XML 65 R41.htm IDEA: XBRL DOCUMENT v2.4.1.9
BENEFIT PLANS: (Details) (USD $)
In Millions, unless otherwise specified
3 Months Ended
Mar. 31, 2015
Mar. 31, 2014
BENEFIT PLANS:    
Number of expatriate noncontributory defined benefit pension plans 2scco_DefinedBenefitPlanNumberOfExpatriateNoncontributoryPlans  
Post retirement defined benefit plan    
Defined benefit plan, net periodic benefit cost    
Service cost $ 0.2us-gaap_DefinedBenefitPlanServiceCost
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember
$ 0.3us-gaap_DefinedBenefitPlanServiceCost
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember
Interest cost 0.2us-gaap_DefinedBenefitPlanInterestCost
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember
0.3us-gaap_DefinedBenefitPlanInterestCost
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember
Expected return on plan assets (0.7)us-gaap_DefinedBenefitPlanExpectedReturnOnPlanAssets
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember
(0.9)us-gaap_DefinedBenefitPlanExpectedReturnOnPlanAssets
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember
Amortization of net actuarial loss   (0.2)scco_DefinedBenefitPlanAmortizationOfActuarialLoss
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember
Net periodic benefit costs (0.3)us-gaap_DefinedBenefitPlanNetPeriodicBenefitCost
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember
(0.5)us-gaap_DefinedBenefitPlanNetPeriodicBenefitCost
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember
Post retirement defined benefit plan | Maximum    
Defined benefit plan, net periodic benefit cost    
Amortization of net actuarial loss 0.1scco_DefinedBenefitPlanAmortizationOfActuarialLoss
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember
/ us-gaap_RangeAxis
= us-gaap_MaximumMember
 
Amortization of net loss (gain) (0.1)us-gaap_DefinedBenefitPlanAmortizationOfGainsLosses
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember
/ us-gaap_RangeAxis
= us-gaap_MaximumMember
(0.1)us-gaap_DefinedBenefitPlanAmortizationOfGainsLosses
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember
/ us-gaap_RangeAxis
= us-gaap_MaximumMember
Post-retirement Health Care Plan    
Defined benefit plan, net periodic benefit cost    
Interest cost 0.3us-gaap_DefinedBenefitPlanInterestCost
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= scco_DefinedBenefitPostretirementHealthCarePlanMember
0.3us-gaap_DefinedBenefitPlanInterestCost
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= scco_DefinedBenefitPostretirementHealthCarePlanMember
Amortization of net loss (gain) (0.1)us-gaap_DefinedBenefitPlanAmortizationOfGainsLosses
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= scco_DefinedBenefitPostretirementHealthCarePlanMember
 
Net periodic benefit costs 0.2us-gaap_DefinedBenefitPlanNetPeriodicBenefitCost
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= scco_DefinedBenefitPostretirementHealthCarePlanMember
0.3us-gaap_DefinedBenefitPlanNetPeriodicBenefitCost
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= scco_DefinedBenefitPostretirementHealthCarePlanMember
Post-retirement Health Care Plan | Maximum    
Defined benefit plan, net periodic benefit cost    
Amortization of net loss (gain)   (0.1)us-gaap_DefinedBenefitPlanAmortizationOfGainsLosses
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= scco_DefinedBenefitPostretirementHealthCarePlanMember
/ us-gaap_RangeAxis
= us-gaap_MaximumMember
Amortization of prior service cost (credit) $ 0.1us-gaap_DefinedBenefitPlanAmortizationOfPriorServiceCostCredit
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= scco_DefinedBenefitPostretirementHealthCarePlanMember
/ us-gaap_RangeAxis
= us-gaap_MaximumMember
$ 0.1us-gaap_DefinedBenefitPlanAmortizationOfPriorServiceCostCredit
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= scco_DefinedBenefitPostretirementHealthCarePlanMember
/ us-gaap_RangeAxis
= us-gaap_MaximumMember