Quarterly report pursuant to Section 13 or 15(d)

OTHER COMPREHENSIVE INCOME (LOSS) (Details 2)

v2.4.1.9
OTHER COMPREHENSIVE INCOME (LOSS) (Details 2) (USD $)
In Millions, unless otherwise specified
 3 Months Ended
Mar. 29, 2015
Mar. 30, 2014
Reclassified out of accumulated other comprehensive income (loss) and related tax effects    
Other income (expense), net $ (9)us-gaap_OtherNonoperatingIncomeExpense $ (10)us-gaap_OtherNonoperatingIncomeExpense
NET SALES (4,709)us-gaap_SalesRevenueNet [1] (4,406)us-gaap_SalesRevenueNet [1]
Cost of sales (3,514)us-gaap_CostOfRevenue (3,307)us-gaap_CostOfRevenue
Total before taxes (548)us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest (511)us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest
Income tax expense 144us-gaap_IncomeTaxExpenseBenefit 153us-gaap_IncomeTaxExpenseBenefit
CONSOLIDATED NET INCOME (404)us-gaap_ProfitLoss (358)us-gaap_ProfitLoss
Reclassified out of accumulated other comprehensive income (loss)    
Reclassified out of accumulated other comprehensive income (loss) and related tax effects    
CONSOLIDATED NET INCOME 13us-gaap_ProfitLoss
/ us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeAxis
= us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeMember 		9us-gaap_ProfitLoss
/ us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeAxis
= us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeMember
Realized (gain) loss on marketable securities | Reclassified out of accumulated other comprehensive income (loss)    
Reclassified out of accumulated other comprehensive income (loss) and related tax effects    
Other income (expense), net (1)us-gaap_OtherNonoperatingIncomeExpense
/ us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeAxis
= us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeMember
/ us-gaap_StatementEquityComponentsAxis
= cmi_AccumulatedNetRealizedInvestmentGainLossMember 		(1)us-gaap_OtherNonoperatingIncomeExpense
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= us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeMember
/ us-gaap_StatementEquityComponentsAxis
= cmi_AccumulatedNetRealizedInvestmentGainLossMember
Income tax expense (1)us-gaap_IncomeTaxExpenseBenefit
/ us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeAxis
= us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeMember
/ us-gaap_StatementEquityComponentsAxis
= cmi_AccumulatedNetRealizedInvestmentGainLossMember 		 
CONSOLIDATED NET INCOME (2)us-gaap_ProfitLoss
/ us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeAxis
= us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeMember
/ us-gaap_StatementEquityComponentsAxis
= cmi_AccumulatedNetRealizedInvestmentGainLossMember 		(1)us-gaap_ProfitLoss
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= us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeMember
/ us-gaap_StatementEquityComponentsAxis
= cmi_AccumulatedNetRealizedInvestmentGainLossMember
Realized (gain) loss on derivatives | Foreign currency forward contracts | Reclassified out of accumulated other comprehensive income (loss)    
Reclassified out of accumulated other comprehensive income (loss) and related tax effects    
NET SALES   (2)us-gaap_SalesRevenueNet
/ us-gaap_DerivativeInstrumentRiskAxis
= us-gaap_ForeignExchangeContractMember
/ us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeAxis
= us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeMember
/ us-gaap_StatementEquityComponentsAxis
= us-gaap_AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedgesMember
Realized (gain) loss on derivatives | Commodity swap contracts | Reclassified out of accumulated other comprehensive income (loss)    
Reclassified out of accumulated other comprehensive income (loss) and related tax effects    
Cost of sales   2us-gaap_CostOfRevenue
/ us-gaap_DerivativeInstrumentRiskAxis
= us-gaap_CommodityContractMember
/ us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeAxis
= us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeMember
/ us-gaap_StatementEquityComponentsAxis
= us-gaap_AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedgesMember
Pension and other postretirement defined benefit plans | Reclassified out of accumulated other comprehensive income (loss)    
Reclassified out of accumulated other comprehensive income (loss) and related tax effects    
Recognized actuarial loss 22us-gaap_OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetGainLossBeforeTax
/ us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeAxis
= us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeMember
/ us-gaap_StatementEquityComponentsAxis
= us-gaap_AccumulatedDefinedBenefitPlansAdjustmentMember 		[2] 15us-gaap_OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetGainLossBeforeTax
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= us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeMember
/ us-gaap_StatementEquityComponentsAxis
= us-gaap_AccumulatedDefinedBenefitPlansAdjustmentMember 		[2]
Total before taxes 22us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest
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= us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeMember
/ us-gaap_StatementEquityComponentsAxis
= us-gaap_AccumulatedDefinedBenefitPlansAdjustmentMember 		15us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest
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= us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeMember
/ us-gaap_StatementEquityComponentsAxis
= us-gaap_AccumulatedDefinedBenefitPlansAdjustmentMember
Income tax expense (7)us-gaap_IncomeTaxExpenseBenefit
/ us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeAxis
= us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeMember
/ us-gaap_StatementEquityComponentsAxis
= us-gaap_AccumulatedDefinedBenefitPlansAdjustmentMember 		(5)us-gaap_IncomeTaxExpenseBenefit
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/ us-gaap_StatementEquityComponentsAxis
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CONSOLIDATED NET INCOME $ 15us-gaap_ProfitLoss
/ us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeAxis
= us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeMember
/ us-gaap_StatementEquityComponentsAxis
= us-gaap_AccumulatedDefinedBenefitPlansAdjustmentMember 		$ 10us-gaap_ProfitLoss
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= us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeMember
/ us-gaap_StatementEquityComponentsAxis
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[1] Includes sales to nonconsolidated equity investees of $325 million and $592 million for the three month periods ended March 29, 2015 and March 30, 2014, respectively.
[2] These accumulated other comprehensive income components are included in the computation of net periodic pension cost (see Note 3, ''PENSION AND OTHER POSTRETIREMENT BENEFITS'').