XML 92 R63.htm IDEA: XBRL DOCUMENT v2.4.1.9
Pension and Postretirement Plans (Details) (USD $)
In Millions, unless otherwise specified
12 Months Ended
Dec. 31, 2014
Dec. 31, 2013
Dec. 31, 2012
Defined Benefit Plan Disclosure [Line Items]      
Defined Contribution Plan, Cost Recognized $ 6.7us-gaap_DefinedContributionPlanCostRecognized $ 6.6us-gaap_DefinedContributionPlanCostRecognized $ 6.9us-gaap_DefinedContributionPlanCostRecognized
Curtailment gain 0us-gaap_DefinedBenefitPlanRecognizedNetGainLossDueToCurtailments (0.6)us-gaap_DefinedBenefitPlanRecognizedNetGainLossDueToCurtailments 0us-gaap_DefinedBenefitPlanRecognizedNetGainLossDueToCurtailments
Reduction to pension obligation   10.3us-gaap_IncreaseDecreaseInPensionPlanObligations  
Reduction to postretirement liability   26.1us-gaap_IncreaseDecreaseInPostretirementObligations  
Capitalized portion of defined benefit contribution percent 8.00%cbb_CapitalizedPortionOfDefinedBenefitContributionPercent 10.00%cbb_CapitalizedPortionOfDefinedBenefitContributionPercent 11.00%cbb_CapitalizedPortionOfDefinedBenefitContributionPercent
Fair value of plan assets 435.3us-gaap_DefinedBenefitPlanFairValueOfPlanAssets 410.6us-gaap_DefinedBenefitPlanFairValueOfPlanAssets  
Defined Benefit Plan, Amounts Recognized in Balance Sheet [Abstract]      
Pension and postretirement benefit obligations (noncurrent liablity) 240.1us-gaap_PensionAndOtherPostretirementDefinedBenefitPlansLiabilitiesNoncurrent 202.7us-gaap_PensionAndOtherPostretirementDefinedBenefitPlansLiabilitiesNoncurrent  
Defined Benefit Plan, Assets, Target Allocations [Abstract]      
Allocation Percentage in US based Investments 78.00%cbb_DefinedBenefitPlanAllocationPercentageInUnitedStatesBasedInvestments    
Disclosure of Expected Gross Prescription Drug Subsidy Receipts [Abstract]      
2015 (0.6)us-gaap_PrescriptionDrugSubsidyReceiptsNextTwelveMonths    
2016 (0.6)us-gaap_PrescriptionDrugSubsidyReceiptsYearTwo1    
2017 (0.5)us-gaap_PrescriptionDrugSubsidyReceiptsYearThree1    
2018 (0.5)us-gaap_PrescriptionDrugSubsidyReceiptsYearFour1    
2019 (0.5)us-gaap_PrescriptionDrugSubsidyReceiptsYearFive1    
Years 2020 - 2024 (2.0)us-gaap_PrescriptionDrugSubsidyReceiptsAfterYearFive    
Pension Plan [Member]      
Defined Benefit Plan Disclosure [Line Items]      
Curtailment gain 0us-gaap_DefinedBenefitPlanRecognizedNetGainLossDueToCurtailments
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_PensionPlansDefinedBenefitMember
(0.6)us-gaap_DefinedBenefitPlanRecognizedNetGainLossDueToCurtailments
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_PensionPlansDefinedBenefitMember
0us-gaap_DefinedBenefitPlanRecognizedNetGainLossDueToCurtailments
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_PensionPlansDefinedBenefitMember
Fair value of plan assets 424.3us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_PensionPlansDefinedBenefitMember
399.3us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_PensionPlansDefinedBenefitMember
343.8us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_PensionPlansDefinedBenefitMember
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Benefit Obligation [Abstract]      
Discount rate 3.40%us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingBenefitObligationDiscountRate
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_PensionPlansDefinedBenefitMember
4.20%us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingBenefitObligationDiscountRate
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_PensionPlansDefinedBenefitMember
 
Expected long-term rate of return 7.75%cbb_DefinedBenefitPlanAssumptionsUsedCalculatingBenefitObligationExpectedLongTermRateOfReturnOnAssets
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_PensionPlansDefinedBenefitMember
7.75%cbb_DefinedBenefitPlanAssumptionsUsedCalculatingBenefitObligationExpectedLongTermRateOfReturnOnAssets
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_PensionPlansDefinedBenefitMember
 
Future compensation growth rate 0.00%us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingBenefitObligationRateOfCompensationIncrease
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_PensionPlansDefinedBenefitMember
0.00%us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingBenefitObligationRateOfCompensationIncrease
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_PensionPlansDefinedBenefitMember
 
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Purchases, Sales, Issuances, Settlements [Abstract]      
Balance, beginning of the year 30.8us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_PensionPlansDefinedBenefitMember
27.8us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_PensionPlansDefinedBenefitMember
 
Realized gains, net 3.2us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInOtherComprehensiveIncomeLoss
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_PensionPlansDefinedBenefitMember
1.0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInOtherComprehensiveIncomeLoss
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_PensionPlansDefinedBenefitMember
 
Unrealized gains, net 0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetPeriodIncreaseDecrease
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_PensionPlansDefinedBenefitMember
2.7us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetPeriodIncreaseDecrease
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_PensionPlansDefinedBenefitMember
 
Purchases, sales, issuances and settlements, net (34.0)us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetPurchasesSalesIssuancesSettlements
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_PensionPlansDefinedBenefitMember
(0.7)us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetPurchasesSalesIssuancesSettlements
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_PensionPlansDefinedBenefitMember
 
Balance, end of the year 0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_PensionPlansDefinedBenefitMember
30.8us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_PensionPlansDefinedBenefitMember
27.8us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_PensionPlansDefinedBenefitMember
Defined Benefit Plan, Amounts Recognized in Balance Sheet [Abstract]      
Accrued payroll and benefits (current liability) 2.2us-gaap_PensionAndOtherPostretirementDefinedBenefitPlansCurrentLiabilities
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_PensionPlansDefinedBenefitMember
2.1us-gaap_PensionAndOtherPostretirementDefinedBenefitPlansCurrentLiabilities
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_PensionPlansDefinedBenefitMember
 
Pension and postretirement benefit obligations (noncurrent liablity) 150.8us-gaap_PensionAndOtherPostretirementDefinedBenefitPlansLiabilitiesNoncurrent
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_PensionPlansDefinedBenefitMember
121.6us-gaap_PensionAndOtherPostretirementDefinedBenefitPlansLiabilitiesNoncurrent
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_PensionPlansDefinedBenefitMember
 
Total 153.0us-gaap_PensionAndOtherPostretirementDefinedBenefitPlansLiabilitiesCurrentAndNoncurrent
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_PensionPlansDefinedBenefitMember
123.7us-gaap_PensionAndOtherPostretirementDefinedBenefitPlansLiabilitiesCurrentAndNoncurrent
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_PensionPlansDefinedBenefitMember
 
Defined Benefit Plan, Net Periodic Benefit Cost [Abstract]      
Service cost 1.0us-gaap_DefinedBenefitPlanServiceCost
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_PensionPlansDefinedBenefitMember
2.1us-gaap_DefinedBenefitPlanServiceCost
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_PensionPlansDefinedBenefitMember
2.6us-gaap_DefinedBenefitPlanServiceCost
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_PensionPlansDefinedBenefitMember
Interest cost on projected benefit obligation 21.0us-gaap_DefinedBenefitPlanInterestCost
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_PensionPlansDefinedBenefitMember
18.8us-gaap_DefinedBenefitPlanInterestCost
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_PensionPlansDefinedBenefitMember
21.3us-gaap_DefinedBenefitPlanInterestCost
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_PensionPlansDefinedBenefitMember
Expected return on plan assets (28.1)us-gaap_DefinedBenefitPlanExpectedReturnOnPlanAssets
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_PensionPlansDefinedBenefitMember
(25.7)us-gaap_DefinedBenefitPlanExpectedReturnOnPlanAssets
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_PensionPlansDefinedBenefitMember
(26.1)us-gaap_DefinedBenefitPlanExpectedReturnOnPlanAssets
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_PensionPlansDefinedBenefitMember
Amortization of:      
Prior service cost (benefit) 0.2us-gaap_DefinedBenefitPlanAmortizationOfPriorServiceCostCredit
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_PensionPlansDefinedBenefitMember
0.2us-gaap_DefinedBenefitPlanAmortizationOfPriorServiceCostCredit
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_PensionPlansDefinedBenefitMember
0.1us-gaap_DefinedBenefitPlanAmortizationOfPriorServiceCostCredit
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_PensionPlansDefinedBenefitMember
Actuarial loss 17.3us-gaap_DefinedBenefitPlanAmortizationOfGainsLosses
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_PensionPlansDefinedBenefitMember
22.0us-gaap_DefinedBenefitPlanAmortizationOfGainsLosses
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_PensionPlansDefinedBenefitMember
19.4us-gaap_DefinedBenefitPlanAmortizationOfGainsLosses
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_PensionPlansDefinedBenefitMember
Pension/postretirement costs 11.4us-gaap_DefinedBenefitPlanNetPeriodicBenefitCost
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_PensionPlansDefinedBenefitMember
16.8us-gaap_DefinedBenefitPlanNetPeriodicBenefitCost
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_PensionPlansDefinedBenefitMember
17.3us-gaap_DefinedBenefitPlanNetPeriodicBenefitCost
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_PensionPlansDefinedBenefitMember
Defined Benefit Plan, Estimated Future Benefit Payments [Abstract]      
2015 41.3us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsNextTwelveMonths
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_PensionPlansDefinedBenefitMember
   
2016 41.3us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearTwo
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_PensionPlansDefinedBenefitMember
   
2017 41.1us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearThree
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_PensionPlansDefinedBenefitMember
   
2018 41.0us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearFour
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_PensionPlansDefinedBenefitMember
   
2019 39.5us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearFive
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_PensionPlansDefinedBenefitMember
   
Years 2020-2024 182.7us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsFiveFiscalYearsThereafter
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_PensionPlansDefinedBenefitMember
   
Other Postretirement Benefit Plan [Member]      
Defined Benefit Plan Disclosure [Line Items]      
Curtailment gain 0us-gaap_DefinedBenefitPlanRecognizedNetGainLossDueToCurtailments
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember
0us-gaap_DefinedBenefitPlanRecognizedNetGainLossDueToCurtailments
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember
0us-gaap_DefinedBenefitPlanRecognizedNetGainLossDueToCurtailments
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember
Fair value of plan assets 11.0us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember
11.3us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember
11.7us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Benefit Obligation [Abstract]      
Discount rate 3.40%us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingBenefitObligationDiscountRate
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember
4.10%us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingBenefitObligationDiscountRate
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember
 
Expected long-term rate of return 0.00%cbb_DefinedBenefitPlanAssumptionsUsedCalculatingBenefitObligationExpectedLongTermRateOfReturnOnAssets
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember
0.00%cbb_DefinedBenefitPlanAssumptionsUsedCalculatingBenefitObligationExpectedLongTermRateOfReturnOnAssets
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember
 
Future compensation growth rate 0.00%us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingBenefitObligationRateOfCompensationIncrease
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember
0.00%us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingBenefitObligationRateOfCompensationIncrease
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember
 
Pension and Other Postretirement Benefit Contributions [Abstract]      
Estimated Future Employer Contributions in Next Fiscal Year 12us-gaap_DefinedBenefitPlansEstimatedFutureEmployerContributionsInNextFiscalYear
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember
   
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Purchases, Sales, Issuances, Settlements [Abstract]      
Balance, beginning of the year 11.3us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember
11.7us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember
 
Realized gains, net 0.4us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInOtherComprehensiveIncomeLoss
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember
0.4us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInOtherComprehensiveIncomeLoss
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember
 
Unrealized gains, net 0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetPeriodIncreaseDecrease
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember
0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetPeriodIncreaseDecrease
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember
 
Purchases, sales, issuances and settlements, net (0.7)us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetPurchasesSalesIssuancesSettlements
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember
(0.8)us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetPurchasesSalesIssuancesSettlements
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember
 
Balance, end of the year 11.0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember
11.3us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember
11.7us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember
Defined Benefit Plan, Amounts Recognized in Balance Sheet [Abstract]      
Accrued payroll and benefits (current liability) 12.0us-gaap_PensionAndOtherPostretirementDefinedBenefitPlansCurrentLiabilities
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember
12.7us-gaap_PensionAndOtherPostretirementDefinedBenefitPlansCurrentLiabilities
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember
 
Pension and postretirement benefit obligations (noncurrent liablity) 86.0us-gaap_PensionAndOtherPostretirementDefinedBenefitPlansLiabilitiesNoncurrent
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember
77.5us-gaap_PensionAndOtherPostretirementDefinedBenefitPlansLiabilitiesNoncurrent
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember
 
Total 98.0us-gaap_PensionAndOtherPostretirementDefinedBenefitPlansLiabilitiesCurrentAndNoncurrent
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember
90.2us-gaap_PensionAndOtherPostretirementDefinedBenefitPlansLiabilitiesCurrentAndNoncurrent
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember
 
Defined Benefit Plan, Net Periodic Benefit Cost [Abstract]      
Service cost 0.3us-gaap_DefinedBenefitPlanServiceCost
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember
0.4us-gaap_DefinedBenefitPlanServiceCost
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember
0.5us-gaap_DefinedBenefitPlanServiceCost
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember
Interest cost on projected benefit obligation 4.0us-gaap_DefinedBenefitPlanInterestCost
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember
4.0us-gaap_DefinedBenefitPlanInterestCost
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember
5.6us-gaap_DefinedBenefitPlanInterestCost
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember
Expected return on plan assets 0us-gaap_DefinedBenefitPlanExpectedReturnOnPlanAssets
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember
0us-gaap_DefinedBenefitPlanExpectedReturnOnPlanAssets
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember
0us-gaap_DefinedBenefitPlanExpectedReturnOnPlanAssets
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember
Amortization of:      
Prior service cost (benefit) (15.4)us-gaap_DefinedBenefitPlanAmortizationOfPriorServiceCostCredit
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(14.1)us-gaap_DefinedBenefitPlanAmortizationOfPriorServiceCostCredit
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(13.2)us-gaap_DefinedBenefitPlanAmortizationOfPriorServiceCostCredit
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Pension/postretirement costs (5.7)us-gaap_DefinedBenefitPlanNetPeriodicBenefitCost
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(4.1)us-gaap_DefinedBenefitPlanNetPeriodicBenefitCost
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(0.3)us-gaap_DefinedBenefitPlanNetPeriodicBenefitCost
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Defined Benefit Plan, Estimated Future Benefit Payments [Abstract]      
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2016 11.7us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearTwo
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2017 10.7us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearThree
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2018 10.0us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearFour
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2019 8.2us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearFive
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Pension Plan Qualified [Member]      
Pension and Other Postretirement Benefit Contributions [Abstract]      
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42.1us-gaap_PensionAndOtherPostretirementBenefitContributions
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23.9us-gaap_PensionAndOtherPostretirementBenefitContributions
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Pension Plan Non-Qualified [Member]      
Pension and Other Postretirement Benefit Contributions [Abstract]      
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2.0us-gaap_PensionAndOtherPostretirementBenefitContributions
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Equity Funds [Member]      
Defined Benefit Plan Disclosure [Line Items]      
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57.0us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
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Fixed Income Funds [Member]      
Defined Benefit Plan Disclosure [Line Items]      
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109.8us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
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Defined Benefit Plan Disclosure [Line Items]      
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Defined Benefit Plan Disclosure [Line Items]      
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Insurance Contract, Rights and Obligations [Member]      
Defined Benefit Plan Disclosure [Line Items]      
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11.3us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
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Fair Value, Inputs, Level 1 [Member]      
Defined Benefit Plan Disclosure [Line Items]      
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Defined Benefit Plan Disclosure [Line Items]      
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Fair Value, Inputs, Level 1 [Member] | Equity Index Funds International [Member]      
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Fair Value, Inputs, Level 1 [Member] | Fixed Income Funds [Member]      
Defined Benefit Plan Disclosure [Line Items]      
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Fair Value, Inputs, Level 1 [Member] | Money Market Funds [Member]      
Defined Benefit Plan Disclosure [Line Items]      
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Fair Value, Inputs, Level 1 [Member] | Real Estate Funds [Member]      
Defined Benefit Plan Disclosure [Line Items]      
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Fair Value, Inputs, Level 1 [Member] | Insurance Contract, Rights and Obligations [Member]      
Defined Benefit Plan Disclosure [Line Items]      
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Defined Benefit Plan Disclosure [Line Items]      
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Defined Benefit Plan Disclosure [Line Items]      
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Defined Benefit Plan Disclosure [Line Items]      
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Defined Benefit Plan Disclosure [Line Items]      
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Defined Benefit Plan Disclosure [Line Items]      
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Defined Benefit Plan Disclosure [Line Items]      
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Defined Benefit Plan Disclosure [Line Items]      
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42.1us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
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Fair Value, Inputs, Level 3 [Member] | Equity Funds [Member]      
Defined Benefit Plan Disclosure [Line Items]      
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Fair Value, Inputs, Level 3 [Member] | Equity Index Funds International [Member]      
Defined Benefit Plan Disclosure [Line Items]      
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Fair Value, Inputs, Level 3 [Member] | Fixed Income Funds [Member]      
Defined Benefit Plan Disclosure [Line Items]      
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Fair Value, Inputs, Level 3 [Member] | Money Market Funds [Member]      
Defined Benefit Plan Disclosure [Line Items]      
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Fair Value, Inputs, Level 3 [Member] | Real Estate Funds [Member]      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets   30.8us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
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Fair Value, Inputs, Level 3 [Member] | Insurance Contract, Rights and Obligations [Member]      
Defined Benefit Plan Disclosure [Line Items]      
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