_UnionVebaMember |  | (312.7)us-gaap_DefinedBenefitPlanBenefitObligation / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_UnionVebaMember |  |  |
Plan assets | 731.6 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_UnionVebaMember |  | 717.5 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_UnionVebaMember |  |  |
Net funded status | 340.1 us-gaap_DefinedBenefitPlanFundedStatusOfPlan / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_UnionVebaMember |  | 404.8 us-gaap_DefinedBenefitPlanFundedStatusOfPlan / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_UnionVebaMember |  |  |
Union VEBA | Company Appointed |  |  |  |  |  |
Postretirement Medical Obligations |  |  |  |  |  |
Number of trustees | 2 kalu_NumberOfTrustees / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_UnionVebaMember / kalu_TrusteesAxis = kalu_CompanyAppointedMember |  |  |  |  |
Union VEBA | USW Appointed |  |  |  |  |  |
Postretirement Medical Obligations |  |  |  |  |  |
Number of trustees | 2 kalu_NumberOfTrustees / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_UnionVebaMember / kalu_TrusteesAxis = kalu_UswAppointedMember |  |  |  |  |
Salaried VEBA |  |  |  |  |  |
Postretirement Medical Obligations |  |  |  |  |  |
Percent allocation of total contribution between VEBAs | 14.50%kalu_PercentAllocationOfTotalContributionBetweenVebas / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_SalariedVebaMember |  |  |  |  |
Accrued annual VEBA contribution | 2.0 kalu_AccruedAnnualVebaContribution / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_SalariedVebaMember |  |  |  |  |
Assumptions used to determine benefit obligations |  |  |  |  |  |
Discount rate | 3.60%us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingBenefitObligationDiscountRate / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_SalariedVebaMember |  | 4.20%us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingBenefitObligationDiscountRate / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_SalariedVebaMember |  |  |
Assumptions used to determine net periodic benefit cost (income) |  |  |  |  |  |
Discount rate | 4.20%us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostDiscountRate / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_SalariedVebaMember |  | 3.40%us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostDiscountRate / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_SalariedVebaMember |  | 3.75%us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostDiscountRate / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_SalariedVebaMember |
Expected long-term return on plan assets | 7.75%us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostExpectedLongTermReturnOnAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_SalariedVebaMember | [10] | 7.25%us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostExpectedLongTermReturnOnAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_SalariedVebaMember | [10] | 7.25%us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostExpectedLongTermReturnOnAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_SalariedVebaMember | [10]
Change in benefit obligation: |  |  |  |  |  |
Obligation at beginning of year | 62.0 us-gaap_DefinedBenefitPlanBenefitObligation / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_SalariedVebaMember |  |  |  |  |
Obligation at end of year | 79.4 us-gaap_DefinedBenefitPlanBenefitObligation / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_SalariedVebaMember |  | 62.0 us-gaap_DefinedBenefitPlanBenefitObligation / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_SalariedVebaMember |  |  |
Change in plan assets: |  |  |  |  |  |
Fair market value of plan assets at beginning of year | 63.2 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_SalariedVebaMember |  |  |  |  |
Fair market value of plan assets at end of year | 62.2 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_SalariedVebaMember |  | 63.2 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_SalariedVebaMember |  |  |
Net funded status | (17.2)us-gaap_DefinedBenefitPlanFundedStatusOfPlan / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_SalariedVebaMember |  | 1.2 us-gaap_DefinedBenefitPlanFundedStatusOfPlan / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_SalariedVebaMember |  |  |
Benefit Obligations and Funded Status Additional Disclosure |  |  |  |  |  |
Prior Service Cost Due to Increase in the Annual Healthcare Reimbursement | 14.0 kalu_PriorServiceCostDuetoIncreaseintheAnnualHealthcareReimbursement / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_SalariedVebaMember |  |  |  |  |
Net Funded Status |  |  |  |  |  |
Accumulated plan benefit obligation | (79.4)us-gaap_DefinedBenefitPlanBenefitObligation / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_SalariedVebaMember |  | (62.0)us-gaap_DefinedBenefitPlanBenefitObligation / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_SalariedVebaMember |  |  |
Plan assets | 62.2 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_SalariedVebaMember |  | 63.2 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_SalariedVebaMember |  |  |
Net funded status | (17.2)us-gaap_DefinedBenefitPlanFundedStatusOfPlan / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_SalariedVebaMember |  | 1.2 us-gaap_DefinedBenefitPlanFundedStatusOfPlan / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_SalariedVebaMember |  |  |
Variable cash contribution | VEBAs |  |  |  |  |  |
Postretirement Medical Obligations |  |  |  |  |  |
Annual VEBA contribution paid | 16.0 kalu_AnnualVebaContributionPaid / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_VebasMember / kalu_TypesOfContributionsAxis = kalu_VariableCashContributionMember |  |  |  |  |
As Reported | VEBAs |  |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |  |
Defined Benefit Plan, Plan Amendments |  |  | 0 us-gaap_DefinedBenefitPlanPlanAmendments / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_VebasMember / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember | [1] |  |
Change in benefit obligation: |  |  |  |  |  |
Obligation at beginning of year |  |  | 384.1 us-gaap_DefinedBenefitPlanBenefitObligation / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_VebasMember / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember | [1] |  |
Foreign currency translation adjustment |  |  | 0 us-gaap_DefinedBenefitPlanForeignCurrencyExchangeRateChangesBenefitObligation / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_VebasMember / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember | [1] |  |
Service cost |  |  | 2.5 us-gaap_DefinedBenefitPlanServiceCost / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_VebasMember / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember | [1] |  |
Interest cost |  |  | 14.6 us-gaap_DefinedBenefitPlanInterestCost / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_VebasMember / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember | [1] |  |
Actuarial (gain) loss |  |  | (7.3)us-gaap_DefinedBenefitPlanActuarialGainLoss / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_VebasMember / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember | [1],[2] |  |
Plan participant contributions |  |  | 0 us-gaap_DefinedBenefitPlanContributionsByPlanParticipants / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_VebasMember / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember | [1] |  |
Benefits paid by VEBAs |  |  | (21.5)kalu_BenefitsPaidByVeba / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_VebasMember / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember | [1] |  |
Reimbursement from Retiree Drug Subsidy |  |  | 2.3 us-gaap_DefinedBenefitPlanGrossPrescriptionDrugSubsidyReceiptsReceived / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_VebasMember / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember | [1],[3] |  |
Obligation at end of year |  |  | 374.7 us-gaap_DefinedBenefitPlanBenefitObligation / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_VebasMember / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember | [1] |  |
Change in plan assets: |  |  |  |  |  |
Fair market value of plan assets at beginning of year |  |  | 744.7 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_VebasMember / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember | [1] |  |
Foreign currency translation adjustment |  |  | 0 us-gaap_DefinedBenefitPlanForeignCurrencyExchangeRateChangesPlanAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_VebasMember / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember | [1] |  |
Actual return on assets |  |  | 39.2 us-gaap_DefinedBenefitPlanActualReturnOnPlanAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_VebasMember / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember | [1] |  |
Plan participant contributions |  |  | 0 us-gaap_DefinedBenefitPlanContributionsByPlanParticipants / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_VebasMember / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember | [1] |  |
Employer/Company contributions |  |  | 16.0 us-gaap_DefinedBenefitPlanContributionsByEmployer / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_VebasMember / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember | [1],[4] |  |
Benefits paid by VEBAs |  |  | (21.5)kalu_BenefitsPaidByVeba / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_VebasMember / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember | [1] |  |
Reimbursement from Retiree Drug Subsidy |  |  | 2.3 us-gaap_DefinedBenefitPlanGrossPrescriptionDrugSubsidyReceiptsReceived / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_VebasMember / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember | [1],[3] |  |
Fair market value of plan assets at end of year |  |  | 780.7 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_VebasMember / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember | [1] |  |
Net funded status |  |  | 406.0 us-gaap_DefinedBenefitPlanFundedStatusOfPlan / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_VebasMember / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember | [1],[5] |  |
Net Funded Status |  |  |  |  |  |
Accumulated plan benefit obligation |  |  | (374.7)us-gaap_DefinedBenefitPlanBenefitObligation / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_VebasMember / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember | [1] |  |
Plan assets |  |  | 780.7 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_VebasMember / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember | [1] |  |
Net funded status |  |  | 406.0 us-gaap_DefinedBenefitPlanFundedStatusOfPlan / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_VebasMember / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember | [1],[5] |  |
Accumulated other comprehensive (loss) income |  |  |  |  |  |
Accumulated net actuarial (losses) gains |  |  | (0.5)us-gaap_DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeNetGainsLossesBeforeTax / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_VebasMember / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember |  |  |
Prior service cost |  |  | (32.7)us-gaap_DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeNetPriorServiceCostCreditBeforeTax / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_VebasMember / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember |  |  |
Loss recognized in Accumulated other comprehensive income (loss) |  |  | (33.2)us-gaap_DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeBeforeTax / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_VebasMember / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember |  |  |
Components of Net Periodic Benefit Cost (Income) |  |  |  |  |  |
Service cost |  |  | 2.5 us-gaap_DefinedBenefitPlanServiceCost / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_VebasMember / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember | [1] |  |
Interest cost |  |  | 14.6 us-gaap_DefinedBenefitPlanInterestCost / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_VebasMember / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember | [1] |  |
As Reported | Union VEBA |  |  |  |  |  |
Change in plan assets: |  |  |  |  |  |
Sale of Company's common stock by Union VEBA |  |  | $ 0 kalu_IncreaseInPostretirementMedicalPlanAsset / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = kalu_UnionVebaMember / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember | [1] |  |
[1] | The presentation of Change in benefit obligation in the table above has been revised from the prior year presentation to reflect separate amounts for actuarial gains and losses and prior service costs related to plan amendments. This information was presented in a footnote to the table in the prior year. The 2013 balances shown above were adjusted to reflect this reclassification. The impacts to the prospective amortization of Prior service cost and Actuarial loss (gain) were not material.
[2] | The actuarial gain relating to the VEBAs in 2014 was primarily comprised of (i) a gain of $53.6 due to projected lower benefit utilization; (ii) a gain of $18.0 due to projected lower drug claim cost in the future because of lower than expected drug claim costs in 2014 in the Union VEBA; (iii) a gain of $0.4 due primarily to a reduction in administrative cost in the Union VEBA; partially offset by (iv) a loss of $45.0 due primarily to reductions in the discount rates; and (v) a loss of $37.2 due primarily to updated actuarial mortality rates in both VEBAs.The actuarial gain relating to the VEBAs in 2013 was primarily comprised of (i) a gain of $54.9 due to projected lower drug claim cost in the future because of lower than expected drug claim costs in 2013 in the Union VEBA; (ii) a gain of $30.5 due to a decrease in discount rates used to determine benefit obligations for both VEBAs; (iii) a gain of $8.0 due primarily to a higher than expected mortality rate in the Union VEBA; partially offset by (iv) a loss of $2.7 due primarily to an increase in administrative cost in the Union VEBA.
[3] | The Union VEBA is eligible for the retiree drug subsidy of the Medicare Modernization Act that went into effect January 1, 2006. As a result, the Company has measured the Union VEBA’s obligations and costs to take into account this subsidy.
[4] | The Company accrued a liability for a variable cash contribution of $13.7 to the VEBAs with respect to calendar year 2014, which will be paid in the first quarter of 2015. The Company accrued a liability for a variable cash contribution of $16.0 to the VEBAs with respect to calendar year 2013, which was paid in the first quarter of 2014.
[5] | Prepaid benefits of $322.9 at December 31, 2014 was comprised of $340.1 presented as Net asset of VEBAs on the Consolidated Balance Sheet related to the Union VEBA, offset by $17.2 presented as Net liability in respect of VEBA related to the Salaried VEBA. Prepaid benefits of $406.0 relating to both VEBAs at December 31, 2013 were presented as Net asset of VEBAs on the Consolidated Balance Sheet.
[6] | Such amounts were obtained from the VEBAs. The Company's only financial obligations to the VEBAs are to pay the variable contributions, which may not exceed $20.0 annually, and certain administrative fees.
[7] | The Company amortizes prior service cost on a straight-line basis over the average remaining years of service to full eligibility for benefits of the active plan participants.
[8] | The medical trend rate assumptions used for the Union VEBA were provided by the Union VEBA and certain industry data were provided by the Company's actuaries. The trend rate is assumed to decline to 5% by 2019 at each of December 31, 2014 and December 31, 2013. A one-percentage-point increase in the assumed medical trend rates would increase the accumulated postretirement benefit obligation of the Union VEBA by $37.7 and $27.8 at December 31, 2014 and December 31, 2013, respectively. A one-percentage-point decrease in the assumed medical trend rates would decrease the accumulated postretirement benefit obligation of the Union VEBA by $29.9 and $22.7 at December 31, 2014 and December 31, 2013, respectively.
[9] | The medical trend rate assumptions used for the Union VEBA, which is currently paying certain prescription drug benefits, were provided by the Union VEBA and certain industry data were provided by the Company's actuaries. The trend rate is assumed to decline to 5% by 2019 for each of 2014, 2013 and 2012. A one-percentage-point increase in the assumed medical trend rates would increase the aggregate of the service and interest cost components of net periodic benefit costs by $2.6, $2.0 and $2.5 for 2014, 2013 and 2012, respectively. A one-percentage-point decrease in the assumed medical trend rates would decrease the aggregate of the service and interest cost components of net periodic benefit costs by $2.0, $1.5 and $2.0 for 2014, 2013 and 2012, respectively.
[10] | The expected long-term rate of return assumption is based on the targeted investment portfolios provided to the Company by the VEBAs’ trustees.

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- Definition For defined benefit pension plans, the actuarial present value of benefits (whether vested or nonvested) attributed by the pension benefit formula to employee service rendered before a specified date and based on employee service and compensation (if applicable) before that date. The accumulated benefit obligation differs from the projected benefit obligation in that it includes no assumption about future compensation levels. For plans with flat-benefit or nonpay-related pension benefit formulas, the accumulated benefit obligation and the projected benefit obligation are the same. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Accumulated Benefit Obligation -URI http://asc.fasb.org/extlink&oid=6503844 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (e) -URI http://asc.fasb.org/extlink&oid=35743120&loc=d3e1928-114920 + Details
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- Definition The difference between fair value of plan assets at the end of the period and the fair value at the beginning of the period, adjusted for contributions and payments of benefits during the period, and after adjusting for taxes and other expenses, as applicable. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Actual Return on Plan Assets (Component of Net Periodic Postretirement Benefit Cost) -URI http://asc.fasb.org/extlink&oid=6504192 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (b)(1) -URI http://asc.fasb.org/extlink&oid=35743120&loc=d3e1928-114920 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Actual Return on Plan Assets (Component of Net Periodic Pension Cost) -URI http://asc.fasb.org/extlink&oid=6504226 + Details
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- Definition The interest rate used to adjust for the time value of money for the plan. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (k)(1) -URI http://asc.fasb.org/extlink&oid=35743120&loc=d3e1928-114920 + Details
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- Definition Expected rate of compensation increases (for pay-related plans). + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (k)(2) -URI http://asc.fasb.org/extlink&oid=35743120&loc=d3e1928-114920 + Details
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- Definition An assumption as to the rate of return on plan assets reflecting the average rate of earnings expected on the funds invested or to be invested to provide for the benefits included in the benefit obligation. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 30 -Glossary Expected Long-Term Rate of Return on Plan Assets -URI http://asc.fasb.org/extlink&oid=6512013 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (k)(3) -URI http://asc.fasb.org/extlink&oid=35743120&loc=d3e1928-114920 + Details
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- Definition Expected rate of compensation increases (for pay-related plans). + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (k)(2) -URI http://asc.fasb.org/extlink&oid=35743120&loc=d3e1928-114920 + Details
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- Definition 1) For defined benefit pension plans, the benefit obligation is the projected benefit obligation, which is the actuarial present value as of a date of all benefits attributed by the pension benefit formula to employee service rendered prior to that date. 2) For other postretirement defined benefit plans, the benefit obligation is the accumulated postretirement benefit obligation, which is the actuarial present value of benefits attributed to employee service rendered to a particular date. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=35743120&loc=d3e1928-114920 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Projected Benefit Obligation -URI http://asc.fasb.org/extlink&oid=6522206 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Accumulated Postretirement Benefit Obligation -URI http://asc.fasb.org/extlink&oid=6503904 + Details
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- Definition The amount of payments made for which participants are entitled under a pension plan, including pension benefits, death benefits, and benefits due on termination of employment. Also includes payments made under a postretirement benefit plan, including prescription drug benefits, health care benefits, life insurance benefits, and legal, educational and advisory services. This item represents a periodic decrease to the plan obligations and a decrease to plan assets. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Postretirement Benefits -URI http://asc.fasb.org/extlink&oid=6521376 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 60 -Section 50 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=6414203&loc=d3e39716-114964 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 30 -Glossary Benefits -URI http://asc.fasb.org/extlink&oid=6506267 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 60 -Glossary Benefits -URI http://asc.fasb.org/extlink&oid=6506309 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (a)(6) -URI http://asc.fasb.org/extlink&oid=35743120&loc=d3e1928-114920 Reference 6: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (b)(5) -URI http://asc.fasb.org/extlink&oid=35743120&loc=d3e1928-114920 + Details
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- Definition The effect of a one-percentage-point increase in the assumed health care cost trend rates on the accumulated postretirement benefit obligation for health care benefits. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (m) -URI http://asc.fasb.org/extlink&oid=35743120&loc=d3e1928-114920 + Details
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- Definition Amount of benefits from a defined benefit plan expected to be paid in the fourth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (f) -URI http://asc.fasb.org/extlink&oid=35743120&loc=d3e1928-114920 + Details
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- Definition Amount of benefits from a defined benefit plan expected to be paid in the second fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (f) -URI http://asc.fasb.org/extlink&oid=35743120&loc=d3e1928-114920 + Details
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- Definition An amount calculated as a basis for determining the extent of delayed recognition of the effects of changes in the fair value of assets. The expected return on plan assets is determined based on the expected long-term rate of return on plan assets and the market-related value of plan assets. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 30 -Glossary Expected Return on Plan Assets -URI http://asc.fasb.org/extlink&oid=6512136 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 60 -Glossary Expected Return on Plan Assets -URI http://asc.fasb.org/extlink&oid=6512171 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (h)(3) -URI http://asc.fasb.org/extlink&oid=35743120&loc=d3e1928-114920 + Details
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- Definition Amount of gain (loss) from foreign currency exchange rate changes for benefit obligation for plans of a foreign operation whose functional currency is not the reporting currency. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (a)(5) -URI http://asc.fasb.org/extlink&oid=35743120&loc=d3e1928-114920 + Details
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- Definition Amount of the period's gross receipts received from the prescription drug subsidy, which is to be used in the roll forward of the accumulated postretirement benefit obligation of an applicable postretirement benefit plan. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 60 -Section 50 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=6414203&loc=d3e39716-114964 + Details
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- Definition The increase in a defined benefit pension plan's projected benefit obligation or a defined benefit postretirement plan's accumulated postretirement benefit obligation due to the passage of time. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (h)(2) -URI http://asc.fasb.org/extlink&oid=35743120&loc=d3e1928-114920 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (a)(2) -URI http://asc.fasb.org/extlink&oid=35743120&loc=d3e1928-114920 + Details
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