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BENEFIT PLANS: (Details 2) (USD $) In Millions, except Per Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Post retirement defined benefit plan | Expatriate Plan
Benefit plans
Net asset value (in dollars per share)	$ 1.00scco_NetAssetValuePerShare / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember / us-gaap_PlanNameAxis = scco_ExpatriatePlanMember
Assumptions used to determine the pension obligation and seniority premiums as of year-end and the net cost in the ensuing year
Discount rate (as a percent)	3.50%scco_DefinedBenefitPlanAssumptionsUsedInCalculatingBenefitObligationAndNetPeriodicBenefitCostDiscountRate / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember / us-gaap_PlanNameAxis = scco_ExpatriatePlanMember	4.25%scco_DefinedBenefitPlanAssumptionsUsedInCalculatingBenefitObligationAndNetPeriodicBenefitCostDiscountRate / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember / us-gaap_PlanNameAxis = scco_ExpatriatePlanMember	3.35%scco_DefinedBenefitPlanAssumptionsUsedInCalculatingBenefitObligationAndNetPeriodicBenefitCostDiscountRate / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember / us-gaap_PlanNameAxis = scco_ExpatriatePlanMember
Expected long-term rate of return on plan asset (as a percent)	4.50%scco_DefinedBenefitPlanAssumptionsUsedInCalculatingBenefitObligationAndNetPeriodicBenefitCostExpectedLongTermReturnOnAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember / us-gaap_PlanNameAxis = scco_ExpatriatePlanMember	4.50%scco_DefinedBenefitPlanAssumptionsUsedInCalculatingBenefitObligationAndNetPeriodicBenefitCostExpectedLongTermReturnOnAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember / us-gaap_PlanNameAxis = scco_ExpatriatePlanMember	4.50%scco_DefinedBenefitPlanAssumptionsUsedInCalculatingBenefitObligationAndNetPeriodicBenefitCostExpectedLongTermReturnOnAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember / us-gaap_PlanNameAxis = scco_ExpatriatePlanMember
Post retirement defined benefit plan | Mexican Health Plan
Assumptions used to determine the pension obligation and seniority premiums as of year-end and the net cost in the ensuing year
Discount rate (as a percent)	6.70%scco_DefinedBenefitPlanAssumptionsUsedInCalculatingBenefitObligationAndNetPeriodicBenefitCostDiscountRate / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember / us-gaap_PlanNameAxis = scco_MexicanPlanMember	7.10%scco_DefinedBenefitPlanAssumptionsUsedInCalculatingBenefitObligationAndNetPeriodicBenefitCostDiscountRate / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember / us-gaap_PlanNameAxis = scco_MexicanPlanMember	6.50%scco_DefinedBenefitPlanAssumptionsUsedInCalculatingBenefitObligationAndNetPeriodicBenefitCostDiscountRate / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember / us-gaap_PlanNameAxis = scco_MexicanPlanMember
Expected long-term rate of return on plan asset (as a percent)	6.70%scco_DefinedBenefitPlanAssumptionsUsedInCalculatingBenefitObligationAndNetPeriodicBenefitCostExpectedLongTermReturnOnAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember / us-gaap_PlanNameAxis = scco_MexicanPlanMember	7.10%scco_DefinedBenefitPlanAssumptionsUsedInCalculatingBenefitObligationAndNetPeriodicBenefitCostExpectedLongTermReturnOnAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember / us-gaap_PlanNameAxis = scco_MexicanPlanMember	6.50%scco_DefinedBenefitPlanAssumptionsUsedInCalculatingBenefitObligationAndNetPeriodicBenefitCostExpectedLongTermReturnOnAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember / us-gaap_PlanNameAxis = scco_MexicanPlanMember
Number of financial institutions managing plan assets	3scco_DefinedBenefitPlanNumberOfFinancialInstitutionsManagingPlanAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember / us-gaap_PlanNameAxis = scco_MexicanPlanMember
Plan obligations as a percentage of benefit obligation	30.00%scco_DefinedBenefitPlanPlanObligationAsPercentageOfBenefitObligation / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember / us-gaap_PlanNameAxis = scco_MexicanPlanMember
Asset allocation (as a percent)	100.00%us-gaap_DefinedBenefitPlanWeightedAverageAssetAllocations / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember / us-gaap_PlanNameAxis = scco_MexicanPlanMember	100.00%us-gaap_DefinedBenefitPlanWeightedAverageAssetAllocations / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember / us-gaap_PlanNameAxis = scco_MexicanPlanMember
Expected employer contribution in next fiscal year	$ 6.3us-gaap_DefinedBenefitPlansEstimatedFutureEmployerContributionsInNextFiscalYear / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember / us-gaap_PlanNameAxis = scco_MexicanPlanMember
Pending payments to former Buenavista workers	$ 3.4scco_DefinedBenefitPlanBuyoutPaymentsOutstandingToWorkers / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember / us-gaap_PlanNameAxis = scco_MexicanPlanMember
Post retirement defined benefit plan | Parent Company (Grupo Mexico) common shares | Mexican Health Plan
Assumptions used to determine the pension obligation and seniority premiums as of year-end and the net cost in the ensuing year
Asset allocation (as a percent)	73.00%us-gaap_DefinedBenefitPlanWeightedAverageAssetAllocations / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember / dei_LegalEntityAxis = us-gaap_ParentCompanyMember / us-gaap_PlanNameAxis = scco_MexicanPlanMember
Post retirement defined benefit plan | Equity securities | Mexican Health Plan
Assumptions used to determine the pension obligation and seniority premiums as of year-end and the net cost in the ensuing year
Asset allocation (as a percent)	73.00%us-gaap_DefinedBenefitPlanWeightedAverageAssetAllocations / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_EquitySecuritiesMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember / us-gaap_PlanNameAxis = scco_MexicanPlanMember	74.00%us-gaap_DefinedBenefitPlanWeightedAverageAssetAllocations / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_EquitySecuritiesMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember / us-gaap_PlanNameAxis = scco_MexicanPlanMember
Post retirement defined benefit plan | Treasury bills | Mexican Health Plan
Assumptions used to determine the pension obligation and seniority premiums as of year-end and the net cost in the ensuing year
Asset allocation (as a percent)	27.00%us-gaap_DefinedBenefitPlanWeightedAverageAssetAllocations / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = scco_MexicanTreasuryBillSecuritiesMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember / us-gaap_PlanNameAxis = scco_MexicanPlanMember	26.00%us-gaap_DefinedBenefitPlanWeightedAverageAssetAllocations / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = scco_MexicanTreasuryBillSecuritiesMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember / us-gaap_PlanNameAxis = scco_MexicanPlanMember
Post-retirement Health Care Plan | Expatriate Plan
Assumptions used to determine the pension obligation and seniority premiums as of year-end and the net cost in the ensuing year
Discount rate (as a percent)	3.50%scco_DefinedBenefitPlanAssumptionsUsedInCalculatingBenefitObligationAndNetPeriodicBenefitCostDiscountRate / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = scco_DefinedBenefitPostretirementHealthCarePlanMember / us-gaap_PlanNameAxis = scco_ExpatriatePlanMember	4.25%scco_DefinedBenefitPlanAssumptionsUsedInCalculatingBenefitObligationAndNetPeriodicBenefitCostDiscountRate / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = scco_DefinedBenefitPostretirementHealthCarePlanMember / us-gaap_PlanNameAxis = scco_ExpatriatePlanMember	4.25%scco_DefinedBenefitPlanAssumptionsUsedInCalculatingBenefitObligationAndNetPeriodicBenefitCostDiscountRate / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = scco_DefinedBenefitPostretirementHealthCarePlanMember / us-gaap_PlanNameAxis = scco_ExpatriatePlanMember

X

- Definition

Represents the interest rate used to adjust for the time value of money assumed to determine the pension obligation and seniority premiums as of the year-end and the net cost.

+ References

No definition available.

+ Details

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X

- 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 determine the pension obligation and seniority premiums as of year-end and the net cost.

+ References

No definition available.

+ Details

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Namespace Prefix:	scco_
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X

- Definition

Represents the buyout payments outstanding to workers under defined benefit plans.

+ References

No definition available.

+ Details

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Balance Type:	debit
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X

- Definition

Represents the number of financial institutions managing the plan assets.

+ References

No definition available.

+ Details

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X

- Definition

Represents the plan obligation as a percentage of the entity's aggregate defined benefit obligation.

+ References

No definition available.

+ Details

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X

- Definition

Represents the company's net asset value per share.

+ References

No definition available.

+ Details

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Namespace Prefix:	scco_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	instant

X

- Details

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X

- Definition

Amount of employer's best estimate of contributions expected to be paid to the plan during the next fiscal year beginning after the date of the latest statement of financial position.

+ 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 (g)

-URI http://asc.fasb.org/extlink&oid=35743120&loc=d3e1928-114920

+ Details

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Balance Type:	debit
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X

- Definition

Percentage of fair value of investments (categorized by debt securities, equity securities, real estate and other plan assets) to the fair value of plan assets held.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 5

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=35743120&loc=d3e2446-114920



Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (d)(1)

-URI http://asc.fasb.org/extlink&oid=35743120&loc=d3e1928-114920

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