Southern Copper (SCCO) 10-K 1 Mar 18 2017 FY Annual report Financial data

Document and Entity Information

Document and Entity Information - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Feb. 23, 2018	Jun. 30, 2017
Document and Entity Information
Entity Registrant Name	SOUTHERN COPPER CORP/
Entity Central Index Key	1,001,838
Document Type	10-K
Document Period End Date	Dec. 31, 2017
Amendment Flag	false
Current Fiscal Year End Date	--12-31
Entity Well-known Seasoned Issuer	Yes
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Filer Category	Large Accelerated Filer
Entity Public Float			$ 2,969.6
Entity Common Stock, Shares Outstanding		773,028,469
Document Fiscal Year Focus	2,017
Document Fiscal Period Focus	FY

CONSOLIDATED STATEMENTS OF EARN

CONSOLIDATED STATEMENTS OF EARNINGS - USD ($) shares in Millions, $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
CONSOLIDATED STATEMENTS OF EARNINGS
Net sales (including sales to related parties, see Note 16)	$ 6,654.5	$ 5,379.8	$ 5,045.9
Operating costs and expenses:
Cost of sales (exclusive of depreciation, amortization and depletion shown separately below)	3,252.8	3,034.1	2,927.6
Selling, general and administrative	93.1	94.3	99.4
Depreciation, amortization and depletion	671.1	647.1	510.7
Exploration	28.8	40.1	48.8
Environmental remediation	(10.2)		45
Total operating costs and expenses	4,035.6	3,815.6	3,631.5
Operating income	2,618.9	1,564.2	1,414.4
Interest expense	(357.4)	(360.3)	(334)
Capitalized interest	51.4	69.6	123.2
Other (expense)	(15.7)	(24.6)	(25.3)
Interest income	5.5	7.1	10.9
Income before income taxes	2,302.7	1,256	1,189.2
Current income taxes and royalty taxes	951.7	623.6	620.3
Deferred income taxes	641.7	(122.5)	(155.4)
Net income before equity earnings of affiliate	709.3	754.9	724.3
Equity earnings of affiliate, net of income tax	23.1	23.9	16.8
Net income	732.4	778.8	741.1
Less: Net income attributable to the non-controlling interest	3.9	2.3	4.7
Net income attributable to SCC	$ 728.5	$ 776.5	$ 736.4
Per common share amounts attributable to SCC:
Net earnings - basic and diluted	$ 0.94	$ 1	$ 0.93
Dividends declared and paid	$ 0.59	$ 0.18	$ 0.34
Weighted average common shares outstanding - basic and diluted	773	773.6	794.7

CONSOLIDATED STATEMENTS OF COMP

CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
COMPREHENSIVE INCOME:
Net income	$ 732.4	$ 778.8	$ 741.1
Other comprehensive income (loss) net of tax:
Decrease (increase) in pension and other post-retirement benefits (net of income tax of $(1.6), $2.6 and $2.6, respectively)	2.6	(3.5)	(3.7)
Foreign currency translation adjustments	0.3
Total other comprehensive income (loss)	2.9	(3.5)	(3.7)
Total comprehensive income	735.3	775.3	737.4
Comprehensive income attributable to the non-controlling interest	3.9	2.3	4.7
Comprehensive income attributable to SCC	$ 731.4	$ 773	$ 732.7

CONSOLIDATED STATEMENTS OF COM4

CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (Parenthetical) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME
(Increase) decrease in pension and other post-retirement benefits, income tax	$ (1.6)	$ 2.6	$ 2.6

CONSOLIDATED BALANCE SHEETS

CONSOLIDATED BALANCE SHEETS - USD ($) $ in Millions	Dec. 31, 2017	Dec. 31, 2016
Current assets:
Cash and cash equivalents	$ 1,004.8	$ 546
Restricted cash		3.6
Short-term investments	50.5	51.3
Accounts receivable trade	890.6	591.9
Accounts receivable other (including related parties 2017- $26.1 and 2016 - $23.4)	85.8	76.6
Inventories	1,041.9	1,010.4
Prepaid taxes	85.5	249.4
Other current assets	11	36.9
Total current assets	3,170.1	2,566.1
Property and mine development, net	9,099.6	8,766.5
Ore stockpiles on leach pads	977.4	806.9
Intangible assets, net	152.5	154.2
Deferred income tax	164.9	727.3
Equity method investment	99.7	87.5
Other non-current assets	115.9	125.8
Total assets	13,780.1	13,234.3
Current liabilities:
Accounts payable (including related parties 2017- $90.1 and 2016- $62.2)	659.8	584.2
Accrued income taxes	226.4	185.1
Accrued workers' participation	176.9	125.4
Accrued interest	83.9	85.6
Other accrued liabilities	21.3	18.7
Total current liabilities	1,168.3	999
Long-term debt	5,957.1	5,954.2
Deferred income taxes	38.5	162.6
Non current taxes payable	207.1
Other liabilities and reserves	37.2	31.1
Asset retirement obligation	222.5	216.5
Total non-current liabilities	6,462.4	6,364.4
Commitments and contingencies (Note 12)
STOCKHOLDERS' EQUITY (NOTE 13)
Common stock par value $0.01; shares authorized, 2017 and 2016 - 2,000; shares issued, 2017 and 2016 - 884.6	8.8	8.8
Additional paid-in capital	3,373.3	3,358.2
Retained earnings	5,726.2	5,455.3
Accumulated other comprehensive income	0.5	(2.4)
Treasury stock, at cost, common shares	(3,001.1)	(2,987.6)
Total Southern Copper Corporation stockholders' equity	6,107.7	5,832.3
Non-controlling interest	41.7	38.6
Total equity	6,149.4	5,870.9
Total liabilities and equity	$ 13,780.1	$ 13,234.3

CONSOLIDATED BALANCE SHEETS (Pa

CONSOLIDATED BALANCE SHEETS (Parenthetical) - USD ($) shares in Millions, $ in Millions	Dec. 31, 2017	Dec. 31, 2016
CONSOLIDATED BALANCE SHEETS
Accounts receivable other, related parties	$ 26.1	$ 23.4
Accounts payable, related parties	$ 90.1	$ 62.2
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, shares authorized	2,000	2,000
Common stock, shares issued	884.6	884.6

CONSOLIDATED STATEMENTS OF CASH

CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
OPERATING ACTIVITIES
Net income	$ 732.4	$ 778.8	$ 741.1
Adjustments to reconcile net earnings to net cash provided from operating activities:
Depreciation, amortization and depletion	671.1	647.1	510.7
Equity earnings of affiliate, net of dividends received	(12.3)	(11.3)	(9.4)
Loss (gain) on foreign currency transaction effect	24.9	(8.9)	(2.2)
Provision (benefit) for deferred income taxes	641.5	(117)	(153.2)
Other, net	8.9	28.2	2.6
Change in operating assets and liabilities:
(Increase) decrease in accounts receivable	(298.7)	(143.3)	91.6
(Increase) decrease in inventories	(201.9)	(207.9)	(260.3)
Increase (decrease) in accounts payable and accrued liabilities	139.5	30.5	(28.9)
(Increase) decrease in other operating assets and liabilities	271.2	(73.1)	(12.2)
Net cash provided by operating activities	1,976.6	923.1	879.8
INVESTING ACTIVITIES
Capital expenditures	(1,023.5)	(1,118.5)	(1,149.6)
Payments to acquire business, net of cash acquired			(100.4)
Purchase of short-term investments	(61.3)	(129.8)	(956.9)
Proceeds on sale of short-term investment	62.3	681.9	692.1
Loan repaid by related parties		111.2	50
Other, net	3.5	3.2	3.8
Net cash used in investing activities	(1,019)	(452)	(1,461)
FINANCING ACTIVITIES
Proceeds from issuance of debt			2,045.8
Repayments of debt			(266)
Payments of debt issuance cost			(11.8)
Repurchase of common shares		(71.7)	(1,004.4)
Cash dividends paid to common stockholders	(456.1)	(139.3)	(271.2)
Distributions to non-controlling interest	(0.3)		(0.5)
Other, net	0.3	0.3	0.3
Net cash (used in) provided by financing activities	(456.1)	(210.7)	492.2
Effect of exchange rate changes on cash and cash equivalents	(42.7)	11.1	(0.5)
Increase (decrease) in cash and cash equivalents	458.8	271.5	(89.5)
Cash and cash equivalents, at beginning of year	546	274.5	364
Cash and cash equivalents, at end of year	1,004.8	546	274.5
Cash paid during the year for:
Interest	356.7	356.7	315.8
Income taxes	889.8	571.8	737.7
Workers' participation	136	121.6	192.5
Supplemental schedule of non-cash operating, investing and financing activities:
Decrease (increase) in pension and other post-retirement benefits	2.9	(3.5)	(3.7)
Capital expenditures incurred but not yet paid	$ 137.7	$ 99.4	51
Fair value of assets acquired			128.3
Cash paid for the capital stock			(100)
Liabilities assumed			28.3
Stingray
Supplemental schedule of non-cash operating, investing and financing activities:
Purchase consideration			$ 100

CONSOLIDATED STATEMENTS OF CHAN

CONSOLIDATED STATEMENTS OF CHANGES IN EQUITY - USD ($) $ in Millions	Southern copper common sharesTREASURY STOCK:	Parent Company (Grupo Mexico) common sharesTREASURY STOCK:	CAPITAL STOCK:	ADDITIONAL PAID-IN CAPITAL:	TREASURY STOCK:	RETAINED EARNINGS:	ACCUMULATED OTHER COMPREHENSIVE INCOME (LOSS):	STOCKHOLDERS' EQUITY	NON-CONTROLLING INTEREST	Total
Balance at Dec. 31, 2014	$ (1,693.5)	$ (207.1)	$ 8.8	$ 3,344.7		$ 4,346.8	$ 4.8	$ 5,804.5	$ 32.1	$ 5,836.6
Increase (Decrease) in Stockholders' Equity
Share repurchase program	(1,004.4)									(1,004.4)
Used for corporate purposes	0.3
Other activity, including dividend, interest and foreign currency transaction effect		(4.2)
Other comprehensive (loss) income							(3.7)			737.4
Net earnings						736.4			4.7	736.4
Dividends/distributions declared and paid						(271.1)			(0.5)
Other activity of the period				5.1
Balance at Dec. 31, 2015	(2,697.6)	(211.3)	8.8	3,349.8	$ (2,908.9)	4,812.1	1.1	5,262.9	36.3	5,299.2
Increase (Decrease) in Stockholders' Equity
Share repurchase program	(71.7)									(71.7)
Used for corporate purposes	0.3
Other activity, including dividend, interest and foreign currency transaction effect		(7.3)
Other comprehensive (loss) income							(3.5)			775.3
Net earnings						776.5			2.3	776.5
Dividends/distributions declared and paid						(139.3)
Other activity of the period				8.4		6
Balance at Dec. 31, 2016	(2,769)	(218.6)	$ 8.8	3,358.2	(2,987.6)	5,455.3	(2.4)	5,832.3	38.6	5,870.9
Increase (Decrease) in Stockholders' Equity
Used for corporate purposes	0.3
Other activity, including dividend, interest and foreign currency transaction effect		(13.8)
Other comprehensive (loss) income							2.9			735.3
Net earnings						728.5			3.9	728.5
Dividends/distributions declared and paid						(456.1)			(0.8)
Other activity of the period				15.1		(1.5)
Balance at Dec. 31, 2017	$ (2,768.7)	$ (232.4)		$ 3,373.3	$ (3,001.1)	$ 5,726.2	$ 0.5	$ 6,107.7	$ 41.7	$ 6,149.4

CONSOLIDATED STATEMENTS OF CHA9

CONSOLIDATED STATEMENTS OF CHANGES IN EQUITY (Parenthetical) - $ / shares	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Dividends paid as cash dividend (in dollars per share)	$ 0.59	$ 0.18	$ 0.34
RETAINED EARNINGS:
Dividends paid as cash dividend (in dollars per share)	$ 0.59	$ 0.18	$ 0.34

DESCRIPTION OF THE BUSINESS_

DESCRIPTION OF THE BUSINESS:	12 Months Ended
	Dec. 31, 2017
DESCRIPTION OF THE BUSINESS:
DESCRIPTION OF THE BUSINESS:	NOTE 1—DESCRIPTION OF THE BUSINESS: The Company is a majority-owned, indirect subsidiary of Grupo Mexico S.A.B. de C.V. ("Grupo Mexico"). At December 31, 2017, Grupo Mexico through its wholly-owned subsidiary Americas Mining Corporation ("AMC") owned 88.9% of the Company's capital stock. The consolidated financial statements presented herein consist of the accounts of Southern Copper Corporation ("SCC" or the "Company"), a Delaware corporation, and its subsidiaries. The Company is an integrated producer of copper and other minerals, and operates mining, smelting and refining facilities in Peru and Mexico. The Company conducts its primary operations in Peru through a registered branch (the "Peruvian Branch" or "Branch" or "SPCC Peru Branch"). The Peruvian Branch is not a corporation separate from the Company. The Company's Mexican operations are conducted through subsidiaries. The Company also conducts exploration activities in Argentina, Chile, Ecuador, Mexico and Peru.

SUMMARY OF SIGNIFICANT ACCOUNTI

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES:	12 Months Ended
	Dec. 31, 2017
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES:
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES:	NOTE 2—SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES: Principles of consolidation— The consolidated financial statements include the accounts of subsidiaries of which the Company has voting control, in accordance with Accounting Standards Codification ("ASC") 810 Consolidation . Such financial statements are prepared in accordance with accounting principles generally accepted in the United States ("U.S. GAAP"). Use of estimates— The preparation of financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities, and disclosure of contingent assets and liabilities at the date of the financial statements, and the reported amounts of revenues and expenses during the reporting period. Significant items subject to such estimates and assumptions include the carrying value of ore reserves that are the basis for future cash flow estimates and amortization calculations; environmental reclamation, closure and retirement obligations; estimates of recoverable copper in mill and leach stockpiles; asset impairments (including estimates of future cash flows); unrecognized tax benefits; valuation allowances for deferred tax assets; and fair value of financial instruments. Management bases its estimates on the Company's historical experience and on various other assumptions that are believed to be reasonable under the circumstances. Actual results could differ from those estimates. Revenue recognition— Substantially all of the Company's copper and non-copper products are sold under annual or other longer-term contracts. Revenue is recognized when title passes to the customer. The passing of title is based on terms of the contract, generally upon shipment. Copper and non-copper revenues are determined based on the monthly average of prevailing commodity prices according to the terms of the contracts. The Company provides allowances for doubtful accounts based upon historical bad debt and claims experience and periodic evaluation of specific customer accounts. For certain of the Company's sales of copper and molybdenum products, customer contracts allow for pricing based on a month subsequent to shipping, in most cases within the following three months and occasionally in some cases a few additional months. In such cases, revenue is recorded at a provisional price at the time of shipment. The provisionally priced copper sales are adjusted to reflect forward LME or COMEX copper prices at the end of each month until a final adjustment is made to the price of the shipments upon settlement with customers pursuant to the terms of the contract. In the case of molybdenum sales, for which there are no published forward prices, the provisionally priced sales are adjusted to reflect the market prices at the end of each month until a final adjustment is made to the price of the shipments upon settlement with customers pursuant to the terms of the contract. These provisional pricing arrangements are accounted for separately from the contract as an embedded derivative instrument under ASC 815-30 "Derivatives and Hedging—Cash Flow Hedges." The Company sells copper in concentrate, anode, blister and refined form at industry standard commercial terms. Net sales include the invoiced value of copper, zinc, silver, molybdenum, sulfuric acid and other metals and the corresponding fair value adjustment of the related forward contract of copper and molybdenum. Shipping and handling fees and costs— Amounts billed to customers for shipping and handling are classified as sales. Amounts incurred for shipping and handling are included in cost of sales (exclusive of depreciation, amortization and depletion). Cash and cash equivalents— Cash and cash equivalents include bank deposits, certificates of deposit and short-term investment funds with original maturities of three months or less at the date of purchase. The carrying value of cash and cash equivalents approximates fair value. Short-term investments— The Company accounts for short-term investments in accordance with ASC 320-10 "Investments Debt and Equity Securities—Recognition." The Company determines the appropriate classification of all short-term investments as held-to-maturity, available-for-sale or trading at the time of purchase and re-evaluates such classifications as of each balance sheet date. Unrealized gains and losses on available-for-sale investments, net of taxes, are reported as a component of accumulated other comprehensive income (loss) in stockholders' equity, unless such loss is deemed to be other than temporary. Inventories— The Company principally produces copper and, in the production process, obtains several by-products, including molybdenum, silver, zinc, sulfuric acid and other metals. Metal inventories, consisting of work-in-process and finished goods, are carried at the lower of average cost or market. Costs of work-in-process inventories and finished goods mainly include power, labor, fuel, operating and repair materials, depreciation, amortization, depletion, and other necessary costs related to the extraction and processing of ore, including mining, milling, concentrating, smelting, refining, leaching and chemical processing. Costs incurred in the production of metal inventories exclude general and administrative costs. Once molybdenum, silver, zinc and other by-products are identified, they are transferred to their respective production facilities and the incremental cost required to complete production is assigned to their inventory value. Work-in-process inventories represent materials that are in the process of being converted into a saleable product. Conversion processes vary depending on the nature of the copper ore and the specific mining operation. For sulfide ores, processing includes milling and concentrating and results in the production of copper and molybdenum concentrates. Finished goods include saleable products (e.g., copper concentrates, copper anodes, copper cathodes, copper rod, molybdenum concentrate and other metallurgical products). Supplies inventories are carried at the lower of average cost or market. Long-term inventory—Ore stockpiles on leach pads. The leaching process is an integral part of the mining operations carried out at the Company's open-pit mines. The Company capitalizes the production cost of leachable material at its Toquepala, La Caridad and Buenavista mines recognizing it as inventory. This cost includes mining and haulage costs incurred to deliver ore to leach pads, depreciation, amortization, depletion and site overhead costs. The estimates of recoverable mineral content contained in the leaching dumps are supported by engineering studies. As the production cycle of the leaching process is significantly longer than the conventional process of concentrating, smelting and electrolytic refining, the Company includes on its balance sheet current leach inventory (included in work-in-process inventories) and long-term leach inventory. Amortization of leachable material is recorded by the units of production method. Property— Property is recorded at acquisition cost, net of accumulated depreciation and amortization. Cost includes major expenditures for improvements and replacements, which extend useful lives or increase capacity and interest costs associated with significant capital additions. Maintenance, repairs, normal development costs at existing mines and gains or losses on assets retired or sold are reflected in earnings as incurred. Buildings and equipment are depreciated on the straight-line method over estimated lives from five to 40 years or the estimated life of the mine if shorter. Mine development— Mine development includes primarily the cost of acquiring land rights to an exploitable ore body, pre-production stripping costs at new mines that are commercially exploitable, costs associated with bringing new mineral properties into production, and removal of overburden to prepare unique and identifiable areas outside the current mining area for such future production. Mine development costs are amortized on a unit of production basis over the remaining life of the mines. There is a diversity of practices in the mining industry in the treatment of drilling and other related costs to delineate new ore reserves. The Company follows the practices outlined in the next two paragraphs in its treatment of drilling and related costs. Drilling and other associated costs incurred in the Company's efforts to delineate new resources, whether near-mine or Greenfield are expensed as incurred. These costs are classified as mineral exploration costs. Once the Company determines through feasibility studies that proven and probable reserves exist and that the drilling and other associated costs embody a probable future benefit that involves a capacity, singly or in combination with other assets, to contribute directly or indirectly to future net cash inflow, then the costs are classified as mine development costs. These mine development costs incurred prospectively to develop the property are capitalized as incurred, until the commencement of production, and are amortized using the units of production method over estimated life of the ore body. During the production stage, drilling and other related costs incurred to maintain production are included in production cost in the period in which they are incurred. Drilling and other related costs incurred in the Company's efforts to delineate a major expansion of reserves at an existing production property are expensed as incurred. Once the Company determines through feasibility studies that proven and probable incremental reserves exist and that the drilling and other associated costs embody a probable future benefit that involves a capacity, singly or in combination with other assets, to contribute directly or indirectly to future net cash inflow, then the costs are classified as mine development costs. These incremental mine development costs are capitalized as incurred, until the commencement of production and amortized using the units of production method over the estimated life of the ore body. A major expansion of reserves is one that increases total reserves at a property by approximately 10% or more. For the years ended December 31, 2017, 2016 and 2015, the Company did not capitalize any drilling and related costs. Asset retirement obligations (reclamation and remediation costs)— The fair value of a liability for asset retirement obligations is recognized in the period in which the liability is incurred. The liability is measured at fair value and is adjusted to its present value in subsequent periods as accretion expense is recorded. The corresponding asset retirement costs are capitalized as part of the carrying value of the related long-lived assets and depreciated over the asset's useful life. Intangible assets— Intangible assets include primarily the excess amount paid over the book value for investment shares which are presented as mining concessions, and mining and engineering development studies. Intangible assets are carried at acquisition costs, net of accumulated amortization and are amortized principally on a unit of production basis over the estimated remaining life of the mines. Intangible assets are reviewed for impairment whenever events or changes in circumstances indicate that the carrying amount of the asset may not be recoverable. Debt issuance costs— Debt issuance costs related to a recognized debt liability are presented in the balance sheet as a direct deduction from the carrying amount of that debt liability, consistent with the treatment of a debt discount. Ore reserves— The Company periodically reevaluates estimates of its ore reserves, which represent the Company's estimate as to the amount of unmined copper remaining in its existing mine locations that can be produced and sold at a profit. Such estimates are based on engineering evaluations derived from samples of drill holes and other openings, combined with assumptions about copper market prices and production costs at each of the respective mines. The Company updates its estimate of ore reserves at the beginning of each year. In this calculation, the Company uses current metal prices which are defined as the average metal price over the preceding three years. The current price per pound of copper, as defined, was $2.50, $2.61 and $2.99 at the end of 2017, 2016 and 2015, respectively. The ore reserve estimates are used to determine the amortization of mine development and intangible assets. Once the Company determines through feasibility studies that proven and probable reserves exist and that the drilling and other associated costs embody a probable future benefit that involves a capacity, singly or in combination with other assets, to contribute directly or indirectly to future net cash inflow, then the costs are classified as mine development costs and the Company discloses the related ore reserves. Exploration— Tangible and intangible costs incurred in the search for mineral properties are charged against earnings when incurred. Income taxes— Provisions for income taxes are based on taxes payable or refundable for the current year and deferred taxes on temporary differences between the amount of taxable income and pretax financial income and between the tax bases of assets and liabilities and their reported amounts in the financial statements. Deferred tax assets and liabilities are included in the financial statements at currently enacted income tax rates applicable to the period in which the deferred tax assets and liabilities are expected to be realized and settled as prescribed in ASC 740 "Income taxes." As changes in tax laws or rates are enacted, deferred tax assets and liabilities are adjusted through the provision for income taxes. Deferred income tax assets are reduced by any benefits that, in the opinion of management, are more likely not to be realized. The Company's operations involve dealing with uncertainties and judgments in the application of complex tax regulations in multiple jurisdictions. The final taxes paid are dependent upon many factors, including negotiations with taxing authorities in various jurisdictions and resolution of disputes arising from federal, state, and international tax audits. The Company recognizes potential liabilities and records tax liabilities for anticipated tax audit issues in the U.S. and other tax jurisdictions based on its estimate of whether, and the extent to which, additional taxes will be due. The Company follows the guidance of ASC 740 "Income taxes" to record these liabilities. (See Note 7 "Income taxes" of the consolidated financial statements for additional information). The Company adjusts these reserves in light of changing facts and circumstances; however, due to the complexity of some of these uncertainties, the ultimate resolution may result in a payment that is materially different from the Company's current estimate of the tax liabilities. If its estimate of tax liabilities proves to be less than the ultimate assessment, an additional charge to expense would result. If payment of these amounts ultimately proves to be less than the recorded amounts, the reversal of the liabilities would result in tax benefits being recognized in the period when the Company determines the liabilities are no longer necessary. The Company classifies income tax-related interest and penalties as income taxes in the financial statements, as well as interest and penalties, if any, related to unrecognized tax benefits. On December 22, 2017, the U.S. government enacted the "Tax Cuts and Jobs Act" (the "Act"). The Act contains numerous provisions, the following of which most significantly impact the Company: (i) a decrease in the corporate tax rate from 35% to 21%; (ii) a transition of the U.S. taxation of international operation from a worldwide system to a quasi-territorial system and a one-time transition tax on the mandatory deemed repatriation of cumulative foreign earnings as of December 31, 2017, (iii) generally eliminates U.S. federal income taxes on dividends from foreign subsidiaries, requiring a current inclusion in U.S. federal taxable income of certain earnings of controlled foreign corporations and (iv) limitations on the use of foreign tax credits to reduce the U.S. income tax liability. The U.S. Securities and Exchange Commission ("SEC") issued Staff Accounting Bulletin No. 118 ("SAB 118"), which provides guidance on accounting for the tax effects of the Act. The Company has adopted SAB 118. Accordingly, the provisions of the Act deemed most relevant to the Company have been considered in preparation of its financial statements as of December 31, 2017 based on the Company's best estimate. See further disclosure regarding the impacts of the Act and the adoption of SAB 118 in Note 7 to the accompanying consolidated financial statements. Foreign exchange— The Company's functional currency is the U.S. dollar. As required by local law, both the Peruvian Branch and Minera Mexico maintain their books of accounts in Peruvian soles and Mexican pesos, respectively. Foreign currency assets and liabilities are remeasured into U.S. dollars at current exchange rates, except for non-monetary items such as inventory, property, intangible assets and other assets which are remeasured at historical exchange rates. Revenues and expenses are generally translated at actual exchange rates in effect during the period, except for those items related to balance sheet amounts that are remeasured at historical exchange rates. Gains and losses from foreign currency remeasurement are included in earnings of the period. Gains and (losses) resulting from foreign currency transactions are included in "Cost of sales (exclusive of depreciation, amortization and depletion)." Asset impairments— The Company evaluates long-term assets when events or changes in economic circumstances indicate that the carrying amount of such assets may not be recoverable. These evaluations are based on business plans that are prepared using a time horizon that is reflective of the Company's expectations of metal prices over its business cycle. The Company is currently using a long-term average copper price and an average molybdenum price for impairment tests, reflective of what the Company believes is the lower level of the current price environment. The results of its impairment tests using these long-term copper and molybdenum prices show no impairment in the carrying value of their assets. In recent years testing using assumptions for long-term average prices have resulted in stricter evaluation for impairment analysis than would the higher three year average prices for copper and molybdenum prices. Should this situation reverse in the future with three year average prices below the long-term price assumption, the Company would assess the need to use the three year average prices in its evaluations. The Company uses an estimate of the future undiscounted net cash flows of the related asset or asset group over the remaining life to measure whether the assets are recoverable and measures any impairment by reference to fair value. Other comprehensive income— Comprehensive income represents changes in equity during a period, except those resulting from investments by owners and distributions to owners. During the fiscal years ended December 31, 2017, 2016 and 2015, the components of "other comprehensive income (loss)" were, the unrecognized gain (loss) on employee benefit obligations and foreign currency translation adjustments. Business segments— Company management views Southern Copper as having three reportable segments and manages it on the basis of these segments. The segments identified by the Company are: 1) the Peruvian operations, which include the two open-pit copper mines in Peru and the plants and services supporting such mines, 2) the Mexican open-pit copper mines, which include La Caridad and Buenavista mine complexes and their supporting facilities and 3) the Mexican underground mining operations, which include five underground mines that produce zinc, lead, copper, silver and gold, a coal mine and a zinc refinery. Please see Note 17 "Segments and Related Information." Senior management of the Company focus on operating income as measure of performance to evaluate different segments, and to make decisions to allocate resources to the reported segments. This is a common measure in the mining industry. ADOPTION OF REVENUE RECOGNITION STANDARD In May 2014, the FASB issued ASU 2014-09 "Revenue from Contracts with Customers" (Topic 606). The objective of the new revenue standard is to provide a single comprehensive revenue recognition model for all contracts with customers to improve comparability within industries, across industries and across capital markets. The core principle of the standard is that the Company should recognize revenue to represent the transfer of promised goods or services to customers in an amount that reflects the consideration to which the Company expects to be entitled in exchange for those goods or services. The Company should apply the following five steps to achieve the core principle: Step 1: Identify the contract(s) with a customer. The guidance also specifies the accounting for some costs to obtain or fulfill a contract with a customer. Additionally, the Company should disclose sufficient qualitative and quantitative information to enable users of financial statements to understand the nature, amount, timing, and uncertainty of revenue and cash flows arising from contracts with customers. In March 2016, The FASB issued ASU 2016-08 Revenue from Contracts with Customers—(Topic 606) Principal versus Agent Considerations (Reporting Revenue Gross versus Net). This update clarifies the implementation guidance on principal versus agent considerations. When another party is involved in providing goods or services to a customer, an entity is required to determine whether the nature of its promise is to provide the specified good or service itself (that is, the entity is a principal) or to arrange for that good or service to be provided by the other party (that is, the entity is an agent). This revenue standard is effective for the first interim period within annual reporting periods beginning after December 15, 2017, and early adoption is not permitted. The Company has adopted the new guidance effective January 1, 2018, applying the modified retrospective approach. Under this approach, the results for reporting periods beginning after January 1, 2018 will be presented in the consolidated financial statements under the guidance, while prior period amounts will not be adjusted and will continue to be reported under the guidance in effect for those periods. Upon adoption by the Company, no cumulative effect adjustment is required to be recognized at January 1, 2018, as the adoption of the standard has not resulted in a change to the way the Company recognizes its revenue. The Company will apply the related disclosure requirements of the new standard beginning in 2018. OTHER NEW ACCOUNTING STANDARDS In January 2016, The FASB issued ASU 2016-01 "Financial instruments—Overall (Subtopic 825-10): Recognition and Measurement of Financial Assets and Financial Liabilities" which requires entities to measure equity investments that do not result in consolidation and are not accounted for under the equity method at fair value and to recognize any changes in fair value in net income. This update also includes certain disclosure requirements. This update is effective in fiscal years, including interim periods, beginning after December 15, 2017, and upon adoption, an entity should apply the amendments with the cumulative effect of initially applying the guidance recognized at January 1, 2018. Early adoption is not permitted. The Company has completed its assessment of the adoption of this standard and has determined that it will not have a material impact on its consolidated financial information. On February 25, 2016, the FASB issued ASU 2016-02 "Leases" (Topic 842). This Update significantly modifies the accounting model of leases for lessees; as it requires them to recognize assets and liabilities in the balance sheet for virtually all leases. However, the classification of leases as finance leases or operating leases is maintained for lessees. In addition, for leases with a term of 12 months or less, a lessee can elect by class of underlying asset not to record assets and liabilities on the balance sheet, and recognize lease expense on a straight-line basis over the lease term. The lessor accounting model for leases remains mostly unchanged from previous guidance, except for specific profit recognition requirements which were modified in order to align them to the new revenue recognition standard issued by the FASB, and the lease classification criteria, to ensure consistency with those for a lessee. The amendments in this Update are effective for public business entities for fiscal years, and interim periods within those fiscal years, beginning after December 15, 2018 and early adoption is permitted. The Company is evaluating the impact of the adoption of this new standard on the consolidated financial information. In June 2016, the FASB issued ASU 2016-13 "Financial Instruments—Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments" This ASU amends guidance on reporting credit losses for assets held at amortized cost basis and available for sale debt securities and requires a financial asset (or a group of financial assets) measured at amortized cost basis to be presented at the net amount expected to be collected. The allowance for credit losses is a valuation account that is deducted from the amortized cost basis of the financial asset(s) to present the net carrying value at the amount expected to be collected on the financial asset. For available for sale debt securities, credit losses should be measured in a manner similar to current GAAP, however Topic 326 will require that credit losses be presented as an allowance rather than as a write-down. This update is effective for fiscal years beginning after December 15, 2019, including interim periods within those fiscal years. The Company is evaluating the impact of the adoption of this new standard on the consolidated financial information. Other ASUs issued by the FASB that are pending adoption as of December 31, 2017 are not anticipated to have a significant impact on the Company's consolidated financial statements.

SHORT-TERM INVESTMENTS_

SHORT-TERM INVESTMENTS:	12 Months Ended
	Dec. 31, 2017
SHORT-TERM INVESTMENTS:
SHORT-TERM INVESTMENTS:	NOTE 3—SHORT-TERM INVESTMENTS: Short-term investments were as follows ($ in millions): At 2017 2016 Trading securities $ $ Weighted average interest rate % % Available-for-sale $ $ Weighted average interest rate % % ​ ​ ​ ​ ​ ​ ​ ​ Total $ $ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Trading securities consist of bonds issued by public companies and are publicly traded. Each financial instrument is independent of the others. The Company has the intention to sell these bonds in the short-term. Available-for-sale investments consist of securities issued by public companies. Each security is independent of the others and, as of December 31, 2017 and 2016, included corporate bonds and asset and mortgage backed obligations. As of December 31, 2017 and 2016, gross unrealized gains and losses on available-for-sale securities were not material. Related to these investments the Company earned interest, which was recorded as interest income in the consolidated statement of earnings. Also the Company redeemed some of these securities and recognized gains (losses) due to changes in fair value, which were recorded as other income (expense) in the consolidated statement of earnings. The following table summarizes the activity of these investments by category (in millions): Years ended 2017 2016 Trading: Interest earned $ $ Unrealized gain (loss) at December 31, $ $ Available-for-sale: Interest earned (* ) (* ) Investment redeemed $ $ (*) Less than $0.1 million At December 31, 2017 and 2016, contractual maturities of the available-for-sale debt securities are as follows (in millions): 2017 2016 One year or less $ — $ — Maturing after one year through five years — — Maturing after five years through ten years — — Due after 10 years ​ ​ ​ ​ ​ ​ ​ ​ Total debt securities $ $ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​

INVENTORIES_

INVENTORIES:	12 Months Ended
	Dec. 31, 2017
INVENTORIES:
INVENTORIES:	NOTE 4—INVENTORIES: At December 31, (in millions) 2017 2016 Inventory, current: Metals at average cost: Finished goods $ $ Work-in-process Ore stockpiles on leach pads Supplies at average cost ​ ​ ​ ​ ​ ​ ​ ​ Total current inventory $ $ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Inventory, long-term: Ore stockpiles on leach pads $ $ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Total leaching costs added as long-term inventory of ore stockpiles in leach pads amounted to $513.9 million, $439.0 million and $506.9 million in 2017, 2016 and 2015, respectively. Long-term leaching inventories recognized as cost of sales amounted to $333.5 million, $316.6 million and $274.1 million in 2017, 2016 and 2015, respectively.

PROPERTY_

PROPERTY:	12 Months Ended
	Dec. 31, 2017
PROPERTY:
PROPERTY:	NOTE 5—PROPERTY: At December 31, (in millions) 2017 2016 Buildings and equipment $ $ Construction in progress Mine development Mineral assets Land, other than mineral ​ ​ ​ ​ ​ ​ ​ ​ Total property Accumulated depreciation, amortization and depletion ) ) ​ ​ ​ ​ ​ ​ ​ ​ Total property and mine development, net $ $ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Construction in progress increased in 2017 as a result of the spending on the Company expansion projects. For more detailed information, please see Item 7 "Management Discussion and Analysis of Financial Condition and Results of Operations—Capital Investment Program." Depreciation and depletion expense for the years ended December 31, 2017, 2016 and 2015, amounted to $665.2 million, $639.1 million and $503.6 million, respectively.

INTANGIBLE ASSETS_

INTANGIBLE ASSETS:	12 Months Ended
	Dec. 31, 2017
INTANGIBLE ASSETS:
INTANGIBLE ASSETS:	NOTE 6—INTANGIBLE ASSETS: At December 31, (in millions) 2017 2016 Mining concessions $ $ Mine engineering and development studies Software ​ ​ ​ ​ ​ ​ ​ ​ Accumulated amortization: Mining concessions ) ) Mine engineering and development studies ) ) Software ) ) ​ ​ ​ ​ ​ ​ ​ ​ ) ) Goodwill ​ ​ ​ ​ ​ ​ ​ ​ Intangible assets, net $ $ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Amortization of intangibles for the years ended December 31, 2017, 2016 and 2015, amounted to $5.9 million, $8.0 million and $7.1 million, respectively. Estimated amortization are as follows: Estimated amortization expense (in millions): 2018 $ 2019 2020 2021 2022 ​ ​ ​ ​ ​ Total 2018 - 2022 $ ​ ​ ​ ​ ​ Average annual $ ​ ​ ​ ​ ​ Goodwill includes $17.0 million generated in 1997 as a result of purchasing a third party interest in the Buenavista mine. It also includes $24.9 million representing the amount of the purchase price in excess of the fair value of the net assets acquired from El Pilar mine. This goodwill is attributable to future benefits that the Company expects to realize from the mine and will not be deductible for income tax purposes.

INCOME TAXES_

INCOME TAXES:	12 Months Ended
	Dec. 31, 2017
INCOME TAXES:
INCOME TAXES:	NOTE 7—INCOME TAXES: Since March 2009, Grupo Mexico, through its wholly-owned subsidiary AMC, owns an interest in excess of 80% of SCC. Accordingly, SCC's results are included in the consolidated results of the Grupo Mexico subsidiary for U.S. federal income tax reporting. SCC provides current and deferred income taxes, as if it were filing a separate U.S. federal income tax return. On December 22, 2017, the Tax Cuts and Jobs Act (the "Act") was signed into law, making substantial changes to the 1986 Internal Revenue Code. Changes under the Act include, among others, a decrease in the corporate tax rate from 35% to 21%, the transition of the U.S. taxation of international operation from a worldwide system to a quasi-territorial system, a one-time transition tax on the mandatory deemed repatriation of cumulative foreign earnings as of December 31, 2017, a general elimination of U.S. federal income taxes on dividends from foreign subsidiaries, and a current inclusion in U.S. federal taxable income of certain earnings of controlled foreign corporations. Although most provisions of the Act begin January 1, 2018, ASC 740 "Income Taxes" requires that the effects of tax law changes be recognized in the year and period of the law change and be reflected in the company's financial results. On December 22, 2017, the SEC staff issued Staff Accounting Bulletin No. 118 ("SAB 118") to address the application of US GAAP in situations when a registrant does not have the necessary information available, prepared, or analyzed in reasonable detail to complete the accounting for certain income tax effects of the Act. SAB 118 requires a company to reflect the income tax effects of the Act for which the accounting under ASC 740 "Income Taxes" is complete; if it is incomplete but the Company is able to determine a reasonable estimate, a provisional estimate must be provided in the financial statements. If a provisional estimate cannot be reasonably prepared, the Company should continue to apply ASC 740 on the basis of the provision of the tax law that were in effect immediately before the enactment of the Act. Companies have one year from the enactment of the Act to finalize accounting for the impacts of the Act. The Company adopted SAB 118 and accordingly, its accounting for the effect of the Act is based on its best estimate, which may require adjustment in 2018. However, the Company was able to make reasonable estimates of certain effects and, therefore, recorded a provisional $785.9 million non-cash tax expense for the estimated effects of the Act. These adjustments were related to the valuation allowances for foreign tax credits and other deferred tax assets, valuation of our net deferred tax assets due to the rate change from 35% to 21% and the transition tax on the repatriation of cumulative foreign earnings . The ultimate impact of the Act may differ from these provisional amounts, possibly materially. After the Company files its 2017 U.S. federal income tax return and finalizes certain tax positions it will conclude whether further adjustments are required to its net deferred tax assets or liabilities, current year foreign tax credits and any liability associated with the one-time mandatory tax on the repatriation of foreign earnings. The Act also provides for two new taxes that become effective in tax years beginning after December 31, 2017: the Global Intangible Low Tax Income or GILTI tax and the Base Erosion Anti-Abuse or BEAT tax. The GILTI provisions impose a tax on foreign income in excess of a deemed return on tangible assets of foreign corporations. FASB guidance released in January 2018 indicates that either accounting for deferred taxes related to GILTI inclusions or treating any taxes on GILTI inclusions as period cost are both acceptable methods subject to an accounting policy election. Our selection of an accounting policy with respect to the new GILTI tax rules will depend, in part, on analyzing our global income to determine whether we expect to have future U.S. inclusions in taxable income related to GILTI and, if so, what the impact is expected to be. Because whether we expect to have future US inclusions in taxable income related to GILTI depends on not only our current structure and estimated future results of global operations but also our intent and ability to modify our structure and/or our business, we are not yet able to reasonably estimate the effect of this provision of the Tax Act. Therefore, we have not made any adjustments related to potential GILTI tax in our financial statements and have not made a policy decision regarding whether to record deferred taxes on GILTI. The BEAT tax is a 5% minimum tax for tax years beginning in 2018 (12.5% after 2025) and is calculated on a base equal to the Company's income determined without the tax benefit arising from base erosion payments. The erosion payments are a specifically defined set of deductible expenses. However, the provisions are unclear as to which payments should be characterized as base erosion payments. The tax reform prescribes that the Secretary issue Regulations to prevent the avoidance of the BEAT tax, which have still not been finalized. Additionally, the Company needs to evaluate any interaction between the GILTI and the BEAT taxes. Therefore, the Company is still is in the process of analyzing the provisions of these taxes and the effect they may or may not have on future results and financial reporting. Accordingly, for 2017, there is no change made to the accounting under ASC 740 and the Company is following current tax law with respect to these specific items. The components of the provision for income taxes for the three years ended December 31, 2017, are as follows: (in millions) 2017 2016 2015 U.S. federal and state: Current $ — $ — $ — Deferred ) ) Uncertain tax positions ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ) ) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Foreign (Peru and Mexico): Current Deferred ) ) ) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Total provision for income taxes $ $ $ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ The source of income is as follows: (in millions) 2017 2016 2015 Earnings by location: U.S. $ ) $ ) $ ) Foreign Peru ) Mexico ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Earnings before taxes on income $ $ $ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ The reconciliation of the statutory income tax rate to the effective tax rate for the three years ended December 31, 2017, is as follows (in percentage points): 2017 2016 2015 Expected tax at U.S. statutory rate % % % Foreign tax at other than statutory rate, net of foreign tax credit benefit(1) Percentage depletion ) ) ) Other permanent differences — Valuation allowance on US deferred tax assets, foreign tax credits and US tax effect on Peruvian deferred — — Decrease in US deferred tax asset due to tax rate changes — — US one time transition tax on accumulated foreign earnings — — Increase (decrease) in unrecognized tax benefits for uncertain tax positions Repatriated foreign earnings ) — Amounts (over) / under provided in prior years ) ) ) Other ) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Effective income tax rate % % % ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ (1) Foreign tax at other than statutory rates, net of foreign tax credit benefit, also includes the effects of permanent differences in Peru and Mexico, that are determined at the local statutory rate. The Company files income tax returns in three jurisdictions, Peru, Mexico and the United States. For the three years presented above, the statutory income tax rate for Mexico was 30% and 35% for the United States. The Peruvian tax rate was 29.5% for 2017 and 28% for 2016 and 2015. While the largest components of income taxes are the Peruvian and Mexican taxes, the Company is a domestic U.S. entity. Therefore, the rate used in the above reconciliation is the U.S. statutory rate. For all of the years presented, both the Peruvian branch and Minera Mexico filed separate tax returns in their respective tax jurisdictions. Although the tax rules and regulations imposed in the separate tax jurisdictions may vary significantly, similar permanent items exist, such as items which are nondeductible or nontaxable. Some permanent differences relate specifically to SCC such as the allowance in the United States for percentage depletion. Deferred taxes include the U.S., Peruvian and Mexican tax effects of the following types of temporary differences and carryforwards: At December 31, (in millions) 2017 2016 Assets: Inventories $ $ Capitalized exploration expenses U.S. foreign tax credit carryforward, net of FIN 48 liability U.S. tax effect of Peruvian deferred tax liability Property, plant and equipment — Reserves Mexican tax on consolidated dividends Prepaids — Valuation allowance on US deferred tax assets, foreign tax credits and US tax effect on Peruvian deferred ) — Other ​ ​ ​ ​ ​ ​ ​ ​ Total deferred tax assets ​ ​ ​ ​ ​ ​ ​ ​ Liabilities: Property, plant and equipment ) — Deferred charges ) ) Unremitted foreign earnings — ) Other ) ) ​ ​ ​ ​ ​ ​ ​ ​ Total deferred tax liabilities ) ) ​ ​ ​ ​ ​ ​ ​ ​ Total net deferred tax (liabilities) / assets $ ) $ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ U.S. Tax Matters— As of December 31, 2017, the Company considers its ownership of the stock of Minera Mexico to be essentially permanent in duration. The excess of the amount for financial reporting over the tax basis of the investment in this stock is estimated to be at least $6.7 billion. As of December 31, 2017, $517.7 million of the Company´s total cash, cash equivalents, restricted cash and short-term investments of $1,055.3 million was held by foreign subsidiaries. The cash, cash equivalents and short-term investments maintained in our foreign operations are generally used to cover local operating and investment expenses. At December 31, 2016, Minera Mexico determined that it had $470.5 million in earnings available for dividends to the United States. These earnings had not been remitted, but U.S. federal income tax, net of foreign tax credit was recognized in 2016 resulting in an increase tax of $45.7 million. At December 31, 2017, Minera Mexico had determined that it had earnings available for dividends to the United States of $555.5 million. The 2017 U.S. tax reform introduced a one-time transition tax that is based upon the Company's total accumulated post-1986 prescribed foreign earnings and profits ("E&P") estimated to be $8.9 billion, the majority of which was previously considered to be indefinitely reinvested and accordingly, no U.S. federal and state income taxes were provided. Upon enactment of the 2017 U.S. tax reform, the Company calculated and recorded a provisional tax amount of $181.1 million as a reasonable estimate for its one-time transition tax liability, which was completely offset by foreign tax credit carryforward utilization. Because of the complexities of tax reform and the transition tax calculation, the Company is still finalizing its calculation of the total accumulated post-1986 prescribed E&P for the applicable entities. Further, the transition tax is based in part on the amount of those earnings held in liquid and non-liquid E&P. Until the calculation of E&P is completed and the transition tax is finalized during 2018 it is not practicable to estimate any amount of unrecognized deferred tax liability, if any, to any additional outside basis differences in the Company's foreign subsidiaries. Earnings from the Company's Peruvian branch to the United States are not subject to transition taxes since they are taxed on a current basis, regardless of remittances. At December 31, 2017, there were $485.8 million of foreign tax credits available for carryback or carryforward. These credits have a one year carryback and a ten year carryforward period and can only be used to reduce U.S. income tax on foreign earnings. There were no other unused U.S. tax credits at December 31, 2017. These credits expire as follows: Year Amount 2022 2023 2024 2025 2026 ​ ​ ​ ​ ​ Total $ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ These foreign tax credits are presented above on a gross basis and have not been reduced here for any unrecognized tax benefits. These foreign tax credits have been adjusted to include the 2017 Net Operating Loss carryback in the U.S. jurisdiction, increasing foreign tax credits by approximately $15.9 million. In accordance with ASU 2013-11 the Company has recorded $205.7 million of an unrecognized tax benefit as an offset to the Company's deferred tax asset for foreign tax credits. The remaining foreign tax credits of $280.2 million are being re-valued to zero at December 31, 2017. It is the opinion of management that with the reduction in the U.S. corporate tax rate to 21% and the tax rates in Mexico and Peru at 30% and higher, it is unlikely the excess foreign tax credits can be utilized. Additionally, foreign dividends will no longer be taxed in the U.S. thereby reducing the U.S. tax on the foreign source income that the credits can be used to offset. Peruvian Tax Matters— Royalty mining charge: The royalty charge is based on operating income margins with graduated rates ranging from 1% to 12% of operating profits, with a minimum royalty charge assessed at 1% of net sales. If the operating income margin is 10% or less, the royalty charge is 1% and for each 5% increment in the operating income margin, the royalty charge rate increases by 0.75%, up to a maximum of 12%. The minimum royalty charge assessed at 1% of net sales is recorded as cost of sales and those amounts assessed against operating income are included in the income tax provision. The Company has accrued $23.4 million, $16.8 million and $22.9 million of royalty charges in 2017, 2016 and 2015, respectively, of which $2.5 million and $2.7 million were included in income taxes in 2017 and 2015, respectively; no amounts were included in income tax in 2016. Peruvian special mining tax: This tax is based on operating income with graduated rates increasing from 2% to 8.4%. The Company recognized $23.3 million, $10.8 million and $18.1 million in 2017, 2016 and 2015, respectively, with respect to this tax. These amounts are included as "income taxes" in the consolidated statement of earnings. In December 2016, the Peruvian Government enacted income tax law changes to both the income tax and dividend tax rate that become effective on January 1, 2017. The rates are as follows: Year Income Dividend 2015 - 2016 % % 2017 and later % % The recalculation of the deferred tax liability for the Peruvian jurisdiction using the new tax rates did not have a material effect on the deferred tax liability or the financial statements of the Company. Mexican Tax Matters— In 2013, the Mexican Congress enacted tax law changes that became effective on January 1, 2014. Among other effects, the amounts that the subsidiary companies of Minera Mexico recorded during 2017 were: • Mining royalty at the rate of 7.5% on taxable earnings before taxes: $87.8 million. • Additional royalty of 0.5% over gross income from sales of gold, silver and platinum: $0.8 million. • Income tax payable stemming from changes to tax consolidation: $0.3 million. On October 2017, the Federation's Revenue Law for 2018 was approved by the House of Representatives and the Senate. There are certain modifications that are worth highlighting: i) The incentive of crediting of the special use and service tax to income tax. In the case of fuel, it includes purchased diesel for final consumption in certain mining equipment. The crediting of the special use and service tax was extended to the purchase of imported diesel. ii) The Federal Revenue Law allows the deduction of statutory profit sharing paid, on advance monthly payments of income tax. iii) The withholding rate applied by banks and other members of the financial system on interest will decrease from an annual rate of 0.58% to 0.46%. iv) The obligation to provide certain information regarding relevant transactions will be incorporated to the Federation's Revenue Law for 2018 given the recent rulings issued by the Mexican Supreme Court. Taxpayers will be obligated to provide on a quarterly basis to the Mexican tax authorities information regarding financial derivative transactions, transactions with related parties, transactions related to the participation in the equity of other companies and changes of tax residence, corporate restructures and other similar transactions. It is worth noting that there are no further amendments in connection with the Base Erosion and Profit Shifting action plan. Accounting for Uncertainty in Income Taxes— The total amount of unrecognized tax benefits in 2017, 2016 and 2015, was as follows (in millions): 2017 2016 2015 Unrecognized tax benefits, opening balance $ $ $ Gross increases—tax positions in prior period ) Gross increases—current-period tax positions — Decreases related to settlements with taxing authorities — ) — ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ) ) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Unrecognized tax benefits, ending balance $ $ $ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ The amount of unrecognized tax benefits that, if recognized, would affect the effective tax rate was $214.5 million and $304.0 million at December 31, 2017 and 2016, respectively. These amounts relate entirely to U.S. income tax matters. The Company has no unrecognized Peruvian or Mexican tax benefits. The Company is currently under examination by the Internal Revenue Service for the years 2011-2013 as part of the audit of the AMC consolidated tax group. As of December 31, 2017 and December 31, 2016 the Company's liability for uncertain tax positions included accrued interest and penalties of $1.9 million. The following tax years remain open to examination and adjustment in the Company's three major tax jurisdictions: Peru: 2012 and all subsequent years U.S.: 2012 and all subsequent years Mexico: 2012 and all subsequent years Management does not expect that any of the open years will result in a cash payment within the upcoming twelve months ending December 31, 2018. The Company's reasonable expectations about future resolutions of uncertain items did not materially change during the year ended December 31, 2017.

WORKERS' PARTICIPATION_

WORKERS' PARTICIPATION:	12 Months Ended
	Dec. 31, 2017
WORKERS' PARTICIPATION:
WORKERS' PARTICIPATION:	NOTE 8—WORKERS' PARTICIPATION: The Company's operations in Peru and Mexico are subject to statutory workers' participation. In Peru, the provision for workers' participation is calculated at 8% of pre-tax earnings. The current portion of this participation, which is accrued during the year, is based on the Peruvian Branch's taxable income and is distributed to workers following determination of final results for the year. The annual amount payable to an individual worker is capped at the worker's salary for an 18 month period. Amounts determined in excess of the 18 months of worker's salary is no longer made as a payment to the worker and is levied first for the benefit of the "Fondo Nacional de Capacitacion Laboral y de Promocion del Empleo" (National Workers' Training and Employment Promotion Fund) until this entity receives from all employers in its region an amount equivalent to 2,200 Peruvian taxable units (approximately $2.7 million in 2017). Any remaining excess is levied as payment for the benefit of the regional governments. These levies fund worker training, employment promotion, entrepreneurship and various other programs. In Mexico, workers' participation is determined using the guidelines established in the Mexican income tax law at a rate of 10% of pre-tax earnings as adjusted by the tax law. The provision for workers' participation is allocated to "Cost of sales (exclusive of depreciation, amortization and depletion)" and to "selling, general and administrative" in the consolidated statement of earnings, proportional to the number of workers in the production and administrative areas, respectively. Workers' participation expense for the three years ended December 31, 2017 was as follows (in millions): 2017 2016 2015 Current $ $ $ Deferred ) ) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ $ $ $ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​

ASSET RETIREMENT OBLIGATION_

ASSET RETIREMENT OBLIGATION:	12 Months Ended
	Dec. 31, 2017
ASSET RETIREMENT OBLIGATION:
ASSET RETIREMENT OBLIGATION:	NOTE 9—ASSET RETIREMENT OBLIGATION: The Company maintains an estimated asset retirement obligation for its mining properties in Peru, as required by the Peruvian Mine Closure Law. In accordance with the requirements of this law, the Company's closure plans were approved by the Peruvian Ministry of Energy and Mines ("MINEM"). As part of the closure plans, the Company is required to provide annual guarantees over the estimated life of the mines, based on a present value approach, and to furnish the funds for the asset retirement obligation. This law requires a review of closing plans every five years. Currently and for the near-term future, the Company has pledged the value of its Lima office complex as support for this obligation. The accepted value of the Lima office building for this purpose is $36.9 million. Through January 2018, the Company has provided guarantees of $32.3 million. The closure cost recognized for this liability includes the cost, as outlined in its closure plans, of dismantling the Toquepala and Cuajone concentrators, the smelter and refinery in Ilo, and the shops and auxiliary facilities at the three units. In 2015, we added $12.5 million related to the Toquepala expansion closure plan. In 2017, according to Peruvian law requirements, the Cuajone mine closure plan was reviewed. As a result of this, an adjustment of $11.6 million was recorded. In 2010, the Company announced to the Mexican federal environmental authorities its closure plans for the copper smelter plant at San Luis Potosi. The Company initiated a program for plant demolition and soil remediation with a budget of $66.2 million, which has been spent through December 31, 2017. Plant demolition and construction of a confinement area at the south of the property were completed in 2012. In accordance with remediation goals previously approved by environmental authorities, soil remediation and on-site encapsulation on a second confinement area of impacted soils have been completed. Confirmation sampling was successfully completed. On September 2, 2016, the environmental authorities approved the conclusion of the remediation effort for San Luis Potosi. The Company continues studying the possibilities for this property in order to decide whether to sell or develop the property. The overall cost recognized for mining closure in Mexico includes the estimated costs of dismantling concentrators, smelter and refinery plants, shops and other facilities. In 2016, the Company added $9.5 million related to the Quebalix IV closure plan, a project that is part of the Buenavista expansion. The following table summarizes the asset retirement obligation activity for years ended December 31, 2017 and 2016 (in millions): 2017 2016 Balance as of January 1 $ $ Changes in estimates ) — Additions — Closure payments ) ) Accretion expense ​ ​ ​ ​ ​ ​ ​ ​ Balance as of December 31, $ $ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​

FINANCING_

FINANCING:	12 Months Ended
	Dec. 31, 2017
FINANCING:
FINANCING:	NOTE 10—FINANCING: Long-term debt (in millions): Face Issuance Issuance Carrying 5.375% Senior unsecured notes due 2020 $ $ ) $ ) $ 3.500% Senior unsecured notes due 2022 ) ) 3.875% Senior unsecured notes due 2025 ) ) 9.250% Yankee Bonds due 2028 — — 7.500% Senior unsecured notes due 2035 ) ) 6.750% Senior unsecured notes due 2040 ) ) 5.250% Senior unsecured notes due 2042 ) ) 5.875% Senior unsecured notes due 2045 ) ) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Total $ $ ) $ ) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Less, current portion — ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Total long-term debt $ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Face Issuance Issuance Carrying 5.375% Senior unsecured notes due 2020 $ $ ) $ ) $ 3.500% Senior unsecured notes due 2022 ) ) 3.875% Senior unsecured notes due 2025 ) ) 9.250% Yankee Bonds due 2028 — — 7.500% Senior unsecured notes due 2035 ) ) 6.750% Senior unsecured notes due 2040 ) ) 5.250% Senior unsecured notes due 2042 ) ) 5.875% Senior unsecured notes due 2045 ) ) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Total $ $ ) $ ) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Less, current portion — ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Total long-term debt $ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ The bonds, referred above as "Yankee bonds", contain a covenant requiring Minera Mexico to maintain a ratio of EBITDA to interest expense of not less than 2.5 to 1.0 as such terms are defined in the debt instrument. At December 31, 2017, Minera Mexico was in compliance with this covenant. Between July 2005 and November 2012 the Company issued senior unsecured notes six times totaling $4.2 billion, as listed above. Interest on the notes is paid semi-annually in arrears. The notes rank pari passu with each other and rank pari passu in right of payment with all of the Company's other existing and future unsecured and unsubordinated indebtedness. On April 20, 2015, the Company issued $2.0 billion of fixed-rate senior unsecured notes. This debt was issued in two tranches, $500 million due 2025 at an annual interest rate of 3.875% and $1.5 billion due 2045 at an annual interest rate of 5.875%. These notes are general unsecured obligations of the Company and rank equally with all of its existing and future unsecured and unsubordinated debt. Net proceeds are being used for general corporate purposes, including the financing of the Company´s capital investment program. The notes were issued with an underwriters' discount of $20.2 million. Additionally, issuance costs of $11.8 million associated with these notes were paid and deferred. The unamortized balance of the discount and the costs are presented net of the carrying value of the debt issued and are amortized as interest expense over the life of the loan. The indentures relating to the notes contain certain restrictive covenants, including limitations on liens, limitations on sale and leaseback transactions, rights of the holders of the notes upon the occurrence of a change of control triggering event, limitations on subsidiary indebtedness and limitations on consolidations, mergers, sales or conveyances. Certain of these covenants cease to be applicable before the notes mature if the Company obtains an investment grade rating. The Company obtained investment grade rating in 2005. The Company has registered these notes under the Securities Act of 1933, as amended. The Company may issue additional debt from time to time pursuant to certain of the indentures. If the Company experiences a "Change of Control Triggering Event", the Company must offer to repurchase the notes at a purchase price equal to 101% of the principal amount thereof, plus accrued and unpaid interest, if any. A Change of Control Trigger Event means a Change of Control (as defined) and a rating decline (as defined), that is, if the rating of the notes, by at least one of the rating agencies shall be decreased by one or more gradations. At December 31, 2017, the Company was in compliance with the covenants of the notes. Aggregate maturities of the outstanding borrowings at December 31, 2017, are as follows: Years Principal (in millions) 2018 $ — 2019 — 2020 2021 — 2022 Thereafter ​ ​ ​ ​ ​ Total $ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ (*) Total debt maturities do not include the debt discount valuation account of $94.1 million.

BENEFIT PLANS_

BENEFIT PLANS:	12 Months Ended
	Dec. 31, 2017
BENEFIT PLANS:
BENEFIT PLANS:	NOTE 11—BENEFIT PLANS: Post retirement defined benefit plans The Company has two noncontributory defined benefit pension plans covering former salaried employees in the United States and certain former expatriate employees in Peru (the "Expatriate Plan"). Effective October 31, 2000, the Board of Directors amended the qualified pension plan to suspend the accrual of benefits. In addition, the Company's Mexican subsidiaries have a defined contribution pension plan for salaried employees and a non-contributory defined benefit pension plan for union employees (the "Mexican Plan"). The components of net periodic benefit costs calculated in accordance with ASC 715 "Compensation retirement benefits," using December 31 as a measurement date, consist of the following: Years ended (in millions) 2017 2016 2015 Service cost $ $ $ Interest cost Expected return on plan assets ) ) ) Amortization of transition assets, net Amortization of net actuarial loss — — ) Settlement / Curtailment ) — Amortization of net loss/(gain) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Net periodic benefit cost $ ) $ ) $ ) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ The change in benefit obligation and plan assets and a reconciliation of funded status are as follows: As of (in millions) 2017 2016 Change in benefit obligation: Projected benefit obligation at beginning of year $ $ Service cost Interest cost Settlement ) Benefits paid ) ) Actuarial (gain)/loss ) Actuarial gain assumption changes ) Inflation adjustment ) ​ ​ ​ ​ ​ ​ ​ ​ Projected benefit obligation at end of year $ $ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Change in plan assets: Fair value of plan assets at beginning of year $ $ Actual return on plan assets Employer contributions ) ) Benefits paid ) ) Currency exchange rate adjustment ) ​ ​ ​ ​ ​ ​ ​ ​ Fair value of plan assets at end of year $ $ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Funded status at end of year: $ $ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ASC-715 amounts recognized in statement of financial position consists of: Non-current assets $ $ ​ ​ ​ ​ ​ ​ ​ ​ Total $ $ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ASC-715 amounts recognized in accumulated other comprehensive income (net of income taxes of $(2.0) million and $(3.3) million in 2017 and 2016, respectively) consists of: Net loss (gain) $ $ Prior service cost ​ ​ ​ ​ ​ ​ ​ ​ Total $ $ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ The following table summarizes the changes in accumulated other comprehensive income for the years ended December 31, related to the defined benefit pension plan, net of income tax: (in millions) 2017 2016 Reconciliation of accumulated other comprehensive income: Accumulated other comprehensive income at beginning of plan year $ $ Net loss/(gain) amortized during the year ) ) Net loss/(gain) occurring during the year ) Prior service cost (credit) — Currency exchange rate adjustment ) ​ ​ ​ ​ ​ ​ ​ ​ Net adjustment to accumulated other comprehensive income (net of income taxes of $1.3 million and $(3.3) million in 2017 and 2016, respectively) ) ​ ​ ​ ​ ​ ​ ​ ​ Accumulated other comprehensive income at end of plan year $ $ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ The following table summarizes the amounts in accumulated other comprehensive income amortized and recognized as a component of net periodic benefit cost in 2017 and 2016, net of income tax: (in millions) 2017 2016 Net loss / (gain) $ ) $ Amortization of net (loss) gain ) ) Amortization of prior services cost (credit) — ​ ​ ​ ​ ​ ​ ​ ​ Total amortization expenses $ ) $ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ The assumptions used to determine the pension obligations are: Expatriate Plan 2017 2016 2015 Discount rate % % % Expected long-term rate of return on plan asset % % % Rate of increase in future compensation level N/A N/A N/A Mexican Plan(*) 2017 2016 2015 Discount rate % % % Expected long-term rate of return on plan asset % % % Rate of increase in future compensation level % % % (*) These rates are based on Mexican pesos as pension obligations are denominated in pesos. The scheduled maturities of the benefits expected to be paid in each of the next five years, and thereafter, are as follows: Years Expected (in millions) 2018 $ 2019 2020 2021 2022 2023 to 2025 ​ ​ ​ ​ ​ Total $ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Expatriate Plan The Company's funding policy is to contribute amounts to the qualified plan sufficient to meet the minimum funding requirements set forth in the Employee Retirement Income Security Act of 1974 plus such additional amounts as the Company may determine to be appropriate. Plan assets are invested in a group annuity contract with Metropolitan Life Insurance Company ("MetLife"). The Contract invests in the MetLife General Account Payment Fund (the "Money Fund") and the MetLife Broad Market Core Bond Fund (the "Bond Fund") managed by BlackRock, Inc. The Money Fund seeks to earn interest and maintain a $1.00 per share net asset value, by investing in U.S. Dollar-denominated money market securities. The Bond Fund seeks to outperform the Bloomberg Barclays ® U.S. Aggregate Bond Index, net of fees, over a full market cycle. The Bond Fund invests in publicly traded, investment grade securities. These may include corporate securities, mortgage securities, treasuries and cash, agency securities, commercial mortgage backed securities and other investment vehicles adhering to the fund's investment objectives. These investments are classified as Level 1 because they are valued using quoted prices of the same securities as they consist of instruments which are publicly traded. Plan assets are invested with the objective of maximizing returns with an acceptable level of risk and maintaining adequate liquidity to fund expected benefit payments. The Company's policy for determining asset mix-targets to meet investment objectives includes periodic consultation with recognized third party investment consultants. The expected long-term rate of return on plan assets is reviewed annually, taking into consideration asset allocations, historical returns and the current economic environment. Based on these factors the Company expects its assets will earn an average of 4.00% per annum assuming its long-term mix will be consistent with its current mix. Mexican Plan Minera Mexico's policy for determining asset mix targets includes periodic consultation with recognized third party investment consultants. The expected long-term rate of return on plan assets is updated periodically, taking into consideration assets allocations, historical returns and the current economic environment. The fair value of plan assets is impacted by general market conditions. If actual returns on plan assets vary from the expected returns, actual results could differ. The plan assets are managed by three financial institutions, Scotiabank Inverlat S.A., Banco Santander and Banco Mercantil del Norte, S.A. 30% of the funds are invested in Mexican government securities, including treasury certificates and development bonds of the Mexican government. The remaining 70% is invested in common shares of Grupo Mexico. The plan assets are invested without restriction in active markets that are accessible when required and are therefore considered as level 1, in accordance with ASC 820 "Fair Value Measurement." These plans accounted for approximately 30% of benefit obligations. The following table represents the asset mix of the investment portfolio as of December 31: 2017 2016 Asset category: Equity securities % % Treasury bills % % ​ ​ ​ ​ ​ ​ ​ ​ % % ​ ​ ​ ​ ​ ​ ​ ​ The amount of contributions that the Company expects to pay to the plan during 2018 is $1.4 million, which excludes $3.4 million of pending payments to former Buenavista workers. Post-retirement Health Care Plan: United States: The Company adopted a post-retirement health care plan for retired salaried employees eligible for Medicare in 1996. The Company manages the plan and is currently providing health benefits to retirees. The plan is accounted for in accordance with ASC 715 "Compensation retirement benefits." In Mexico, health services are provided by the Mexican Social Security Institute. The components of net period benefit costs for the three years ended December 31, 2017 are as follows: Years ended (in millions) 2017 2016 2015 Interest cost $ $ $ Amortization of prior service cost/ (credit) ) ) ) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Net periodic benefit cost $ $ $ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ The change in benefit obligation and a reconciliation of funded status are as follows: As of (in millions) 2017 2016 Change in benefit obligation: Projected benefit obligation at beginning of year $ $ Interest cost Actuarial loss/ (gain)—claims cost ) — Benefits paid ) ) Actuarial (gain)/loss ) Inflation adjustment ) ​ ​ ​ ​ ​ ​ ​ ​ Projected benefit obligation at end of year $ $ ​ ​ ​ ​ ​ ​ ​ ​ Change in plan assets: Fair value of plan assets at beginning of year $ — $ — Employer contributions Benefits paid ) ) ​ ​ ​ ​ ​ ​ ​ ​ Fair value of plan assets at end of year $ — $ — ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Funded status at end of year: $ $ ) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ASC-715 amounts recognized in statement of financial position consists of: Current liabilities $ ) $ ) Non-current liabilities ) ) ​ ​ ​ ​ ​ ​ ​ ​ Total $ ) $ ) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ASC-715 amounts recognized in accumulated other comprehensive income consists of: Net loss (gain) $ ) $ ) Total (net of income taxes of $1.7 million and $1.4 million in 2017 and 2016, respectively) $ ) $ ) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ The following table summarizes the changes in accumulated other comprehensive income for the years ended December 31, related to the post-retirement health care plan, net of income tax: As of (in millions) 2017 2016 Reconciliation of accumulated other comprehensive income: Accumulated other comprehensive income at beginning of plan year $ ) $ ) Net loss/(gain) occurring during the year ) Net loss/(gain) amortized during the year Currency exchange rate adjustment ) ​ ​ ​ ​ ​ ​ ​ ​ Net adjustment to accumulated other comprehensive income (net of income taxes of $0.3 million and $1.9 million in 2017 and 2016, respectively) ) ​ ​ ​ ​ ​ ​ ​ ​ Accumulated other comprehensive income at end of plan year $ ) $ ) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ The following table summarizes the amounts in accumulated other comprehensive income amortized and recognized as a component of net periodic benefit cost in 2017 and 2016, net of income tax: At (in millions) 2017 2016 Net loss / (gain) $ ) $ Amortization of net (loss) gain ​ ​ ​ ​ ​ ​ ​ ​ Total amortization expenses $ ) $ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ The discount rates used in the calculation of other post-retirement benefits and cost as of December 31 were: 2017 2016 2015 Expatriate health plan Discount rate % % % Mexican health plan Weighted average discount rate % % % The benefits expected to be paid in each of the next five years, and thereafter, are as follows: Year Expected (in millions) 2018 $ 2019 2020 2021 2022 2023 to 2027 ​ ​ ​ ​ ​ Total $ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Expatriate Health Plan For measurement purposes for pre 65 year old participants, a 5.9% annual rate of increase in the per capita cost of covered health care benefits was assumed for 2017 which gradually decrease to 4.2% in a 85 year period. For post 65 year old the annual rate of increase in the per capita cost for 2017 is 6.3% which is assumed to decrease gradually to 4.6%. Assumed health care cost trend rates can have a significant effect on amounts reported for health care plans. However, because of the size of the Company's plan, a one percentage-point change in assumed health care trend rate would not have a significant effect. Mexican Health Plan For measurement purposes, a 4.5% annual rate of increase in the per capita cost of covered health care benefits was assumed for 2017 and remains at that level thereafter. An increase in other benefit cost trend rates have a significant effect on the amount of the reported obligations, as well as component cost of the other benefit plan. One percentage-point change in assumed other benefits cost trend rates would have the following effects: One Percentage (in millions) Increase Decrease Effect on total service and interest cost components $ $ Effect on the post-retirement benefit obligation $ $

COMMITMENTS AND CONTINGENCIES_

COMMITMENTS AND CONTINGENCIES:	12 Months Ended
	Dec. 31, 2017
COMMITMENTS AND CONTINGENCIES:
COMMITMENTS AND CONTINGENCIES:	NOTE 12—COMMITMENTS AND CONTINGENCIES: Environmental matters: The Company has instituted extensive environmental conservation programs at its mining facilities in Peru and Mexico. The Company's environmental programs include, among others, water recovery systems to conserve water and minimize the impact on nearby streams, reforestation programs to stabilize the surface of the tailings dams and the implementation of scrubbing technology in the mines to reduce dust emissions. Environmental capital investments in years 2017, 2016 and 2015, were as follows (in millions): 2017 2016 2015 Peruvian operations $ $ $ Mexican operations ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Total $ $ $ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Peruvian operations: The Company's operations are subject to applicable Peruvian environmental laws and regulations. The Peruvian government, through the Ministry of Environment ("MINAM") conducts annual audits of the Company's Peruvian mining and metallurgical operations. Through these environmental audits, matters related to environmental obligation, compliance with legal requirements, atmospheric emissions, effluent monitoring and waste management are reviewed. The Company believes that it is in material compliance with applicable Peruvian environmental laws and regulations. Peruvian law requires that companies in the mining industry provide assurances for future mine closure and remediation. In accordance with the requirements of this law, the Company's closure plans were approved by MINEM. See Note 9 "Asset retirement obligation," for further discussion of this matter. In accordance with the requirements of the law, in 2015 the Company submitted the closure plans for the Tia Maria project and for the Toquepala expansion. The process of review and approval of closure plans usually takes several months. In March 2016, MINEM approved the Mining Closure Plan for the Toquepala expansion project. The closure plan for the Tia Maria project was approved in February 2017. The Company, however, has not recorded a retirement obligation for the project as the construction permit has not been received, and work on the project is on hold. The Company believes that under these circumstances the recording of a retirement obligation is not appropriate. In December 2017, the Company submitted the mine closure plan update for the Cuajone operations, which is under review and evaluation by MINEM. In 2008, the Peruvian government enacted environmental regulations establishing stringent air quality standards ("AQS") for daily sulfur dioxide ("SO2") in the air for the Peruvian territory. These regulations, as amended in 2013, recognized distinct zones/areas, as atmospheric basins. MINAM had established three atmospheric basins that required further attention to comply with the air quality standards. The Ilo basin was one of these three areas and the Company's smelter and refinery are part of the area. In June 2017, MINAM enacted a supreme decree which defines new AQS for daily sulfur dioxide and gaseous mercury for the Peruvian territory, as well as monthly lead in particulate matter (PM10), in order to adopt standards similar to comparable countries and conform them to the technical capabilities available in Peru, while ensuring the protection of public health. This decree also considers criteria established by the World Health Organization and establishes a mean 24-hour AQS equal to 250 micrograms per cubic meter (µg/m3) of SO2 to replace the current 24-hour AQS of 20 µg/m3 of SO2, effective since 2014. The decree also establishes a mean 24-hour AQS equal to 2 µg/m3 of gaseous mercury and a mean monthly AQS equal to 1.5 µg/m3 of lead in PM10. The Company believes that these new AQS are appropriate for Peru and will allow Peruvian industry to be competitive with other countries. The Company has evaluated the potential impact of these new standards and expects that its adoption will not have a material impact on the financial position of the Company, as currently the Company maintains a lower daily average level of µg/m3 of SO2, than those required by the new AQS. In addition, in June 2017, MINAM enacted a supreme decree which establishes new quality standards for water in the Peruvian territory. The Company has reviewed this decree and considers that its adoption will not have a material impact on its financial position. In 2013, the Peruvian government enacted soil environmental quality standards ("SQS") applicable to any existing facility or project that generates or could generate the risk of soil contamination in its area of operation or influence. In March 2014, MINAM issued a supreme decree, which establishes additional provisions for the gradual implementation of SQS. Under this rule the Company had twelve months to identify contaminated sites in and around its facilities and present a report of identified contaminated sites. These documents were submitted to MINEM for approval in April 2015. After MINEM's review, the documents for the Company's operations were fully approved in July 2017. The next step is for the Company to prepare a characterization study to determine the depth, extent and physio-chemical composition of the contaminated areas and define an appropriate remediation plan with time-frame for completion. In addition, the Company must submit for approval a Soil Decontamination Plan (SDP) within 30 months after being notified by the authority. This SDP must include remediation actions, a schedule and compliance deadlines. Also under this rule, if deemed necessary and given reasonable justification, the Company may request a one year extension for the decontamination plan. Soil confirmation tests must be carried out after completion of decontamination actions (within the approved schedule) and results must be presented to authorities within 30 days after receiving such results. Non-compliance with this obligation or with decontamination goals will carry penalties, although no specific sanctions have been established yet. During compliance with this schedule, companies cannot be penalized for non-compliance with the SQS. While the Company believes that there is a reasonable possibility that a potential loss contingency may exist, it cannot currently estimate the amount of the contingency. The Company believes that a reasonable determination of the loss will be possible once the characterization study and the SDP are substantially completed, which is expected for the first quarter of 2020. At that time the Company will be in a position to estimate the remediation cost. Further, the Company does not believe that it can estimate a reasonable range of possible costs until the noted studies have substantially progressed and therefore is not be able to disclose a range of costs that is meaningful. Mexican operations : The Company's operations are subject to applicable Mexican federal, state and municipal environmental laws, to Mexican official standards, and to regulations for the protection of the environment, including regulations relating to water supply, water quality, air quality, noise levels and hazardous and solid waste. The principal legislation applicable to the Company's Mexican operations is the Federal General Law of Ecological Balance and Environmental Protection (the "General Law"), which is enforced by the Federal Bureau of Environmental Protection ("PROFEPA"). PROFEPA monitors compliance with environmental legislation and enforces Mexican environmental laws, regulations and official standards. It may also initiate administrative proceedings against companies that violate environmental laws, which in the most extreme cases may result in the temporary or permanent shutdown of non-complying facilities, the revocation of operating licenses and/or other sanctions or fines. In 2011, the General Law was amended, giving an individual or entity the ability to contest administrative acts, including environmental authorizations, permits or concessions granted, without the need to demonstrate the actual existence of harm to the environment as long as it can be argued that the harm may be caused. In addition, in 2011, amendments to the Civil Federal Procedures Code ("CFPC") were enacted. These amendments establish three categories of collective actions by means of which 30 or more people claiming injury derived from environmental, consumer protection, financial services and economic competition issues will be considered to be sufficient in order to have a legitimate interest to seek through a civil procedure restitution or economic compensation or suspension of the activities from which the alleged injury derived. The amendments to the CFPC may result in more litigation, with plaintiffs seeking remedies, including suspension of the activities alleged to cause harm. In 2013, the Environmental Liability Federal Law was enacted. The law establishes general guidelines for actions to be considered to likely cause environmental harm. If a possible determination regarding harm occurs, environmental clean-up and remedial actions sufficient to restore environment to a pre-existing condition should be taken. Under this law, if restoration is not possible, compensation measures should be provided. Criminal penalties and monetary fines can be imposed under this law. 2014 accidental spill at Buenavista mine: In 2014, an accidental spill of approximately 40,000 cubic meters of copper sulfate solution occurred at a Buenavista mine leaching pond. This solution reached the Bacanuchi River and the Sonora River. The Company took immediate actions to contain the spill, and to comply with all necessary legal requirements. The Company hired contractors including environmental specialists and assigned more than 1,200 of its own personnel to clean the river. In addition, the Company developed a service program to assist the residents of the Sonora River region. • Administrative proceedings: The National Water Commission, the Federal Commission for the Protection of Sanitary Risk and PROFEPA initiated administrative proceedings regarding the spill to determine possible environmental and health damages. On September 15, 2014, the Company executed an administrative agreement with PROFEPA, providing for the submission of a remediation action plan to the Mexican Ministry of Environment and Natural Resources (Secretaria de Medio Ambiente y Recursos Naturales "SEMARNAT"). The general remediation program submitted to SEMARNAT was approved on January 6, 2015. The Company also created a trust with a Mexican development bank, acting as a Trustee to support environmental remedial actions in connection with the spill, to comply with the remedial action plan and to compensate those persons adversely affected by the spill. The Company committed up to two billion Mexican pesos (approximately $150 million). A technical committee for the trust was created with representatives from the federal government, the Company and specialists assisted by a team of environmental experts to ensure the proper use of the funds. Along with the administrative agreement executed with PROFEPA, the trust served as an alternative mechanism for dispute resolution to mitigate public and private litigation risks. On December 1, 2016, SEMARNAT issued its final resolution which held that all remediation actions contained in the remediation plan, had been fulfilled and that all requirements had been complied with, except for biological monitoring activities at the Sonora River that will continue until the first semester of 2019 pursuant to the plan. On January 26, 2017, PROFEPA issued its final resolution under which it declared all mitigation actions completed and its investigation closed. In light of the above, the Company has obtained all necessary formal rulings from SEMARNAT and PROFEPA. On February 7, 2017, the Company closed the trust. As a result, $10.2 million of excess provision was credited to income in the first quarter of 2017. The total expense recorded for this accident in 2014 and 2015 was $136.4 million. Therefore, the remediation concerns raised by SEMARNAT and PROFEPA have been addressed. • Other procedures: On August 19, 2014, PROFEPA, as part of the administrative proceeding initiated after the spill, announced the filing of a criminal complaint against Buenavista del Cobre S.A. de C.V. ("BVC"), a subsidiary of the Company, in order to determine those responsible for the environmental damages. The Company is vigorously defending itself against this complaint. As of December 31, 2017, the case remains pending resolution. Through the first half of 2015, six collective action lawsuits were filed in federal courts in Mexico City and Sonora against two subsidiaries of the Company seeking economic compensation, clean up and remedial activities in order to restore the environment to its pre-existing conditions. Two of the collective action lawsuits have been dismissed by the court. The plaintiffs in the four remaining lawsuits are: Acciones Colectivas de Sinaloa, A.C. which established two collective actions, Defensa Colectiva A.C.; and Ana Luisa Salazar Medina et al. which has been granted a collective action certification. The remaining plaintiffs have requested cautionary measures on the construction of facilities for the monitoring of public health services and the prohibition of the closure of the Río Sonora Trust. As of December 31, 2017, these cases remain pending resolution. Similarly, during 2015, eight civil action lawsuits were filed against BVC in the state courts of Sonora seeking damages for alleged injuries and for moral damages as a consequence of the spill. The plaintiffs in the state court lawsuits are: Jose Vicente Arriola Nunez et al; Santana Ruiz Molina et al; Andres Nogales Romero et al; Teodoro Javier Robles et al; Gildardo Vasquez Carvajal et al; Rafael Noriega Souffle et al; Grupo Banamichi Unido de Sonora El Dorado, S.C. de R.L. de C.V; and Marcelino Mercado Cruz. In 2016, three additional civil action lawsuits, claiming similar damages, were filed by Juan Melquicedec Lebaron; Blanca Lidia Valenzuela Rivera et al and Ramona Franco Quijada et al. In 2017, BVC was served with thirty-three additional civil action lawsuits, claiming similar damages. The lawsuits were filed by Francisco Javier Molina Peralta et al; Anacleto Cohen Machini et al; Francisco Rafael Alvarez Ruiz et al; Jose Alberto Martinez Bracamonte et al; Gloria del Carmen Ramirez Duarte et al; Flor Margarita Sabori et al; Blanca Esthela Ruiz Toledo et al; Julio Alfonso Corral Domínguez et al; Maria Eduwiges Bracamonte Villa et al; Francisca Marquez Dominguez et al; Jose Juan Romo Bravo et al; Jose Alfredo Garcia Leyva et al; Gloria Irma Dominguez Perez et al; Maria del Refugio Romero et al; Miguel Rivas Medina et al; Yolanda Valenzuela Garrobo et al; Maria Elena Garcia Leyva et al; Manuel Alfonso Ortiz Valenzuela et al; Francisco Alberto Arvayo Romero et al; Maria del Carmen Villanueva Lopez et al; Manuel Martin Garcia Salazar; Miguel Garcia Arguelles et al; Dora Elena Rodriguez Ochoa et al; Honora Eduwiges Ortiz Rodriguez et al; Francisco Jose Martinez Lopez et al; Maria Eduwiges Lopez Bustamante; Rodolfo Barron Villa et al, Jose Carlos Martinez Fernandez et al, Maria de los Angeles Fabela et al; Rafaela Edith Haro et al; Luz Mercedes Cruz et al; Juan Pedro Montaño et al; and Juana Irma Alday Villa. As of December 31, 2017, these cases remain pending resolution. During 2015, four constitutional lawsuits (juicios de amparo) were filed before Federal Courts against various authorities and against a subsidiary of the Company, arguing; (i) the alleged lack of a waste management program approved by SEMARNAT; (ii) the alleged lack of a remediation plan approved by SEMARNAT with regard to the August 2014 spill; (iii) the alleged lack of community approval regarding the environmental impact authorizations granted by SEMARNAT to one subsidiary of the Company; and (iv) the alleged inactivity of the authorities with regard of the spill in August 2014. The plaintiffs of these lawsuits are: Francisca Garcia Enriquez, et al which established two lawsuits, Francisco Ramon Miranda, et al and Jesus David Lopez Peralta et al. During the third quarter of 2016, four additional constitutional lawsuits, claiming similar damages were filed by Mario Alberto Salcido et al; Maria Elena Heredia Bustamante et al; Martin Eligio Ortiz Gamez et al; and Maria de los Angeles Enriquez Bacame et al. During the third quarter of 2017, BVC was served with another constitutional lawsuit filed by Francisca García Enriquez et al. As of December 31, 2017, these cases remain pending resolution. It is not currently possible to determine the extent of the damages sought in these state and federal lawsuits but the Company considers that these lawsuits are without merit. Accordingly, the Company is vigorously defending against them. Nevertheless, the Company considers that none of the legal proceedings resulting from the spill, individually or in the aggregate, would have a material effect on its financial position or results of operations. The Company believes that all of its facilities in Peru and Mexico are in material compliance with applicable environmental, mining and other laws and regulations. The Company also believes that continued compliance with environmental laws of Mexico and Peru will not have a material adverse effect on the Company's business, properties, result of operations, financial condition or prospects and will not result in material capital investments. Litigation matters : The "Virgen Maria" Mining Concessions of the Tia Maria Mining Project The Tia Maria project includes various mining concessions, totaling 32,989.64 hectares. One of the concessions is the "Virgen Maria" mining concession totaling 943.72 hectares or 2.9% of the total mining concessions. Related to the "Virgen Maria" mining concessions, in August 2009, a lawsuit was filed against SCC's Branch by the former stockholders of Exploraciones de Concesiones Metalicas S.A.C. ("Excomet"). The plaintiffs allege that the acquisition of Excomet's shares by the Branch is null and void because the $2 million purchase price paid by the Branch for the shares of Excomet was not fairly negotiated by the plaintiffs and the Branch. In 2005, the Branch acquired the shares of Excomet after lengthy negotiations with the plaintiffs, and after the plaintiffs, which were all the stockholders of Excomet, approved the transaction in a general stockholders' meeting. Excomet was at the time owner of the "Virgen Maria" mining concession. In October 2011, the civil court dismissed the case on the grounds that the claim had been barred by the statute of limitations. On appeal by the plaintiffs, the Superior Court reversed the lower court's decision and remanded it to the lower court for further proceedings. In August 2015, the lower court dismissed the case on the grounds that the plaintiffs had not proven the alleged unfairness of the negotiations. The plaintiffs appealed this resolution before the Superior Court. In September 2016, the Superior Court confirmed the lower court's resolution and the plaintiffs filed an extraordinary appeal in order to have the case reviewed by the Supreme Court. In June 2017, the Supreme Court dismissed the extraordinary appeal filed by the plaintiffs. Therefore, the lawsuit ended favorably for the Company. The Tia Maria Mining Project There are four lawsuits filed against the Peruvian Branch of the Company related to the Tia Maria project. The lawsuits seek (i) to declare null and void the resolution which approved the Environmental Impact Assessment of the project; (ii) the cancellation of the project and the withdrawal of mining activities in the area and (iii) to declare null and void the mining concession application of the Tia Maria project. The lawsuits were filed by Messrs. Jorge Isaac del Carpio Lazo (filed May 22, 2015), Ernesto Mendoza Padilla (filed May 26, 2015), Juan Alberto Guillen Lopez (filed June 18, 2015) and Nicolas Belfiore Nicolini (filed November 13, 2015). The del Carpio Lazio case was rejected by the court of first instance on November 14, 2016. The plaintiff filed an appeal before the Superior Court on January 3, 2017. On January 9, 2018, the lawyers of both parties presented their respective positions before the Appellate Court. As of February 20, 2018, the case remains pending resolution. The Mendoza Padilla case was rejected by the lower court on July 8, 2015. This ruling was confirmed by the Superior Court on June 14, 2016. On July 12, 2016, the case was appealed before the Constitutional Court. As of December 31, 2017, the case remains pending resolution without further developments. The Guillen Lopez case is currently before the lower court. As of December 31, 2017, the case remains pending resolution without further developments. In the Belfiore Nicolini case, the court ruled partially in favor of the plaintiff. However, the Company filed an appeal to challenge said decision. As of February 20, 2018, the file was sent to the Appelllate Court for reviewing. The Company asserts that these lawsuits are without merit and is vigorously defending against them. The potential contingency amount for these cases cannot be reasonably estimated by management at this time. Special Regional Pasto Grande Project ("Pasto Grande Project") In 2012, the Pasto Grande Project, an entity of the Regional Government of Moquegua, filed a lawsuit against SCC's Peruvian Branch alleging property rights over a certain area used by the Peruvian Branch and seeking the demolition of the tailings dam where SCC's Peruvian Branch has deposited its tailings from the Toquepala and Cuajone operations since 1995. The Peruvian Branch has had title to use the area in question since 1960 and has constructed and operated the tailing dams with proper governmental authorization, since 1995. Upon a motion filed by the Peruvian Branch, the lower court has included MINEM as a defendant in this lawsuit. MINEM has answered the complaint and denied the validity of the claim. As of December 31, 2017, the case remains pending resolution without further developments. SCC's Peruvian Branch asserts that the lawsuit is without merit and is vigorously defending against it. The amount of this contingency cannot be reasonably estimated by management at this time. Carla Lacey and Barbara Siegfried, on behalf of themselves and all other similarly situated stockholders of Southern Copper Corporation, and derivatively on behalf of Southern Copper Corporation A purported class action derivative lawsuit filed in the Delaware Court of Chancery was served on the Company and its Directors in February 2016 relating to the 2012 capitalization of 99.999% of MGE by Controladora de Infraestructura Energetica Mexico, S.A. de C.V., an indirect subsidiary of Grupo Mexico (the "CIEM Capitalization"), the Company's entry into a power purchase agreement with MGE in 2012 (the "MGE Power Purchase Agreement"), and the 2012 restructuring of a loan from the Company's Mexican Operations to MGE for the construction of two power plants to supply power to the Company's Mexican operations (the "MGE Loan Restructuring"). The action purports to be brought on behalf of the Company and its common stockholders. The complaint alleges, among other things, that the CIEM Capitalization, the MGE Power Purchase Agreement and the MGE Loan Restructuring were the result of breaches of fiduciary duties and the Company's charter. The Company has filed a response denying these allegations and is currently in the discovery process. Labor matters : Peruvian operations: 69% of the Company's 4,628 Peruvian employees were unionized at December, 2017. Currently, there are six separate unions, one large union and five smaller unions. In the first quarter of 2016, the Company signed three-year agreements with five unions. These agreements include, among other things, annual salary increases of 5% for each of the three years. In April 2017, the Unified Labor Union of SPCC workers and one of Toquepala's unions began a strike, demanding a review of certain health and profit sharing benefits. The strike ended after 12 days. These two unions began illegal strikes in July and November 2017, that lasted five days and 21 days, respectively. The Company estimates that the loss of copper production resulting from the 2017 strikes was not significant and its sales contracts were not affected. Mexican operations : In recent years, the Mexican operations have experienced a positive improvement of their labor environment, as its workers opted to change their affiliation from the Sindicato Nacional de Trabajadores Mineros, Metalurgicos y Similares de la Republica Mexicana (the "National Mining Union") to other less politicized unions. However, the workers of the San Martin and Taxco mines, are still under the National Mining Union and have been on strike since July 2007. On December 10, 2009, a federal court confirmed the legality of the San Martin strike. In order to recover the control of the San Martin mine and resume operations, the Company filed a court petition on January 27, 2011 requesting that the court, among other things, define the termination payment for each unionized worker. The court denied the petition alleging that, according to federal labor law, the union was the only legitimate party to file such petition. On appeal by the Company, on May 13, 2011, the Mexican federal tribunal accepted the petition. In July 2011, the National Mining Union appealed the favorable court decision before the Supreme Court. On November 7, 2012, the Supreme Court affirmed the decision of the federal tribunal. The Company filed a new proceeding before the labor court on the basis of the Supreme Court decision, which recognized the right of the labor court to define responsibility for the strike and the termination payment for each unionized worker. A favorable decision of the labor court in this new proceeding would have the effect of terminating the protracted strike at San Martin. As of December 31, 2017, the case remains pending resolution without further developments. In the case of the Taxco mine, following the workers refusal to allow exploration of new reserves, the Company commenced litigation seeking to terminate the labor relationship with workers at the mine (including termination of the related collective bargaining agreement). On September 1, 2010, the federal labor court issued a ruling approving the termination of the collective bargaining agreement and all the individual labor contracts of the workers affiliated with the Mexican mining union at the Taxco mine. The mining union appealed the labor court ruling before a federal court. In September 2011, the federal court accepted the union's appeal and remanded the case to the federal labor court for reconsideration. After several legal proceedings on January 25, 2013, the Company filed a new proceeding before the labor court. On June 16, 2014, the labor court denied the petition of the Company. The resolution issued by the labor court was challenged by the Company before a federal court. In August 2015, the Supreme Court decided to assert jurisdiction over the case and to rule on it directly. As of December 31, 2017, the case remains pending resolution without further developments. It is expected that operations at these mines will remain suspended until these labor issues are resolved. In view of these lengthy strikes, the Company has reviewed the carrying value of the San Martin and Taxco mines to ascertain whether impairment exists. The Company concluded that there is a non-material impairment of the assets located at these mines. Other legal matters : The Company is involved in various other legal proceedings incidental to its operations, but does not believe that decisions adverse to it in any such proceedings, individually or in the aggregate, would have a material effect on its financial position or results of operations. Other commitments : Peruvian Operations Tia Maria: On August 1, 2014, the Company received the final approval of Tia Maria´s Environmental Impact Assessment ("EIA"). However, the issuance of the project´s construction permit has been delayed due to pressures from anti-mining groups. The Company continues working with community groups in order to resolve open issues concerning the project. The Company is also working jointly with the Peruvian Government to obtain the construction license for this 120,000 tons of SX-EW copper per year greenfield project. The Company expects the license to be issued in the first half of 2018. Tia Maria´s project budget is approximately $1.4 billion, of which $353.9 million has been invested through December 31, 2017. When completed, it is expected to produce 120,000 tons of copper cathodes per year. This project will use state-of-the-art SX-EW technology with the highest international environmental standards. SX-EW facilities are the most environmentally friendly in the industry as they do not require a smelting process and consequently, no emissions are released into the atmosphere. The project will only use seawater, transporting this more than 25 kilometers to 1,000 meters above sea level, and includes a desalinization plant which will be constructed at a cost of $95 million. Consequently, the Tambo river water resources and the water resources from the wells in the area will be used solely for farming and human consumption. The Company expects the project to generate 3,500 jobs during the construction phase. When in operation, Tia Maria will directly employ 600 workers and indirectly provide jobs to another 2,000. Through its expected twenty-year life, the project related services will create significant business opportunities in the Arequipa region. In view of the delay in this project, the Company continues to review the carrying value of this asset to ascertain whether impairment exists. Should the Tia Maria project not move forward, the Company is confident that most of the project equipment will continue to be used productively, through reassignment to other mine locations operated by the Company. The Company believes that an impairment loss, if any, will not be material. Toquepala Concentrator Expansion: In April 2015, the construction permit for the Toquepala expansion project was approved by the MINEM. The project budget is $1.2 billion, of which $892.9 million has been expended through December 31, 2017. When completed, this expansion project is expected to increase annual production capacity by 100,000 tons of copper and 3,100 tons of molybdenum. The project has reached 87% progress and is expected to be completed by the third quarter of 2018. Corporate Social Responsibility: The Company has a corporate social responsibility policy to maintain and promote continuity of its mining operations and obtain the best results. The main objective of this policy is to integrate its operations with the local communities in the areas of influence of its operations by creating a permanent positive relationship with them, in order to develop the optimum social conditions and to promote sustainable development in the area. Accordingly, the Company has made the following commitments: Tacna Region : In connection with the Toquepala concentrator expansion, the Company has committed to fund various social and infrastructure improvement projects in Toquepala's neighboring communities. The total amount committed for these purposes is S/ 445.0 million (approximately $132 million). Moquegua Region : In the Moquegua region, the Company is part of a "development roundtable" in which the local municipal authorities, the community representatives and the Company discuss the social needs and the way the Company could contribute to sustainable development in the region. As part of this, the roundtable is discussing the creation of a Moquegua Region Development Fund for which the Company has offered a contribution of S/ 700 million (approximately $209 million). While final funding is not yet settled, the Company has committed to contribute S/ 108.5 million (approximately $32 million) in advance, which is being utilized in an educational project and S/ 48.4 million (approximately $14 million) for a residual water treatment plant in Ilo, a sea-wall embankment and a fresh water facility at El Algarrobal. In addition, the Company has committed S/ 143.0 million (approximately $43 million) for the construction of five infrastructure projects in the Moquegua region under the "social investment for taxes" (obras por impuestos) program which allows the Compan

STOCKHOLDERS' EQUITY

STOCKHOLDERS' EQUITY	12 Months Ended
	Dec. 31, 2017
STOCKHOLDERS' EQUITY:
STOCKHOLDERS' EQUITY:	NOTE 13—STOCKHOLDERS' EQUITY Treasury Stock: Activity in treasury stock in the years 2017 and 2016 was as follows (in millions): 2017 2016 Southern Copper common shares Balance as of January 1, $ $ Purchase of shares — Used for corporate purposes ) ) ​ ​ ​ ​ ​ ​ ​ ​ Balance as of December 31, ​ ​ ​ ​ ​ ​ ​ ​ Parent Company (Grupo Mexico) common shares Balance as of January 1, Other activity, including dividend, interest and foreign currency transaction effect ​ ​ ​ ​ ​ ​ ​ ​ Balance as of December 31, ​ ​ ​ ​ ​ ​ ​ ​ Treasury stock balance as of December 31, $ $ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ SCC shares of common stock in treasury: At December 31, 2017 and 2016, treasury stock holds 111,567,617 shares and 111,579,617 shares of SCC's common stock with a cost of $2,768.7 million and $2,769.0 million, respectively. The shares of SCC's common stock held in treasury are used for Director's stock award plans and available for general corporate purposes. SCC share repurchase program: In 2008, the Company's Board of Directors ("BOD") authorized a $500 million share repurchase program that has since been increased by the BOD and is currently authorized to $3 billion. Pursuant to this program, the Company purchased common stock as shown in the table below. These shares are available for general corporate purposes. The Company may purchase additional shares of its common stock from time to time, based on market conditions and other factors. This repurchase program has no expiration date and may be modified or discontinued at any time. Maximum Period Total Number of Total Number Average Total Cost From To 2008 2012 $ 2013: 2014: 2015: 2016: Total purchased $ $ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ (1) NYSE closing price of SCC common shares at December 31, 2017. There has not been any activity in the SCC share repurchase program since the third quarter of 2016. As a result of the repurchase of shares of SCC's common stock, Grupo Mexico's direct and indirect ownership was 88.9% as of December 31, 2017 and 2016. Directors' Stock Award Plan: The Company established a stock award compensation plan for certain directors who are not compensated as employees of the Company. Under this plan, participants will receive 1,200 shares of common stock upon election and 1,200 additional shares following each annual meeting of stockholders thereafter. 600,000 shares of Southern Copper common stock have been reserved for this plan. The Company's Board of Directors and the stockholders approved a one-year extension of the Plan until January 29, 2018. The fair value of the award is measured each year at the date of the grant. In 2017 and 2016 the stock based compensation expense under this plan equaled $0.4 million and $0.3 million, respectively. The plan expired by its terms on January 29, 2018. A 5-year extension of the plan is being submitted for approval by the Company's stockholders at the 2018 Annual Meeting of Stockholders. The activity of this plan for the years ended December 31, 2017 and 2016 was as follows: 2017 2016 Total SCC shares reserved for the plan ​ ​ ​ ​ ​ ​ ​ ​ Total shares granted at January 1, ) ) Granted in the period ) ) ​ ​ ​ ​ ​ ​ ​ ​ Total shares granted at December 31, ) ) ​ ​ ​ ​ ​ ​ ​ ​ Remaining shares reserved ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Parent Company common shares: At December 31, 2017 and 2016, there were in treasury 108,450,672 and 115,667,784 of Grupo Mexico's common shares, respectively. Employee Stock Purchase Plan: 2010 Plan: During 2010, the Company offered to eligible employees a stock purchase plan through a trust that acquires series B shares of Grupo Mexico stock for sale to its employees, employees of subsidiaries, and certain affiliated companies. The purchase price was established at 26.51 Mexican pesos (approximately $1.28) for the initial subscription. Every two years employees were able to acquire title to 50% of the shares paid in the previous two years. The employees paid for shares purchased through monthly payroll deductions over the eight year period of the plan. At the end of the eight year period, the Company granted the participant a bonus of one share for every ten shares purchased by the employee. The participants were entitled to receive dividends in cash for dividends paid by Grupo Mexico for all shares that were fully purchased and paid by the employee as of the date that the dividend is paid. If the participant had only partially paid for shares, the entitled dividends were used to reduce the remaining liability owed for purchased shares. In the case of voluntary or involuntary resignation/termination of the employee, the Company paid to the employee the fair market sales price at the date of resignation/termination of the fully paid shares, net of costs and taxes. When the fair market sales value of the shares was higher than the purchase price, the Company applied a deduction over the amount to be paid to the employee based on a decreasing schedule specified in the plan. In case of retirement or death of the employee, the Company rendered the buyer or his legal beneficiary, the fair market sales value as of the date of retirement or death of the shares effectively paid, net of costs and taxes. The stock based compensation expense for the years ended December 31, 2017, 2016 and 2015 and the remaining balance of the unrecognized compensation expense under this plan were as follows (in millions): 2017 2016 2015 Stock based compensation expense $ $ $ Unrecognized compensation expense $ $ $ The plan ended in January 29, 2018. The following table presents the stock award activity of the 2010 Employee Stock Purchase Plan for the years ended December 31, 2017 and 2016: Shares Unit Weighted Average Outstanding shares at January 1, 2017 $ Granted — — Exercised ) Forfeited — — ​ ​ ​ ​ ​ ​ ​ ​ Outstanding shares at December 31, 2017 $ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Outstanding shares at January 1, 2016 $ Granted — — Exercised ) Forfeited — — ​ ​ ​ ​ ​ ​ ​ ​ Outstanding shares at December 31, 2016 $ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 2015 Plan : In January 2015, the Company offered to eligible employees a new stock purchase plan (the "New Employee Stock Purchase Plan") through a trust that acquires series B of shares of Grupo Mexico stock for sale to its employees, and employees of subsidiaries, and certain affiliated companies. The purchase price was established at 38.44 Mexican pesos (approximately $1.86) for the initial subscription, which expires on January 2023. Every two years employees will be able to acquire title to 50% of the shares paid in the previous two years. The employees will pay for shares purchased through monthly payroll deductions over the eight year period of the plan. At the end of the eight year period, the Company will grant the participant a bonus of 1 share for every 10 shares purchased by the employee. Any future subscription will be at the average market price at the date of acquisition or the grant date. If Grupo Mexico pays dividends on shares during the eight year period, the participants will be entitled to receive the dividend in cash for all shares that have been fully purchased and paid as of the date that the dividend is paid. If the participant has only partially paid for shares, the entitled dividends will be used to reduce the remaining liability owed for purchased shares. In the case of voluntary or involuntary resignation/termination of the employee, the Company will pay to the employee the fair market sales price at the date of resignation of the fully paid shares, net of costs and taxes. When the fair market sales value of the shares is higher than the purchase price, the Company will apply a deduction over the amount to be paid to the employee based on a decreasing schedule specified in the plan. In case of retirement or death of the employee, the Company will render the buyer or his legal beneficiary, the fair market sales value as of the date of retirement or death of the shares effectively paid, net of costs and taxes. The stock based compensation expense for the years ended December 31, 2017, 2016 and 2015 and the unrecognized compensation expense under this plan were as follows (in millions): 2017 2016 2015 Stock based compensation expense $ $ $ Unrecognized compensation expense $ $ $ The following table presents the stock award activity of this plan for the years ended December 31, 2017 and 2016: Shares Unit Weighted Average Outstanding shares at January 1, 2017 $ Granted — Exercised ) $ Forfeited — ​ ​ ​ ​ ​ ​ ​ ​ Outstanding shares at December 31, 2017 $ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Outstanding shares at January 1, 2016 $ Granted — — Exercised ) $ Forfeited — — ​ ​ ​ ​ ​ ​ ​ ​ Outstanding shares at December 31, 2016 $ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Executive Stock Purchase Plan: Grupo Mexico also offers a stock purchase plan for certain members of its executive management and the executive management of its subsidiaries and certain affiliated companies. Under this plan, participants will receive incentive cash bonuses which are used to purchase shares of Grupo Mexico which are deposited in a trust. Non-controlling interest: For all the years presented, in the consolidated statement of earnings the income attributable to non-controlling interest is based on the earnings of the Company's Peruvian Branch. The non-controlling interest of the Company's Peruvian Branch is for investment shares. These shares were generated by legislation in place in Peru from the 1970s through 1991; such legislation provided for the participation of mining workers in the profits of the enterprises for which they worked. This participation was divided between equity and cash. The investment shares included in the non-controlling interest on the consolidated balance sheets are the still outstanding equity distributions made to the Peruvian Branch's employees. In prior years, the Company acquired some Peruvian investment shares in exchange for newly issued common shares of the Company and through purchases at market value. These acquisitions were accounted for as purchases of non-controlling interests. The excess paid over the carrying value was assigned to intangible assets and is being amortized based on production. As a result of these acquisitions, the remaining investment shareholders hold a 0.71% interest in the Peruvian Branch and are entitled to a pro rata participation in the cash distributions made by the Peruvian Branch. The shares are recorded as a non-controlling interest in the Company's financial statements.

FAIR VALUE MEASUREMENT_

FAIR VALUE MEASUREMENT:	12 Months Ended
	Dec. 31, 2017
FAIR VALUE MEASUREMENT:
FAIR VALUE MEASUREMENT:	NOTE 14—FAIR VALUE MEASUREMENT: Subtopic 820-10 of ASC "Fair value measurement and disclosures—Overall" establishes a fair value hierarchy that prioritizes the inputs to valuation techniques used to measure fair value. The hierarchy gives the highest priority to unadjusted quoted prices in active markets for identical assets or liabilities (Level 1 measurements) and the lowest priority to unobservable inputs (Level 3 measurements). The three levels of the fair value hierarchy under Subtopic 820-10 are described below: Level 1—Unadjusted quoted prices in active markets that are accessible at the measurement date for identical, unrestricted assets or liabilities. Level 2—Inputs that are observable, either directly or indirectly, but do not qualify as Level 1 inputs. (i.e., quoted prices for similar assets or liabilities). Level 3—Prices or valuation techniques that require inputs that are both significant to the fair value measurement and unobservable (i.e., supported by little or no market activity). The carrying amounts of certain financial instruments, including cash and cash equivalents, accounts receivable (other than accounts receivable associated with provisionally priced sales) and accounts payable approximate fair value due to their short maturities. Consequently, such financial instruments are not included in the following table that provides information about the carrying amounts and estimated fair values of other financial instruments that are not measured at fair value in the consolidated balance sheet as of December 31, 2017 and December 31, 2016 (in millions): At December 31, 2017 At December 31, 2016 Carrying Value Fair Value Carrying Value Fair Value Liabilities: Long-term debt level 1 Long-term debt level 2 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Total long-term debt $ $ $ $ Long-term debt is carried at amortized cost and its estimated fair value is based on quoted market prices classified as Level 1 in the fair value hierarchy except for the cases of the Yankee bonds (in 2016 and 2017), the notes due 2020 and the notes due 2022 (in 2017), which qualify as Level 2 in the fair value hierarchy as they are based on quoted priced in market that are not active. Fair values of assets and liabilities measured at fair value on a recurring basis were calculated as of December 31, 2017 and 2016, as follows (in millions): Fair Value at Measurement Date Using: Description Fair Value Quoted prices in Significant Significant Assets: Short term investment: —Trading securities $ $ — $ — —Available-for-sale debt securities: Corporate bonds — $ — Asset backed securities — — Mortgage backed securities — — Accounts receivable: —Embedded derivatives—Not classified as hedges: Provisionally priced sales: Copper — — Molybdenum — — ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Total $ $ $ $ — ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Fair Value at Measurement Date Using: Description Fair Value Quoted prices in Significant Significant Assets: Short term investment: —Trading securities $ $ — $ — —Available-for-sale debt securities: Corporate bonds — — — — Asset backed securities — — — — Mortgage backed securities — $ — Accounts receivable: —Embedded derivatives—Not classified as hedges: Provisionally priced sales: Copper — — Molybdenum — — ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Total $ $ $ $ — ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ The Company's short-term trading securities investments are classified as Level 1 because they are valued using quoted prices of the same securities as they consist of bonds issued by public companies and publicly traded. The Company's short-term available-for-sale investments are classified as Level 2 because they are valued using quoted prices for similar investments. The Company's accounts receivables associated with provisionally priced copper sales are valued using quoted market prices based on the forward price on the LME or on the COMEX. Such value is classified within Level 1 of the fair value hierarchy. Molybdenum prices are established by reference to the publication Platt's Metals Week and are considered Level 1 in the fair value hierarchy.

CONCENTRATION OF RISK_

CONCENTRATION OF RISK:	12 Months Ended
	Dec. 31, 2017
CONCENTRATION OF RISK:
CONCENTRATION OF RISK:	NOTE 15—CONCENTRATION OF RISK: The Company operates four open-pit copper mines, five underground poly-metallic mines, two smelters and eight refineries in Peru and Mexico and substantially all of its assets are located in these countries. There can be no assurances that the Company's operations and assets that are subject to the jurisdiction of the governments of Peru and Mexico will not be adversely affected by future actions of such governments. Much of the Company's products are exported from Peru and Mexico to customers principally in the United States, Europe, Asia and South America. Financial instruments, which potentially subject the Company to a concentration of credit risk, consist primarily of cash and cash equivalents, short-term investments and trade accounts receivable.The Company invests or maintains available cash with various banks, principally in the United States, Mexico, Europe and Peru, or in commercial papers of highly-rated companies. As part of its cash management process, the Company regularly monitors the relative credit standing of these institutions. At December 31, 2017, SCC had invested its cash and cash equivalents and short-term investments as follows: % in one institution Country $ in % of total of country of total cash United States $ % % % Switzerland % % % Peru % % % Mexico % % % ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Total cash and short-term investment $ % ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ (1) 94.9% of the Company's cash is in U.S. dollars. During the normal course of business, the Company provides credit to its customers. Although the receivables resulting from these transactions are not collateralized, the Company has not experienced significant problems with the collection of receivables. The Company is exposed to credit loss in cases where the financial institutions with which it has entered into derivative transactions (commodity, foreign exchange and currency/interest rate swaps) are unable to pay when they owe funds as a result of protection agreements with them. To minimize the risk of such losses, the Company only uses highly-rated financial institutions that meet certain requirements. The Company also periodically reviews the creditworthiness of these institutions to ensure that they are maintaining their ratings. The Company does not anticipate that any of the financial institutions will default on their obligations. The Company's largest customers as percentage of accounts receivable and total sales were as follows: 2017 2016 2015 Accounts receivable trade as of December 31, Five largest customers % % % Largest customer % % % Total sales in year Five largest customers % % % Largest customer % % %

RELATED PARTY TRANSACTIONS_

RELATED PARTY TRANSACTIONS:	12 Months Ended
	Dec. 31, 2017
RELATED PARTY TRANSACTIONS:
RELATED PARTY TRANSACTIONS:	NOTE 16—RELATED PARTY TRANSACTIONS: The Company has entered into certain transactions in the ordinary course of business with parties that are controlling shareholders or their affiliates. These transactions include the lease of office space, air transportation, construction services and products and services related to mining and refining. The Company lends and borrows funds among affiliates for acquisitions and other corporate purposes. These financial transactions bear interest and are subject to review and approval by senior management, as are all related party transactions. It is the Company's policy that the Audit Committee of the Board of Directors shall review all related party transactions. The Company is prohibited from entering or continuing a material related party transaction that has not been reviewed and approved or ratified by the Audit Committee. Receivable and payable balances with related parties are shown below (in millions): At 2017 2016 Related parties receivable current: Grupo Mexico and affiliates: Mexico Generadora de Energia S. de R.L. ("MGE") $ $ Asarco LLC Grupo Mexico Compañia Perforadora Mexico S.A.P.I. de C.V. and affiliates Mexico Proyectos y Desarrollos, S.A. de C.V. and affiliates Operadora de Generadoras de Energia Mexico S.A. de C.V. — Related to the controlling group: Operadora de Cinemas S.A. de C.V. Boutique Bowling de Mexico S.A. de C.V. ​ ​ ​ ​ ​ ​ ​ ​ $ $ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Related parties payable: Grupo Mexico and affiliates: MGE $ $ Asarco LLC Mexico Proyectos y Desarrollos S.A. de C.V. and affiliates Ferrocarril Mexicano S.A. de C.V. Eolica El Retiro, S.A.P.I. de C.V. Grupo Mexico Related to the controlling group: Operadora de Cinemas S.A. de C.V. Boutique Bowling de Mexico S.A. de C.V. Mexico Transportes Aereos S.A. de C.V. ("Mextransport") Related to SCC executive officers: Breaker, S.A. de C.V. and affiliates ("Breaker") — ​ ​ ​ ​ ​ ​ ​ ​ $ $ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Purchase and sale activity: Grupo Mexico and affiliates: The following table summarize the purchase and sale activities with Grupo Mexico and its affiliates in 2017, 2016 and 2015 (in millions): 2017 2016 2015 Purchase activity Asarco LLC $ $ $ Compañia Perforadora Mexico S.A.P.I. de C.V. and affiliates — Eolica El Retiro, S.A.P.I. de C.V. Ferrocarril Mexicano, S.A. de C.V. Grupo Mexico Mexico Proyectos y Desarrollos S.A. de C.V. and affiliates MGE ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Total purchases $ $ $ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Sales activity Asarco LLC $ $ $ Compañia Perforadora Mexico S.A.P.I. de C.V. and affiliates Grupo Mexico Mexico Proyectos y Desarrollos S.A. de C.V. and affiliates — Operadora de Generadoras de Energia Mexico S.A. de C.V — — MGE ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Total sales $ $ $ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Grupo Mexico, the parent and the majority indirect stockholder of the Company, and its affiliates provide various services to the Company. These services are primarily related to accounting, legal, tax, financial, treasury, human resources, price risk assessment and hedging, purchasing, procurement and logistics, sales and administrative and other support services. The Company pays Grupo Mexico for these services and expects to continue these services in the future. In 2017, the Company made donations of $1.9 million to Fundacion Grupo Mexico, an organization dedicated to promoting the social and economic development of the communities close to the Company's Mexican operations. The Company's Mexican operations paid fees for freight services provided by Ferrocarril Mexicano, S.A de C.V., for construction services provided by Mexico Proyectos y Desarrollos, S.A. de C.V. and its affiliates, and for drilling services provided by Compañia Perforadora Mexico S.A.P.I. de C.V. All of these companies are subsidiaries of Grupo Mexico. The Company's Mexican operations purchased scrap and other residual copper mineral from Asarco, and power from MGE. Both companies are subsidiaries of Grupo Mexico. In 2005, the Company organized MGE, as a subsidiary of Minera Mexico, for the construction of two power plants to supply power to the Company's Mexican operations. In May 2010, the Company's Mexican operations granted a $350 million line of credit to MGE for the construction of the power plants. That line of credit was due on December 31, 2012 and carried an interest rate of 4.4%. In the first quarter of 2012, Controladora de Infraestructura Energetica Mexico, S. A. de C. V., an indirect subsidiary of Grupo Mexico, acquired 99.999% of MGE through a capital subscription of 1,928.6 million of Mexican pesos (approximately $150 million), reducing Minera Mexico's participation to less than 0.001%. As consequence of this change in control, MGE became an indirect subsidiary of Grupo Mexico. Additionally, at the same time, MGE paid $150 million to the Company's Mexican operations partially reducing the total debt. The remaining balance was restructured as subordinated debt of MGE. In the third quarter of 2016, MGE repaid the outstanding balance of the debt. Related to this loan, the Company recorded interest income of $4.2 million and $9.2 million in 2016 and 2015, respectively. In 2012, the Company signed a power purchase agreement with MGE, whereby MGE will supply some of the Company's Mexican operations with power through 2032. MGE completed construction of its first power plant in June 2013 and the second plant, in the second quarter of 2014. These plants are natural gas-fired combined cycle power generating units, with a net total capacity of 516.2 megawatts. The first plant began supplying power to the Company in December 2013, and the second plant began to supply power in June 2015. MGE is supplying 13.5% of its power output to third-party energy users. On August 4, 2014, Mexico Generadora de Energia Eolica S. de R.L. de C.V, an indirect subsidiary of Grupo Mexico, located in Oaxaca, Mexico, acquired Eolica el Retiro. Eolica el Retiro is a windfarm that has 37 wind turbines. This company started operations in January 2014 and started to sell power to IMMSA and other subsidiaries of Grupo Mexico in the third quarter of 2014. Eolica el Retiro is supplying approximately 27% of its power output to IMMSA. The Company sold copper cathodes, rod and anodes, as well as sulfuric acid, silver, gold and lime to Asarco. In addition, the Company received fees for building rental and maintenance services provided to Mexico Proyectos y Desarrollos, S.A. de C.V. and its affiliates and to Perforadora Mexico S.A.P.I de C.V., and for natural gas and services provided by MGE, all subsidiaries of Grupo Mexico. Companies with relationships with the controlling group: The following table summarizes the purchase and sales activities with other Larrea family companies in 2017, 2016 and 2015 (in millions): 2017 2016 2015 Purchase activity Boutique Bowling de Mexico S.A. de C.V. $ $ $ Mextransport Operadora de Cinemas S.A. de C.V. ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Total purchases $ $ $ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Sales activity Boutique Bowling de Mexico S.A. de C.V. $ $ $ Mextransport Operadora de Cinemas S.A. de C.V. ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Total sales $ $ $ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ The Larrea family controls a majority of the capital stock of Grupo Mexico, and has extensive interests in other businesses, including transportation, real estate and entertainment. The Company engages in certain transactions in the ordinary course of business with other entities controlled by the Larrea family relating to the lease of office space, air transportation and entertainment. The Company's Mexican operations paid fees for entertainment services provided by Boutique Bowling de Mexico S.A de C.V. and Operadora de Cinemas S.A. de C.V. Both companies are controlled by the Larrea family. MexTransport provides aviation services to the Company's Mexican operations. In addition, the Company received fees for building rental provided to Mextransport. This is a company controlled by the Larrea family. In addition, the Company received fees for building rental and maintenance services provided to Boutique Bowling de Mexico S.A de C.V., Operadora de Cinemas S.A. de C.V. and MexTransport. Equity Investment in Affiliate: The Company has a 44.2% participation in Compañia Minera Coimolache S.A. ("Coimolache"), which it accounts for on the equity method. Coimolache owns Tantahuatay, a gold mine located in northern Peru. It is anticipated that in the future the Company will enter into similar transactions with these same parties. Companies with relationships with SCC executive officers: The following table summarizes the purchase activities with companies with relationships to SCC executive officers in 2017, 2016 and 2015 (in millions): 2017 2016 2015 Breaker $ — $ $ Higher Technology S.A.C. — Servicios y Fabricaciones Mecanicas S.A.C. Sempertrans — — ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Total purchased $ $ $ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ In 2016, the Company purchased industrial materials from Breaker S.A. de C.V., Breaker Peru S.A.C., and Pigoba S.A. de C.V. in which the SCC´s Chief Executive Officer´s sons, Carlos Gonzalez and Alejandro Gonzalez, and son-in-law, Jorge Gonzalez, have a proprietary interest. Also, the Company purchased industrial material from Higher Technology S.A.C. and paid fees for maintenance services provided by Servicios y Fabricaciones Mecanicas S.A.C., companies in which Carlos Gonzalez, the son of SCC´s Chief Executive Officer, had a proprietary interest through June 6, 2016. Tax Agreement: On, February 28, 2017, AMC and the Company entered into a tax agreement, effective as of February 20, 2017, pursuant to which AMC, as the parent of the consolidated group of which the Company is a member and joins in the filing of a U.S. federal income tax return, (a) will be responsible for and discharge, any and all liabilities and payments due to the IRS on account of any incremental tax liabilities of the Company in connection with the potential adjustments being considered by the IRS in connection with the interest of the 2012 Judgment, (b) will not seek reimbursement, contribution or collection of any amounts of money or any other asset in connection therewith from the Company, and (c) will indemnify, defend and hold harmless the Company from any such liability, including the cost of such defense.

SEGMENT AND RELATED INFORMATION

SEGMENT AND RELATED INFORMATION:	12 Months Ended
	Dec. 31, 2017
SEGMENT AND RELATED INFORMATION:
SEGMENT AND RELATED INFORMATION:	NOTE 17—SEGMENT AND RELATED INFORMATION: Company management views Southern Copper as having three reportable segments and manages it on the basis of these segments. The reportable segments identified by the Company are: the Peruvian operations, the Mexican open-pit operations and the Mexican underground mining operations segment identified as the IMMSA unit. The three reportable segments identified are groups of mines, each of which constitute an operating segment, with similar economic characteristics, type of products, processes and support facilities, similar regulatory environments, similar employee bargaining contracts and similar currency risks. In addition, each mine within the individual group earns revenues from similar type of customers for their products and services and each group incurs expenses independently, including commercial transactions between groups. Intersegment sales are based on arm's length prices at the time of sale. These may not be reflective of actual prices realized by the Company due to various factors, including additional processing, timing of sales to outside customers and transportation cost. Added to the segment data is information regarding the Company's sales. The segments identified by the Company are: 1. Peruvian operations, which include the Toquepala and Cuajone mine complexes and the smelting and refining plants, including a precious metals plant, industrial railroad and port facilities that service both mines. The Peruvian operations produce copper, with production of by-products of molybdenum, silver and other material. 2. Mexican open-pit operations, which include La Caridad and Buenavista mine complexes and the smelting and refining plants, including a precious metals plant and a copper rod plant and support facilities that service both mines. The Mexican open-pit operations produce copper, with production of by-products of molybdenum, silver and other material. 3. Mexican underground mining operations, which include five underground mines that produce zinc, copper, silver and gold, a coal mine which produces coal and coke, and a zinc refinery. This group is identified as the IMMSA unit. The Peruvian operations include two open-pit copper mines whose mineral output is transported by rail to Ilo, Peru where it is processed at the Company's Ilo smelter and refinery, without distinguishing between the products of the two mines. The resulting product, anodes and refined copper, are then shipped to customers throughout the world. These shipments are recorded as revenue of the Company's Peruvian mines. The Mexican open-pit segment includes two copper mines whose mineral output is processed in the same smelter and refinery without distinguishing between the products of the two mines. The resultant product, anodes and refined copper, are then shipped to customers throughout the world. These shipments are recorded as revenues of the Company's Mexican open-pit mines. The Company has determined that it is necessary to classify the Peruvian open-pit operations as a separate operating segment from the Mexican open-pit operations due to the very distinct regulatory and political environments in which they operate. The Company's senior management must consider the operations in each country separately when analyzing results of the Company and making key decisions. The open-pit mines in Peru must comply with stricter environmental rules and must continually deal with a political climate that has a very distinct vision of the mining industry as compared to Mexico. In addition, the collective bargaining agreement contracts are negotiated differently in each of the countries. These key differences result in the Company taking varying decisions with regards to open-pit operations in the two countries. The IMMSA segment includes five mines whose minerals are processed in the same refinery. This segment also includes an underground coal mine. Sales of product from this segment are recorded as revenues of the Company's IMMSA unit. While the Mexican underground mines are subject to a very similar regulatory environment of the Mexican open-pit mines, the nature of the products and processes of two Mexican operations vary distinctly. These differences cause the Company's senior management to take a very different approach when analyzing results and making decisions regarding the two Mexican operations. Financial information is regularly prepared for each of the three segments and the results of the Company's operations are regularly reported to senior management on the segment basis. Senior management of the Company focus on operating income and on total assets as measures of performance to evaluate different segments and to make decisions to allocate resources to the reported segments. These are common measures in the mining industry. Financial information relating to Company's segments is as follows: Year Ended December 31, 2017 (in millions) Mexican Mexican Peruvian Corporate, other Consolidated Net sales outside of segments $ $ $ $ — $ Intersegment sales — — ) — Cost of sales (exclusive of depreciation, amortization and depletion) ) Selling, general and administrative Depreciation, amortization and depletion Exploration Environmental remediation ) — — — ) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Operating income $ $ $ $ ) Less: Interest, net ) Other income (expense) ) Income taxes ) Equity earnings of affiliate Non-controlling interest ) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Net income attributable to SCC $ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Capital investment $ $ $ $ $ Property and mine development, net $ $ $ $ $ Total assets $ $ $ $ $ Year Ended December 31, 2016 (in millions) Mexican Mexican Peruvian Corporate, other Consolidated Net sales outside of segments $ $ $ $ — $ Intersegment sales — — ) — Cost of sales (exclusive of depreciation, amortization and depletion) ) Selling, general and administrative Depreciation, amortization and depletion Exploration Environmental remediation — — — — — ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Operating income $ $ $ $ ) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Less: Interest, net ) Other income (expense) ) Income taxes ) Equity earnings of affiliate Non-controlling interest ) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Net income attributable to SCC $ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Capital investment $ $ $ $ $ Property and mine development, net $ $ $ $ $ Total assets $ $ $ $ $ Year Ended December 31, 2015 (in millions) Mexican Mexican Peruvian Corporate, other Consolidated Net sales outside of segments $ $ $ $ — $ Intersegment sales — — ) — Cost of sales (exclusive of depreciation, amortization and depletion) ) Selling, general and administrative Depreciation, amortization and depletion ) Exploration Environmental remediation — — — ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Operating income $ $ $ $ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Less: Interest, net ) Other income (expense) ) Income taxes ) Equity earnings of affiliate Non-controlling interest ) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Net income attributable to SCC $ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Capital investment(*) $ $ $ $ $ Property and mine development, net $ $ $ $ $ Total assets $ $ $ $ $ (*) Corporate, other and eliminations includes $100.4 million purchase of the El Pilar mining property acquisition. SALES VALUE PER SEGMENT: Year Ended December 31, 2017 (in millions) Mexican Mexican Peruvian Corporate, Other & Total Copper $ $ $ $ ) $ Molybdenum — — Silver ) Zinc — — ) Other ) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Total $ $ $ $ ) $ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended December 31, 2016 (in millions) Mexican Mexican Peruvian Corporate, Other & Total Copper $ $ $ $ ) $ Molybdenum — — Silver ) Zinc — — — Other ) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Total $ $ $ $ ) $ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended December 31, 2015 (in millions) Mexican Mexican Peruvian Corporate, Other & Total Copper $ $ $ $ ) $ Molybdenum — — Silver ) Zinc — — — Other ) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Total $ $ $ $ ) $ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ NET SALES AND GEOGRAPHICAL INFORMATION: The geographic breakdown of the Company's sales for the three years ended December 31, 2017 were as follows (in millions): 2017 2016 2015 The Americas: Mexico $ $ $ United States Peru Brazil Chile Other American countries Europe: Switzerland Italy Other European countries Asia: Singapore Japan Other Asian countries ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Total $ $ $ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ PROVISIONAL SALES PRICE: At December 31, 2017, the Company has recorded provisionally priced sales of copper at average forward prices per pound, and molybdenum at the year-end market price per pound. These sales are subject to final pricing based on the average monthly copper prices on the London Metal Exchange ("LME") or New York Commodities Exchange ("COMEX") and Dealer Oxide molybdenum prices in the future month of settlement. Following are the provisionally priced copper and molybdenum sales outstanding at December 31, 2017: Sales volume Priced at Month of settlement Copper January through March 2018 Molybdenum January through March 2018 Provisional sales price adjustments included in accounts receivable and net sales were as follows at December, 31 (in millions): At 2017 2016 Copper $ $ Molybdenum ) ​ ​ ​ ​ ​ ​ ​ ​ Total $ $ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Management believes that the final pricing of these sales will not have a material effect on the Company's financial position or results of operations. LONG-TERM SALES CONTRACTS: The following are the significant outstanding long-term contracts: In 2013, a five year copper cathodes sales agreement was signed with Mitsui, with shipments beginning in 2015. Mitsui and the Company will negotiate market terms and conditions for annual contracts no later than November 30 of the year prior to shipment. The contract considers the following annual volumes of copper cathodes; 6,000 tons for 2015 and 48,000 tons for each of the years from 2016 through 2019. The contract volume would increase by 24,000 tons the year after Tia Maria reaches full production capacity. Failure to reach an agreement on market terms would cancel the annual contract but not the long-term agreement. Under the terms of the agreement all shipments would be to Asia and there are no exclusivity rights for Mitsui or commissions included. This contract may be renewed for additional five year periods, upon the agreement of both parties. Under the terms of a sales contract with Molibdenos y Metales, S.A., SPCC Peru Branch is required to supply approximately 26,220 tons of molybdenum concentrates from 2017 through 2019. This contract may be extended for one more calendar year during each October to maintain a three year period unless either party decides to terminate the agreement. The sale price of the molybdenum concentrates is based on the monthly average of the high and low Metals Week Dealer Oxide quotation. The roasting charge deduction is agreed based on international market terms. Under the terms of a sales contract with Molymex, S.A. de C.V., Operadora de Minas de Nacozari, S.A. de C.V. and Operadora de Minas e Instalaciones Mineras, S.A. de C. V. are required to supply at least the 80% of their molybdenum concentrates production from 2016 through 2019. The sale price of the molybdenum concentrate is based on the monthly average of the high and low Metals Week Dealer Oxide quotation. The roasting charge deduction is negotiated based on international market terms.

QUARTERLY DATA (unaudited)

QUARTERLY DATA (unaudited)	12 Months Ended
	Dec. 31, 2017
QUARTERLY DATA (unaudited)
QUARTERLY DATA (unaudited)	NOTE 18—QUARTERLY DATA (unaudited) 2017 (in millions, except per share data) 1 st 2 nd 3 rd 4 th Year Net sales $ $ $ $ $ Gross profit(1) $ $ $ $ $ Operating income $ $ $ $ $ Net income (loss) $ $ $ $ ) $ Net income (loss) attributable to SCC $ $ $ $ ) $ Per share amounts attributable to SCC: Net earnings basic and diluted $ $ $ $ ) $ Dividend per share $ $ $ $ $ 2016 1 st 2 nd 3 rd 4 th Year Net sales $ $ $ $ $ Gross profit(1) $ $ $ $ $ Operating income $ $ $ $ $ Net income $ $ $ $ $ Net income attributable to SCC $ $ $ $ $ Per share amounts attributable to SCC: Net earnings basic and diluted $ $ $ $ $ Dividend per share $ $ $ $ $ (1) Gross profit is the result of net sales less cost of sales (excluding depreciation, amortization and depletion) and less depreciation, amortization and depletion.

SUBSEQUENT EVENTS

SUBSEQUENT EVENTS	12 Months Ended
	Dec. 31, 2017
SUBSEQUENT EVENTS:
SUBSEQUENT EVENTS:	NOTE 19—SUBSEQUENT EVENTS DIVIDENDS: On January 25, 2018, the Board of Directors authorized a dividend of $0.30 per share paid on February 27, 2018, to shareholders of record at the close of business on February 13, 2018. MICHIQUILLAY PROJECT ACQUISITION: On February 20, 2018, the Company won the public bidding process for the Michiquillay project in Cajamarca, Peru. The Company's tender proposed a price of $400 million and an annual royalty of 3% on net sales. Michiquillay is a mining project with 1,150 million tons of mineralized material with a copper content of 0.63%. The estimated capital investment is approximately $2,500 million and it is expected to start production in 2025 with a production of 225,000 tons of copper per year for an initial estimated mine life of more than 25 years. SAN MARTIN STRIKE: On February 28, 2018, the striking workers of the San Martín mine of IMMSA held an election to vote on the union that will hold the collective bargaining agreement at the San Martín mine. The Federacíon Nacional de Sindicatos Independientes (the National Federation of Independent Unions), won the vote by a majority. As a result, once the Federal Mediation and Arbitration Board issues a ruling recognizing the election results, IMMSA will be entitled to negotiate and enter into a collective bargaining agreement with the Federacíon Nacional de Sindicatos Independientes to end the strike that began in 2007 and resume operations at the San Martín Mine.

Schedule II - Valuation and Qua

Schedule II - Valuation and Qualifying Accounts and Reserves	12 Months Ended
	Dec. 31, 2017
Schedule II Valuation and Qualifying Accounts and Reserves
Schedule II Valuation and Qualifying Accounts and Reserves	Schedule II Valuation and Qualifying Accounts and Reserves (in millions): Additions Balance at Charged to Additions Deduction/ Balance at Reserve deducted in balance sheet to which applicable: Accounts Receivable: 2017 $ — $ 2016 $ — — $ 2015 $ — — $ Notes issued under par: 2017 $ — — $ 2016 $ — — $ 2015 $ — $ Valuation allowance: 2017 $ — — — $ 2016 $ — — — — $ — 2015 $ — — — — $ —

SUMMARY OF SIGNIFICANT ACCOUN30

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES: (Policies)	12 Months Ended
	Dec. 31, 2017
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES:
Principles of consolidation	Principles of consolidation— The consolidated financial statements include the accounts of subsidiaries of which the Company has voting control, in accordance with Accounting Standards Codification ("ASC") 810 Consolidation . Such financial statements are prepared in accordance with accounting principles generally accepted in the United States ("U.S. GAAP").
Use of estimates	Use of estimates— The preparation of financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities, and disclosure of contingent assets and liabilities at the date of the financial statements, and the reported amounts of revenues and expenses during the reporting period. Significant items subject to such estimates and assumptions include the carrying value of ore reserves that are the basis for future cash flow estimates and amortization calculations; environmental reclamation, closure and retirement obligations; estimates of recoverable copper in mill and leach stockpiles; asset impairments (including estimates of future cash flows); unrecognized tax benefits; valuation allowances for deferred tax assets; and fair value of financial instruments. Management bases its estimates on the Company's historical experience and on various other assumptions that are believed to be reasonable under the circumstances. Actual results could differ from those estimates.
Revenue recognition	Revenue recognition— Substantially all of the Company's copper and non-copper products are sold under annual or other longer-term contracts. Revenue is recognized when title passes to the customer. The passing of title is based on terms of the contract, generally upon shipment. Copper and non-copper revenues are determined based on the monthly average of prevailing commodity prices according to the terms of the contracts. The Company provides allowances for doubtful accounts based upon historical bad debt and claims experience and periodic evaluation of specific customer accounts. For certain of the Company's sales of copper and molybdenum products, customer contracts allow for pricing based on a month subsequent to shipping, in most cases within the following three months and occasionally in some cases a few additional months. In such cases, revenue is recorded at a provisional price at the time of shipment. The provisionally priced copper sales are adjusted to reflect forward LME or COMEX copper prices at the end of each month until a final adjustment is made to the price of the shipments upon settlement with customers pursuant to the terms of the contract. In the case of molybdenum sales, for which there are no published forward prices, the provisionally priced sales are adjusted to reflect the market prices at the end of each month until a final adjustment is made to the price of the shipments upon settlement with customers pursuant to the terms of the contract. These provisional pricing arrangements are accounted for separately from the contract as an embedded derivative instrument under ASC 815-30 "Derivatives and Hedging—Cash Flow Hedges." The Company sells copper in concentrate, anode, blister and refined form at industry standard commercial terms. Net sales include the invoiced value of copper, zinc, silver, molybdenum, sulfuric acid and other metals and the corresponding fair value adjustment of the related forward contract of copper and molybdenum.
Shipping and handling fees and costs	Shipping and handling fees and costs— Amounts billed to customers for shipping and handling are classified as sales. Amounts incurred for shipping and handling are included in cost of sales (exclusive of depreciation, amortization and depletion).
Cash and cash equivalents	Cash and cash equivalents— Cash and cash equivalents include bank deposits, certificates of deposit and short-term investment funds with original maturities of three months or less at the date of purchase. The carrying value of cash and cash equivalents approximates fair value.
Short-term investments	Short-term investments— The Company accounts for short-term investments in accordance with ASC 320-10 "Investments Debt and Equity Securities—Recognition." The Company determines the appropriate classification of all short-term investments as held-to-maturity, available-for-sale or trading at the time of purchase and re-evaluates such classifications as of each balance sheet date. Unrealized gains and losses on available-for-sale investments, net of taxes, are reported as a component of accumulated other comprehensive income (loss) in stockholders' equity, unless such loss is deemed to be other than temporary.
Inventories	Inventories— The Company principally produces copper and, in the production process, obtains several by-products, including molybdenum, silver, zinc, sulfuric acid and other metals. Metal inventories, consisting of work-in-process and finished goods, are carried at the lower of average cost or market. Costs of work-in-process inventories and finished goods mainly include power, labor, fuel, operating and repair materials, depreciation, amortization, depletion, and other necessary costs related to the extraction and processing of ore, including mining, milling, concentrating, smelting, refining, leaching and chemical processing. Costs incurred in the production of metal inventories exclude general and administrative costs. Once molybdenum, silver, zinc and other by-products are identified, they are transferred to their respective production facilities and the incremental cost required to complete production is assigned to their inventory value. Work-in-process inventories represent materials that are in the process of being converted into a saleable product. Conversion processes vary depending on the nature of the copper ore and the specific mining operation. For sulfide ores, processing includes milling and concentrating and results in the production of copper and molybdenum concentrates. Finished goods include saleable products (e.g., copper concentrates, copper anodes, copper cathodes, copper rod, molybdenum concentrate and other metallurgical products). Supplies inventories are carried at the lower of average cost or market.
Long-term inventory - Ore stockpiles on leach pads	Long-term inventory—Ore stockpiles on leach pads. The leaching process is an integral part of the mining operations carried out at the Company's open-pit mines. The Company capitalizes the production cost of leachable material at its Toquepala, La Caridad and Buenavista mines recognizing it as inventory. This cost includes mining and haulage costs incurred to deliver ore to leach pads, depreciation, amortization, depletion and site overhead costs. The estimates of recoverable mineral content contained in the leaching dumps are supported by engineering studies. As the production cycle of the leaching process is significantly longer than the conventional process of concentrating, smelting and electrolytic refining, the Company includes on its balance sheet current leach inventory (included in work-in-process inventories) and long-term leach inventory. Amortization of leachable material is recorded by the units of production method.
Property	Property— Property is recorded at acquisition cost, net of accumulated depreciation and amortization. Cost includes major expenditures for improvements and replacements, which extend useful lives or increase capacity and interest costs associated with significant capital additions. Maintenance, repairs, normal development costs at existing mines and gains or losses on assets retired or sold are reflected in earnings as incurred. Buildings and equipment are depreciated on the straight-line method over estimated lives from five to 40 years or the estimated life of the mine if shorter.
Mine development	Mine development— Mine development includes primarily the cost of acquiring land rights to an exploitable ore body, pre-production stripping costs at new mines that are commercially exploitable, costs associated with bringing new mineral properties into production, and removal of overburden to prepare unique and identifiable areas outside the current mining area for such future production. Mine development costs are amortized on a unit of production basis over the remaining life of the mines. There is a diversity of practices in the mining industry in the treatment of drilling and other related costs to delineate new ore reserves. The Company follows the practices outlined in the next two paragraphs in its treatment of drilling and related costs. Drilling and other associated costs incurred in the Company's efforts to delineate new resources, whether near-mine or Greenfield are expensed as incurred. These costs are classified as mineral exploration costs. Once the Company determines through feasibility studies that proven and probable reserves exist and that the drilling and other associated costs embody a probable future benefit that involves a capacity, singly or in combination with other assets, to contribute directly or indirectly to future net cash inflow, then the costs are classified as mine development costs. These mine development costs incurred prospectively to develop the property are capitalized as incurred, until the commencement of production, and are amortized using the units of production method over estimated life of the ore body. During the production stage, drilling and other related costs incurred to maintain production are included in production cost in the period in which they are incurred. Drilling and other related costs incurred in the Company's efforts to delineate a major expansion of reserves at an existing production property are expensed as incurred. Once the Company determines through feasibility studies that proven and probable incremental reserves exist and that the drilling and other associated costs embody a probable future benefit that involves a capacity, singly or in combination with other assets, to contribute directly or indirectly to future net cash inflow, then the costs are classified as mine development costs. These incremental mine development costs are capitalized as incurred, until the commencement of production and amortized using the units of production method over the estimated life of the ore body. A major expansion of reserves is one that increases total reserves at a property by approximately 10% or more. For the years ended December 31, 2017, 2016 and 2015, the Company did not capitalize any drilling and related costs.
Asset retirement obligations (reclamation and remediation costs)	Asset retirement obligations (reclamation and remediation costs)— The fair value of a liability for asset retirement obligations is recognized in the period in which the liability is incurred. The liability is measured at fair value and is adjusted to its present value in subsequent periods as accretion expense is recorded. The corresponding asset retirement costs are capitalized as part of the carrying value of the related long-lived assets and depreciated over the asset's useful life.
Intangible assets	Intangible assets— Intangible assets include primarily the excess amount paid over the book value for investment shares which are presented as mining concessions, and mining and engineering development studies. Intangible assets are carried at acquisition costs, net of accumulated amortization and are amortized principally on a unit of production basis over the estimated remaining life of the mines. Intangible assets are reviewed for impairment whenever events or changes in circumstances indicate that the carrying amount of the asset may not be recoverable.
Debt issuance costs	Debt issuance costs— Debt issuance costs related to a recognized debt liability are presented in the balance sheet as a direct deduction from the carrying amount of that debt liability, consistent with the treatment of a debt discount.
Ore reserves	Ore reserves— The Company periodically reevaluates estimates of its ore reserves, which represent the Company's estimate as to the amount of unmined copper remaining in its existing mine locations that can be produced and sold at a profit. Such estimates are based on engineering evaluations derived from samples of drill holes and other openings, combined with assumptions about copper market prices and production costs at each of the respective mines. The Company updates its estimate of ore reserves at the beginning of each year. In this calculation, the Company uses current metal prices which are defined as the average metal price over the preceding three years. The current price per pound of copper, as defined, was $2.50, $2.61 and $2.99 at the end of 2017, 2016 and 2015, respectively. The ore reserve estimates are used to determine the amortization of mine development and intangible assets. Once the Company determines through feasibility studies that proven and probable reserves exist and that the drilling and other associated costs embody a probable future benefit that involves a capacity, singly or in combination with other assets, to contribute directly or indirectly to future net cash inflow, then the costs are classified as mine development costs and the Company discloses the related ore reserves.
Exploration	Exploration— Tangible and intangible costs incurred in the search for mineral properties are charged against earnings when incurred.
Income taxes	Income taxes— Provisions for income taxes are based on taxes payable or refundable for the current year and deferred taxes on temporary differences between the amount of taxable income and pretax financial income and between the tax bases of assets and liabilities and their reported amounts in the financial statements. Deferred tax assets and liabilities are included in the financial statements at currently enacted income tax rates applicable to the period in which the deferred tax assets and liabilities are expected to be realized and settled as prescribed in ASC 740 "Income taxes." As changes in tax laws or rates are enacted, deferred tax assets and liabilities are adjusted through the provision for income taxes. Deferred income tax assets are reduced by any benefits that, in the opinion of management, are more likely not to be realized. The Company's operations involve dealing with uncertainties and judgments in the application of complex tax regulations in multiple jurisdictions. The final taxes paid are dependent upon many factors, including negotiations with taxing authorities in various jurisdictions and resolution of disputes arising from federal, state, and international tax audits. The Company recognizes potential liabilities and records tax liabilities for anticipated tax audit issues in the U.S. and other tax jurisdictions based on its estimate of whether, and the extent to which, additional taxes will be due. The Company follows the guidance of ASC 740 "Income taxes" to record these liabilities. (See Note 7 "Income taxes" of the consolidated financial statements for additional information). The Company adjusts these reserves in light of changing facts and circumstances; however, due to the complexity of some of these uncertainties, the ultimate resolution may result in a payment that is materially different from the Company's current estimate of the tax liabilities. If its estimate of tax liabilities proves to be less than the ultimate assessment, an additional charge to expense would result. If payment of these amounts ultimately proves to be less than the recorded amounts, the reversal of the liabilities would result in tax benefits being recognized in the period when the Company determines the liabilities are no longer necessary. The Company classifies income tax-related interest and penalties as income taxes in the financial statements, as well as interest and penalties, if any, related to unrecognized tax benefits. On December 22, 2017, the U.S. government enacted the "Tax Cuts and Jobs Act" (the "Act"). The Act contains numerous provisions, the following of which most significantly impact the Company: (i) a decrease in the corporate tax rate from 35% to 21%; (ii) a transition of the U.S. taxation of international operation from a worldwide system to a quasi-territorial system and a one-time transition tax on the mandatory deemed repatriation of cumulative foreign earnings as of December 31, 2017, (iii) generally eliminates U.S. federal income taxes on dividends from foreign subsidiaries, requiring a current inclusion in U.S. federal taxable income of certain earnings of controlled foreign corporations and (iv) limitations on the use of foreign tax credits to reduce the U.S. income tax liability. The U.S. Securities and Exchange Commission ("SEC") issued Staff Accounting Bulletin No. 118 ("SAB 118"), which provides guidance on accounting for the tax effects of the Act. The Company has adopted SAB 118. Accordingly, the provisions of the Act deemed most relevant to the Company have been considered in preparation of its financial statements as of December 31, 2017 based on the Company's best estimate. See further disclosure regarding the impacts of the Act and the adoption of SAB 118 in Note 7 to the accompanying consolidated financial statements.
Foreign exchange	Foreign exchange— The Company's functional currency is the U.S. dollar. As required by local law, both the Peruvian Branch and Minera Mexico maintain their books of accounts in Peruvian soles and Mexican pesos, respectively. Foreign currency assets and liabilities are remeasured into U.S. dollars at current exchange rates, except for non-monetary items such as inventory, property, intangible assets and other assets which are remeasured at historical exchange rates. Revenues and expenses are generally translated at actual exchange rates in effect during the period, except for those items related to balance sheet amounts that are remeasured at historical exchange rates. Gains and losses from foreign currency remeasurement are included in earnings of the period. Gains and (losses) resulting from foreign currency transactions are included in "Cost of sales (exclusive of depreciation, amortization and depletion)."
Asset impairments	Asset impairments— The Company evaluates long-term assets when events or changes in economic circumstances indicate that the carrying amount of such assets may not be recoverable. These evaluations are based on business plans that are prepared using a time horizon that is reflective of the Company's expectations of metal prices over its business cycle. The Company is currently using a long-term average copper price and an average molybdenum price for impairment tests, reflective of what the Company believes is the lower level of the current price environment. The results of its impairment tests using these long-term copper and molybdenum prices show no impairment in the carrying value of their assets. In recent years testing using assumptions for long-term average prices have resulted in stricter evaluation for impairment analysis than would the higher three year average prices for copper and molybdenum prices. Should this situation reverse in the future with three year average prices below the long-term price assumption, the Company would assess the need to use the three year average prices in its evaluations. The Company uses an estimate of the future undiscounted net cash flows of the related asset or asset group over the remaining life to measure whether the assets are recoverable and measures any impairment by reference to fair value.
Other comprehensive income	Other comprehensive income— Comprehensive income represents changes in equity during a period, except those resulting from investments by owners and distributions to owners. During the fiscal years ended December 31, 2017, 2016 and 2015, the components of "other comprehensive income (loss)" were, the unrecognized gain (loss) on employee benefit obligations and foreign currency translation adjustments.
Business segments	Business segments— Company management views Southern Copper as having three reportable segments and manages it on the basis of these segments. The segments identified by the Company are: 1) the Peruvian operations, which include the two open-pit copper mines in Peru and the plants and services supporting such mines, 2) the Mexican open-pit copper mines, which include La Caridad and Buenavista mine complexes and their supporting facilities and 3) the Mexican underground mining operations, which include five underground mines that produce zinc, lead, copper, silver and gold, a coal mine and a zinc refinery. Please see Note 17 "Segments and Related Information." Senior management of the Company focus on operating income as measure of performance to evaluate different segments, and to make decisions to allocate resources to the reported segments. This is a common measure in the mining industry.
NEW ACCOUNTING STANDARDS	ADOPTION OF REVENUE RECOGNITION STANDARD In May 2014, the FASB issued ASU 2014-09 "Revenue from Contracts with Customers" (Topic 606). The objective of the new revenue standard is to provide a single comprehensive revenue recognition model for all contracts with customers to improve comparability within industries, across industries and across capital markets. The core principle of the standard is that the Company should recognize revenue to represent the transfer of promised goods or services to customers in an amount that reflects the consideration to which the Company expects to be entitled in exchange for those goods or services. The Company should apply the following five steps to achieve the core principle: Step 1: Identify the contract(s) with a customer. The guidance also specifies the accounting for some costs to obtain or fulfill a contract with a customer. Additionally, the Company should disclose sufficient qualitative and quantitative information to enable users of financial statements to understand the nature, amount, timing, and uncertainty of revenue and cash flows arising from contracts with customers. In March 2016, The FASB issued ASU 2016-08 Revenue from Contracts with Customers—(Topic 606) Principal versus Agent Considerations (Reporting Revenue Gross versus Net). This update clarifies the implementation guidance on principal versus agent considerations. When another party is involved in providing goods or services to a customer, an entity is required to determine whether the nature of its promise is to provide the specified good or service itself (that is, the entity is a principal) or to arrange for that good or service to be provided by the other party (that is, the entity is an agent). This revenue standard is effective for the first interim period within annual reporting periods beginning after December 15, 2017, and early adoption is not permitted. The Company has adopted the new guidance effective January 1, 2018, applying the modified retrospective approach. Under this approach, the results for reporting periods beginning after January 1, 2018 will be presented in the consolidated financial statements under the guidance, while prior period amounts will not be adjusted and will continue to be reported under the guidance in effect for those periods. Upon adoption by the Company, no cumulative effect adjustment is required to be recognized at January 1, 2018, as the adoption of the standard has not resulted in a change to the way the Company recognizes its revenue. The Company will apply the related disclosure requirements of the new standard beginning in 2018. OTHER NEW ACCOUNTING STANDARDS In January 2016, The FASB issued ASU 2016-01 "Financial instruments—Overall (Subtopic 825-10): Recognition and Measurement of Financial Assets and Financial Liabilities" which requires entities to measure equity investments that do not result in consolidation and are not accounted for under the equity method at fair value and to recognize any changes in fair value in net income. This update also includes certain disclosure requirements. This update is effective in fiscal years, including interim periods, beginning after December 15, 2017, and upon adoption, an entity should apply the amendments with the cumulative effect of initially applying the guidance recognized at January 1, 2018. Early adoption is not permitted. The Company has completed its assessment of the adoption of this standard and has determined that it will not have a material impact on its consolidated financial information. On February 25, 2016, the FASB issued ASU 2016-02 "Leases" (Topic 842). This Update significantly modifies the accounting model of leases for lessees; as it requires them to recognize assets and liabilities in the balance sheet for virtually all leases. However, the classification of leases as finance leases or operating leases is maintained for lessees. In addition, for leases with a term of 12 months or less, a lessee can elect by class of underlying asset not to record assets and liabilities on the balance sheet, and recognize lease expense on a straight-line basis over the lease term. The lessor accounting model for leases remains mostly unchanged from previous guidance, except for specific profit recognition requirements which were modified in order to align them to the new revenue recognition standard issued by the FASB, and the lease classification criteria, to ensure consistency with those for a lessee. The amendments in this Update are effective for public business entities for fiscal years, and interim periods within those fiscal years, beginning after December 15, 2018 and early adoption is permitted. The Company is evaluating the impact of the adoption of this new standard on the consolidated financial information. In June 2016, the FASB issued ASU 2016-13 "Financial Instruments—Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments" This ASU amends guidance on reporting credit losses for assets held at amortized cost basis and available for sale debt securities and requires a financial asset (or a group of financial assets) measured at amortized cost basis to be presented at the net amount expected to be collected. The allowance for credit losses is a valuation account that is deducted from the amortized cost basis of the financial asset(s) to present the net carrying value at the amount expected to be collected on the financial asset. For available for sale debt securities, credit losses should be measured in a manner similar to current GAAP, however Topic 326 will require that credit losses be presented as an allowance rather than as a write-down. This update is effective for fiscal years beginning after December 15, 2019, including interim periods within those fiscal years. The Company is evaluating the impact of the adoption of this new standard on the consolidated financial information. Other ASUs issued by the FASB that are pending adoption as of December 31, 2017 are not anticipated to have a significant impact on the Company's consolidated financial statements.

SHORT-TERM INVESTMENTS_ (Tables

SHORT-TERM INVESTMENTS: (Tables)	12 Months Ended
	Dec. 31, 2017
SHORT-TERM INVESTMENTS:
Schedule of short-term investments	Short-term investments were as follows ($ in millions): At 2017 2016 Trading securities $ $ Weighted average interest rate % % Available-for-sale $ $ Weighted average interest rate % % ​ ​ ​ ​ ​ ​ ​ ​ Total $ $ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​
Summary of activities of short-term investments	The following table summarizes the activity of these investments by category (in millions): Years ended 2017 2016 Trading: Interest earned $ $ Unrealized gain (loss) at December 31, $ $ Available-for-sale: Interest earned (* ) (* ) Investment redeemed $ $ (*) Less than $0.1 million
Schedule of contractual maturities of the Company's available-for-sale debt securities	At December 31, 2017 and 2016, contractual maturities of the available-for-sale debt securities are as follows (in millions): 2017 2016 One year or less $ — $ — Maturing after one year through five years — — Maturing after five years through ten years — — Due after 10 years ​ ​ ​ ​ ​ ​ ​ ​ Total debt securities $ $ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​

INVENTORIES_ (Tables)

INVENTORIES: (Tables)	12 Months Ended
	Dec. 31, 2017
INVENTORIES:
Schedule of inventories	At December 31, (in millions) 2017 2016 Inventory, current: Metals at average cost: Finished goods $ $ Work-in-process Ore stockpiles on leach pads Supplies at average cost ​ ​ ​ ​ ​ ​ ​ ​ Total current inventory $ $ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Inventory, long-term: Ore stockpiles on leach pads $ $ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​

PROPERTY_ (Tables)

PROPERTY: (Tables)	12 Months Ended
	Dec. 31, 2017
PROPERTY:
Schedule of major classes of property, plant and equipment	At December 31, (in millions) 2017 2016 Buildings and equipment $ $ Construction in progress Mine development Mineral assets Land, other than mineral ​ ​ ​ ​ ​ ​ ​ ​ Total property Accumulated depreciation, amortization and depletion ) ) ​ ​ ​ ​ ​ ​ ​ ​ Total property and mine development, net $ $ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​

INTANGIBLE ASSETS_ (Tables)

INTANGIBLE ASSETS: (Tables)	12 Months Ended
	Dec. 31, 2017
INTANGIBLE ASSETS:
Schedule of major classes of intangible assets and goodwill	At December 31, (in millions) 2017 2016 Mining concessions $ $ Mine engineering and development studies Software ​ ​ ​ ​ ​ ​ ​ ​ Accumulated amortization: Mining concessions ) ) Mine engineering and development studies ) ) Software ) ) ​ ​ ​ ​ ​ ​ ​ ​ ) ) Goodwill ​ ​ ​ ​ ​ ​ ​ ​ Intangible assets, net $ $ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​
Schedule of estimated amortization of intangible assets for future periods	Estimated amortization expense (in millions): 2018 $ 2019 2020 2021 2022 ​ ​ ​ ​ ​ Total 2018 - 2022 $ ​ ​ ​ ​ ​ Average annual $ ​ ​ ​ ​ ​

INCOME TAXES_ (Tables)

INCOME TAXES: (Tables)	12 Months Ended
	Dec. 31, 2017
INCOME TAXES:
Components of the provision for income taxes	(in millions) 2017 2016 2015 U.S. federal and state: Current $ — $ — $ — Deferred ) ) Uncertain tax positions ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ) ) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Foreign (Peru and Mexico): Current Deferred ) ) ) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Total provision for income taxes $ $ $ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​
Schedule of source of income	(in millions) 2017 2016 2015 Earnings by location: U.S. $ ) $ ) $ ) Foreign Peru ) Mexico ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Earnings before taxes on income $ $ $ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​
Reconciliation of the statutory income tax rate to the effective tax rate	The reconciliation of the statutory income tax rate to the effective tax rate for the three years ended December 31, 2017, is as follows (in percentage points): 2017 2016 2015 Expected tax at U.S. statutory rate % % % Foreign tax at other than statutory rate, net of foreign tax credit benefit(1) Percentage depletion ) ) ) Other permanent differences — Valuation allowance on US deferred tax assets, foreign tax credits and US tax effect on Peruvian deferred — — Decrease in US deferred tax asset due to tax rate changes — — US one time transition tax on accumulated foreign earnings — — Increase (decrease) in unrecognized tax benefits for uncertain tax positions Repatriated foreign earnings ) — Amounts (over) / under provided in prior years ) ) ) Other ) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Effective income tax rate % % % ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ (1) Foreign tax at other than statutory rates, net of foreign tax credit benefit, also includes the effects of permanent differences in Peru and Mexico, that are determined at the local statutory rate.
Schedule of deferred tax assets and liabilities	At December 31, (in millions) 2017 2016 Assets: Inventories $ $ Capitalized exploration expenses U.S. foreign tax credit carryforward, net of FIN 48 liability U.S. tax effect of Peruvian deferred tax liability Property, plant and equipment — Reserves Mexican tax on consolidated dividends Prepaids — Valuation allowance on US deferred tax assets, foreign tax credits and US tax effect on Peruvian deferred ) — Other ​ ​ ​ ​ ​ ​ ​ ​ Total deferred tax assets ​ ​ ​ ​ ​ ​ ​ ​ Liabilities: Property, plant and equipment ) — Deferred charges ) ) Unremitted foreign earnings — ) Other ) ) ​ ​ ​ ​ ​ ​ ​ ​ Total deferred tax liabilities ) ) ​ ​ ​ ​ ​ ​ ​ ​ Total net deferred tax (liabilities) / assets $ ) $ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​
Summary of expiry of foreign tax credits	Year Amount 2022 2023 2024 2025 2026 ​ ​ ​ ​ ​ Total $ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​
Summary of income tax rate and dividend tax rate due to change in enacted tax law	Year Income Dividend 2015 - 2016 % % 2017 and later % %
Schedule of reconciliation of amount of unrecognized tax benefits	The total amount of unrecognized tax benefits in 2017, 2016 and 2015, was as follows (in millions): 2017 2016 2015 Unrecognized tax benefits, opening balance $ $ $ Gross increases—tax positions in prior period ) Gross increases—current-period tax positions — Decreases related to settlements with taxing authorities — ) — ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ) ) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Unrecognized tax benefits, ending balance $ $ $ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​
Summary of tax years remaining open to examination and adjustment in major tax jurisdictions	Peru: 2012 and all subsequent years U.S.: 2012 and all subsequent years Mexico: 2012 and all subsequent years

WORKERS' PARTICIPATION_ (Tables

WORKERS' PARTICIPATION: (Tables)	12 Months Ended
	Dec. 31, 2017
WORKERS' PARTICIPATION:
Schedule of workers' participation expense	Workers' participation expense for the three years ended December 31, 2017 was as follows (in millions): 2017 2016 2015 Current $ $ $ Deferred ) ) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ $ $ $ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​

ASSET RETIREMENT OBLIGATION_ (T

ASSET RETIREMENT OBLIGATION: (Tables)	12 Months Ended
	Dec. 31, 2017
ASSET RETIREMENT OBLIGATION:
Summary of asset retirement obligation activity	The following table summarizes the asset retirement obligation activity for years ended December 31, 2017 and 2016 (in millions): 2017 2016 Balance as of January 1 $ $ Changes in estimates ) — Additions — Closure payments ) ) Accretion expense ​ ​ ​ ​ ​ ​ ​ ​ Balance as of December 31, $ $ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​

FINANCING_ (Tables)

FINANCING: (Tables)	12 Months Ended
	Dec. 31, 2017
FINANCING:
Schedule of long-term debt	Long-term debt (in millions): Face Issuance Issuance Carrying 5.375% Senior unsecured notes due 2020 $ $ ) $ ) $ 3.500% Senior unsecured notes due 2022 ) ) 3.875% Senior unsecured notes due 2025 ) ) 9.250% Yankee Bonds due 2028 — — 7.500% Senior unsecured notes due 2035 ) ) 6.750% Senior unsecured notes due 2040 ) ) 5.250% Senior unsecured notes due 2042 ) ) 5.875% Senior unsecured notes due 2045 ) ) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Total $ $ ) $ ) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Less, current portion — ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Total long-term debt $ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Face Issuance Issuance Carrying 5.375% Senior unsecured notes due 2020 $ $ ) $ ) $ 3.500% Senior unsecured notes due 2022 ) ) 3.875% Senior unsecured notes due 2025 ) ) 9.250% Yankee Bonds due 2028 — — 7.500% Senior unsecured notes due 2035 ) ) 6.750% Senior unsecured notes due 2040 ) ) 5.250% Senior unsecured notes due 2042 ) ) 5.875% Senior unsecured notes due 2045 ) ) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Total $ $ ) $ ) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Less, current portion — ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Total long-term debt $ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​
Schedule of aggregate maturities of the outstanding borrowings	Years Principal (in millions) 2018 $ — 2019 — 2020 2021 — 2022 Thereafter ​ ​ ​ ​ ​ Total $ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ (*) Total debt maturities do not include the debt discount valuation account of $94.1 million.

BENEFIT PLANS_ (Tables)

BENEFIT PLANS: (Tables)	12 Months Ended
	Dec. 31, 2017
Post retirement defined benefit plans
Components of net periodic benefit costs
Schedule of the components of net periodic benefit costs	Years ended (in millions) 2017 2016 2015 Service cost $ $ $ Interest cost Expected return on plan assets ) ) ) Amortization of transition assets, net Amortization of net actuarial loss — — ) Settlement / Curtailment ) — Amortization of net loss/(gain) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Net periodic benefit cost $ ) $ ) $ ) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​
Schedule of changes in the benefit obligation and plan assets, the funded status of the plans and the amount recognized in balance sheet and accumulated other comprehensive income	As of (in millions) 2017 2016 Change in benefit obligation: Projected benefit obligation at beginning of year $ $ Service cost Interest cost Settlement ) Benefits paid ) ) Actuarial (gain)/loss ) Actuarial gain assumption changes ) Inflation adjustment ) ​ ​ ​ ​ ​ ​ ​ ​ Projected benefit obligation at end of year $ $ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Change in plan assets: Fair value of plan assets at beginning of year $ $ Actual return on plan assets Employer contributions ) ) Benefits paid ) ) Currency exchange rate adjustment ) ​ ​ ​ ​ ​ ​ ​ ​ Fair value of plan assets at end of year $ $ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Funded status at end of year: $ $ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ASC-715 amounts recognized in statement of financial position consists of: Non-current assets $ $ ​ ​ ​ ​ ​ ​ ​ ​ Total $ $ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ASC-715 amounts recognized in accumulated other comprehensive income (net of income taxes of $(2.0) million and $(3.3) million in 2017 and 2016, respectively) consists of: Net loss (gain) $ $ Prior service cost ​ ​ ​ ​ ​ ​ ​ ​ Total $ $ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​
Schedule of changes in accumulated other comprehensive income	(in millions) 2017 2016 Reconciliation of accumulated other comprehensive income: Accumulated other comprehensive income at beginning of plan year $ $ Net loss/(gain) amortized during the year ) ) Net loss/(gain) occurring during the year ) Prior service cost (credit) — Currency exchange rate adjustment ) ​ ​ ​ ​ ​ ​ ​ ​ Net adjustment to accumulated other comprehensive income (net of income taxes of $1.3 million and $(3.3) million in 2017 and 2016, respectively) ) ​ ​ ​ ​ ​ ​ ​ ​ Accumulated other comprehensive income at end of plan year $ $ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​
Summary of the amounts in accumulated other comprehensive income amortized and recognized as a component of net periodic benefit cost, net of tax	(in millions) 2017 2016 Net loss / (gain) $ ) $ Amortization of net (loss) gain ) ) Amortization of prior services cost (credit) — ​ ​ ​ ​ ​ ​ ​ ​ Total amortization expenses $ ) $ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​
Scheduled maturities of the benefits expected to be paid in each of the next five years, and thereafter	Years Expected (in millions) 2018 $ 2019 2020 2021 2022 2023 to 2025 ​ ​ ​ ​ ​ Total $ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​
Post-retirement Health care plans
Components of net periodic benefit costs
Schedule of the components of net periodic benefit costs	Years ended (in millions) 2017 2016 2015 Interest cost $ $ $ Amortization of prior service cost/ (credit) ) ) ) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Net periodic benefit cost $ $ $ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​
Schedule of changes in the benefit obligation and plan assets, the funded status of the plans and the amount recognized in balance sheet and accumulated other comprehensive income	As of (in millions) 2017 2016 Change in benefit obligation: Projected benefit obligation at beginning of year $ $ Interest cost Actuarial loss/ (gain)—claims cost ) — Benefits paid ) ) Actuarial (gain)/loss ) Inflation adjustment ) ​ ​ ​ ​ ​ ​ ​ ​ Projected benefit obligation at end of year $ $ ​ ​ ​ ​ ​ ​ ​ ​ Change in plan assets: Fair value of plan assets at beginning of year $ — $ — Employer contributions Benefits paid ) ) ​ ​ ​ ​ ​ ​ ​ ​ Fair value of plan assets at end of year $ — $ — ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Funded status at end of year: $ $ ) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ASC-715 amounts recognized in statement of financial position consists of: Current liabilities $ ) $ ) Non-current liabilities ) ) ​ ​ ​ ​ ​ ​ ​ ​ Total $ ) $ ) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ASC-715 amounts recognized in accumulated other comprehensive income consists of: Net loss (gain) $ ) $ ) Total (net of income taxes of $1.7 million and $1.4 million in 2017 and 2016, respectively) $ ) $ ) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​
Schedule of changes in accumulated other comprehensive income	As of (in millions) 2017 2016 Reconciliation of accumulated other comprehensive income: Accumulated other comprehensive income at beginning of plan year $ ) $ ) Net loss/(gain) occurring during the year ) Net loss/(gain) amortized during the year Currency exchange rate adjustment ) ​ ​ ​ ​ ​ ​ ​ ​ Net adjustment to accumulated other comprehensive income (net of income taxes of $0.3 million and $1.9 million in 2017 and 2016, respectively) ) ​ ​ ​ ​ ​ ​ ​ ​ Accumulated other comprehensive income at end of plan year $ ) $ ) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​
Summary of the amounts in accumulated other comprehensive income amortized and recognized as a component of net periodic benefit cost, net of tax	At (in millions) 2017 2016 Net loss / (gain) $ ) $ Amortization of net (loss) gain ​ ​ ​ ​ ​ ​ ​ ​ Total amortization expenses $ ) $ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​
Scheduled maturities of the benefits expected to be paid in each of the next five years, and thereafter	Year Expected (in millions) 2018 $ 2019 2020 2021 2022 2023 to 2027 ​ ​ ​ ​ ​ Total $ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​
Expatriate Plan | Post retirement defined benefit plans
Components of net periodic benefit costs
Schedule of assumptions used to determine the pension obligations and other post-retirement benefits	Years ended (in millions) 2017 2016 2015 Service cost $ $ $ Interest cost Expected return on plan assets ) ) ) Amortization of transition assets, net Amortization of net actuarial loss — — ) Settlement / Curtailment ) — Amortization of net loss/(gain) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Net periodic benefit cost $ ) $ ) $ ) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​
Expatriate Plan | Post-retirement Health care plans
Components of net periodic benefit costs
Schedule of assumptions used to determine the pension obligations and other post-retirement benefits	Expatriate Plan 2017 2016 2015 Discount rate % % % Expected long-term rate of return on plan asset % % % Rate of increase in future compensation level N/A N/A N/A
Mexican Health Plan | Post retirement defined benefit plans
Components of net periodic benefit costs
Schedule of asset mix of the investment portfolio	2017 2016 Asset category: Equity securities % % Treasury bills % % ​ ​ ​ ​ ​ ​ ​ ​ % % ​ ​ ​ ​ ​ ​ ​ ​
Mexican Health Plan | Post-retirement Health care plans
Components of net periodic benefit costs
Schedule of assumptions used to determine the pension obligations and other post-retirement benefits	Mexican Plan(*) 2017 2016 2015 Discount rate % % % Expected long-term rate of return on plan asset % % % Rate of increase in future compensation level % % % (*) These rates are based on Mexican pesos as pension obligations are denominated in pesos.
Schedule of effects of one percentage-point change in assumed other benefits cost trend rates	One Percentage (in millions) Increase Decrease Effect on total service and interest cost components $ $ Effect on the post-retirement benefit obligation $ $

COMMITMENTS AND CONTINGENCIES_

COMMITMENTS AND CONTINGENCIES: (Tables)	12 Months Ended
	Dec. 31, 2017
COMMITMENTS AND CONTINGENCIES:
Schedule of environmental capital investments	Environmental capital investments in years 2017, 2016 and 2015, were as follows (in millions): 2017 2016 2015 Peruvian operations $ $ $ Mexican operations ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Total $ $ $ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​

STOCKHOLDERS' EQUITY (Tables)

STOCKHOLDERS' EQUITY (Tables)	12 Months Ended
	Dec. 31, 2017
Share based Compensation Plan
Schedule of activity in treasury stock	Activity in treasury stock in the years 2017 and 2016 was as follows (in millions): 2017 2016 Southern Copper common shares Balance as of January 1, $ $ Purchase of shares — Used for corporate purposes ) ) ​ ​ ​ ​ ​ ​ ​ ​ Balance as of December 31, ​ ​ ​ ​ ​ ​ ​ ​ Parent Company (Grupo Mexico) common shares Balance as of January 1, Other activity, including dividend, interest and foreign currency transaction effect ​ ​ ​ ​ ​ ​ ​ ​ Balance as of December 31, ​ ​ ​ ​ ​ ​ ​ ​ Treasury stock balance as of December 31, $ $ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​
Schedule of share repurchase program activity	Maximum Period Total Number of Total Number Average Total Cost From To 2008 2012 $ 2013: 2014: 2015: 2016: Total purchased $ $ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ (1) NYSE closing price of SCC common shares at December 31, 2017.
Schedule of activity in Directors' Stock Award Plan	2017 2016 Total SCC shares reserved for the plan ​ ​ ​ ​ ​ ​ ​ ​ Total shares granted at January 1, ) ) Granted in the period ) ) ​ ​ ​ ​ ​ ​ ​ ​ Total shares granted at December 31, ) ) ​ ​ ​ ​ ​ ​ ​ ​ Remaining shares reserved ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​
Employee Stock Purchase 2010 Plan
Share based Compensation Plan
Schedule of stock based compensation expense and unrecognized compensation expense	The stock based compensation expense for the years ended December 31, 2017, 2016 and 2015 and the remaining balance of the unrecognized compensation expense under this plan were as follows (in millions): 2017 2016 2015 Stock based compensation expense $ $ $ Unrecognized compensation expense $ $ $
Schedule of stock award activity	Shares Unit Weighted Average Outstanding shares at January 1, 2017 $ Granted — — Exercised ) Forfeited — — ​ ​ ​ ​ ​ ​ ​ ​ Outstanding shares at December 31, 2017 $ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Outstanding shares at January 1, 2016 $ Granted — — Exercised ) Forfeited — — ​ ​ ​ ​ ​ ​ ​ ​ Outstanding shares at December 31, 2016 $ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​
Employee Stock Purchase 2015 Plan
Share based Compensation Plan
Schedule of stock based compensation expense and unrecognized compensation expense	The stock based compensation expense for the years ended December 31, 2017, 2016 and 2015 and the unrecognized compensation expense under this plan were as follows (in millions): 2017 2016 2015 Stock based compensation expense $ $ $ Unrecognized compensation expense $ $ $
Schedule of stock award activity	Shares Unit Weighted Average Outstanding shares at January 1, 2017 $ Granted — Exercised ) $ Forfeited — ​ ​ ​ ​ ​ ​ ​ ​ Outstanding shares at December 31, 2017 $ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Outstanding shares at January 1, 2016 $ Granted — — Exercised ) $ Forfeited — — ​ ​ ​ ​ ​ ​ ​ ​ Outstanding shares at December 31, 2016 $ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​

FAIR VALUE MEASUREMENT_ (Tables

FAIR VALUE MEASUREMENT: (Tables)	12 Months Ended
	Dec. 31, 2017
FAIR VALUE MEASUREMENT:
Schedule of carrying amount and estimated fair values of the Company's financial instruments	Financial instruments are not included in the following table that provides information about the carrying amounts and estimated fair values of other financial instruments that are not measured at fair value in the consolidated balance sheet as of December 31, 2017 and December 31, 2016 (in millions): At December 31, 2017 At December 31, 2016 Carrying Value Fair Value Carrying Value Fair Value Liabilities: Long-term debt level 1 Long-term debt level 2 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Total long-term debt $ $ $ $
Schedule of fair values of assets and liabilities measured at fair value on a recurring basis	Fair values of assets and liabilities measured at fair value on a recurring basis were calculated as of December 31, 2017 and 2016, as follows (in millions): Fair Value at Measurement Date Using: Description Fair Value Quoted prices in Significant Significant Assets: Short term investment: —Trading securities $ $ — $ — —Available-for-sale debt securities: Corporate bonds — $ — Asset backed securities — — Mortgage backed securities — — Accounts receivable: —Embedded derivatives—Not classified as hedges: Provisionally priced sales: Copper — — Molybdenum — — ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Total $ $ $ $ — ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Fair Value at Measurement Date Using: Description Fair Value Quoted prices in Significant Significant Assets: Short term investment: —Trading securities $ $ — $ — —Available-for-sale debt securities: Corporate bonds — — — — Asset backed securities — — — — Mortgage backed securities — $ — Accounts receivable: —Embedded derivatives—Not classified as hedges: Provisionally priced sales: Copper — — Molybdenum — — ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Total $ $ $ $ — ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​

CONCENTRATION OF RISK_ (Tables)

CONCENTRATION OF RISK: (Tables)	12 Months Ended
	Dec. 31, 2017
CONCENTRATION OF RISK:
Schedule of concentration risk for cash equivalents and short- term investments	% in one institution Country $ in % of total of country of total cash United States $ % % % Switzerland % % % Peru % % % Mexico % % % ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Total cash and short-term investment $ % ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ (1) 94.9% of the Company's cash is in U.S. dollars.
Schedule of company's largest customers as percentage of accounts receivable and total sales	2017 2016 2015 Accounts receivable trade as of December 31, Five largest customers % % % Largest customer % % % Total sales in year Five largest customers % % % Largest customer % % %

RELATED PARTY TRANSACTIONS_ (Ta

RELATED PARTY TRANSACTIONS: (Tables)	12 Months Ended
	Dec. 31, 2017
RELATED PARTY TRANSACTIONS:
Schedule of receivable and payable balances with related parties	Receivable and payable balances with related parties are shown below (in millions): At 2017 2016 Related parties receivable current: Grupo Mexico and affiliates: Mexico Generadora de Energia S. de R.L. ("MGE") $ $ Asarco LLC Grupo Mexico Compañia Perforadora Mexico S.A.P.I. de C.V. and affiliates Mexico Proyectos y Desarrollos, S.A. de C.V. and affiliates Operadora de Generadoras de Energia Mexico S.A. de C.V. — Related to the controlling group: Operadora de Cinemas S.A. de C.V. Boutique Bowling de Mexico S.A. de C.V. ​ ​ ​ ​ ​ ​ ​ ​ $ $ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Related parties payable: Grupo Mexico and affiliates: MGE $ $ Asarco LLC Mexico Proyectos y Desarrollos S.A. de C.V. and affiliates Ferrocarril Mexicano S.A. de C.V. Eolica El Retiro, S.A.P.I. de C.V. Grupo Mexico Related to the controlling group: Operadora de Cinemas S.A. de C.V. Boutique Bowling de Mexico S.A. de C.V. Mexico Transportes Aereos S.A. de C.V. ("Mextransport") Related to SCC executive officers: Breaker, S.A. de C.V. and affiliates ("Breaker") — ​ ​ ​ ​ ​ ​ ​ ​ $ $ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​
Grupo Mexico and affiliates
RELATED PARTY TRANSACTIONS:
Schedule of purchase and sales activities with related parties	The following table summarize the purchase and sale activities with Grupo Mexico and its affiliates in 2017, 2016 and 2015 (in millions): 2017 2016 2015 Purchase activity Asarco LLC $ $ $ Compañia Perforadora Mexico S.A.P.I. de C.V. and affiliates — Eolica El Retiro, S.A.P.I. de C.V. Ferrocarril Mexicano, S.A. de C.V. Grupo Mexico Mexico Proyectos y Desarrollos S.A. de C.V. and affiliates MGE ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Total purchases $ $ $ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Sales activity Asarco LLC $ $ $ Compañia Perforadora Mexico S.A.P.I. de C.V. and affiliates Grupo Mexico Mexico Proyectos y Desarrollos S.A. de C.V. and affiliates — Operadora de Generadoras de Energia Mexico S.A. de C.V — — MGE ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Total sales $ $ $ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​
Related to the controlling group
RELATED PARTY TRANSACTIONS:
Schedule of purchase and sales activities with related parties	The following table summarizes the purchase and sales activities with other Larrea family companies in 2017, 2016 and 2015 (in millions): 2017 2016 2015 Purchase activity Boutique Bowling de Mexico S.A. de C.V. $ $ $ Mextransport Operadora de Cinemas S.A. de C.V. ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Total purchases $ $ $ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Sales activity Boutique Bowling de Mexico S.A. de C.V. $ $ $ Mextransport Operadora de Cinemas S.A. de C.V. ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Total sales $ $ $ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​
Related to SCC executive officers
RELATED PARTY TRANSACTIONS:
Schedule of purchase activity with related parties	The following table summarizes the purchase activities with companies with relationships to SCC executive officers in 2017, 2016 and 2015 (in millions): 2017 2016 2015 Breaker $ — $ $ Higher Technology S.A.C. — Servicios y Fabricaciones Mecanicas S.A.C. Sempertrans — — ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Total purchased $ $ $ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​

SEGMENT AND RELATED INFORMATI45

SEGMENT AND RELATED INFORMATION: (Tables)	12 Months Ended
	Dec. 31, 2017
SEGMENT AND RELATED INFORMATION:
Schedule of financial information relating to Company's segments	Year Ended December 31, 2017 (in millions) Mexican Mexican Peruvian Corporate, other Consolidated Net sales outside of segments $ $ $ $ — $ Intersegment sales — — ) — Cost of sales (exclusive of depreciation, amortization and depletion) ) Selling, general and administrative Depreciation, amortization and depletion Exploration Environmental remediation ) — — — ) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Operating income $ $ $ $ ) Less: Interest, net ) Other income (expense) ) Income taxes ) Equity earnings of affiliate Non-controlling interest ) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Net income attributable to SCC $ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Capital investment $ $ $ $ $ Property and mine development, net $ $ $ $ $ Total assets $ $ $ $ $ Year Ended December 31, 2016 (in millions) Mexican Mexican Peruvian Corporate, other Consolidated Net sales outside of segments $ $ $ $ — $ Intersegment sales — — ) — Cost of sales (exclusive of depreciation, amortization and depletion) ) Selling, general and administrative Depreciation, amortization and depletion Exploration Environmental remediation — — — — — ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Operating income $ $ $ $ ) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Less: Interest, net ) Other income (expense) ) Income taxes ) Equity earnings of affiliate Non-controlling interest ) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Net income attributable to SCC $ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Capital investment $ $ $ $ $ Property and mine development, net $ $ $ $ $ Total assets $ $ $ $ $ Year Ended December 31, 2015 (in millions) Mexican Mexican Peruvian Corporate, other Consolidated Net sales outside of segments $ $ $ $ — $ Intersegment sales — — ) — Cost of sales (exclusive of depreciation, amortization and depletion) ) Selling, general and administrative Depreciation, amortization and depletion ) Exploration Environmental remediation — — — ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Operating income $ $ $ $ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Less: Interest, net ) Other income (expense) ) Income taxes ) Equity earnings of affiliate Non-controlling interest ) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Net income attributable to SCC $ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Capital investment(*) $ $ $ $ $ Property and mine development, net $ $ $ $ $ Total assets $ $ $ $ $ (*) Corporate, other and eliminations includes $100.4 million purchase of the El Pilar mining property acquisition.
Schedule of sales value per segment	Year Ended December 31, 2017 (in millions) Mexican Mexican Peruvian Corporate, Other & Total Copper $ $ $ $ ) $ Molybdenum — — Silver ) Zinc — — ) Other ) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Total $ $ $ $ ) $ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended December 31, 2016 (in millions) Mexican Mexican Peruvian Corporate, Other & Total Copper $ $ $ $ ) $ Molybdenum — — Silver ) Zinc — — — Other ) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Total $ $ $ $ ) $ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended December 31, 2015 (in millions) Mexican Mexican Peruvian Corporate, Other & Total Copper $ $ $ $ ) $ Molybdenum — — Silver ) Zinc — — — Other ) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Total $ $ $ $ ) $ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​
Schedule of net sales by countries	The geographic breakdown of the Company's sales for the three years ended December 31, 2017 were as follows (in millions): 2017 2016 2015 The Americas: Mexico $ $ $ United States Peru Brazil Chile Other American countries Europe: Switzerland Italy Other European countries Asia: Singapore Japan Other Asian countries ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Total $ $ $ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​
Schedule of provisionally priced copper and molybdenum sales outstanding	Sales volume Priced at Month of settlement Copper January through March 2018 Molybdenum January through March 2018
Schedule of provisional sales price adjustments included in accounts receivable and net sales	Provisional sales price adjustments included in accounts receivable and net sales were as follows at December, 31 (in millions): At 2017 2016 Copper $ $ Molybdenum ) ​ ​ ​ ​ ​ ​ ​ ​ Total $ $ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​

QUARTERLY DATA (unaudited) (Tab

QUARTERLY DATA (unaudited) (Tables)	12 Months Ended
	Dec. 31, 2017
QUARTERLY DATA (unaudited)
Schedule of quarterly financial data	2017 (in millions, except per share data) 1 st 2 nd 3 rd 4 th Year Net sales $ $ $ $ $ Gross profit(1) $ $ $ $ $ Operating income $ $ $ $ $ Net income (loss) $ $ $ $ ) $ Net income (loss) attributable to SCC $ $ $ $ ) $ Per share amounts attributable to SCC: Net earnings basic and diluted $ $ $ $ ) $ Dividend per share $ $ $ $ $ 2016 1 st 2 nd 3 rd 4 th Year Net sales $ $ $ $ $ Gross profit(1) $ $ $ $ $ Operating income $ $ $ $ $ Net income $ $ $ $ $ Net income attributable to SCC $ $ $ $ $ Per share amounts attributable to SCC: Net earnings basic and diluted $ $ $ $ $ Dividend per share $ $ $ $ $ (1) Gross profit is the result of net sales less cost of sales (excluding depreciation, amortization and depletion) and less depreciation, amortization and depletion.

DESCRIPTION OF THE BUSINESS_ (D

DESCRIPTION OF THE BUSINESS: (Details)	Dec. 31, 2017	Dec. 31, 2016
DESCRIPTION OF THE BUSINESS:
Percentage of ownership interest held by the parent company	88.90%	88.90%

SUMMARY OF SIGNIFICANT ACCOUN48

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES: (Details) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017USD ($)segmentitem$ / lb	Dec. 31, 2016$ / lb	Dec. 31, 2015$ / lb
Significant Accounting Policies
Increase in total reserves at a property to qualify as a major expansion (as a percent)		10.00%
Period considered for calculation of average metal price		3 years
Current price of copper (in dollars per pound) | $ / lb		2.50	2.61	2.99
U.S. statutory rate (as a percent)		35.00%	35.00%	35.00%
Impairment in the carrying value of long-term assets | $		$ 0
Number of years of average prices for copper and molybdenum used for impairment analysis		3 years
Number of reportable segments | segment		3
Forecast
Significant Accounting Policies
U.S. statutory rate (as a percent)	21.00%
Minimum
Financial information related to segments
Estimated useful lives of buildings and equipment		5 years
Maximum
Financial information related to segments
Maximum period after shipping within which pricing is based by customer contracts in most cases		3 months
Estimated useful lives of buildings and equipment		40 years
Peruvian Operations
Financial information related to segments
Number of open-pit copper mines		2
Mexican IMMSA Unit
Financial information related to segments
Number of underground poly metal mines		5

SHORT-TERM INVESTMENTS_ (Detail

SHORT-TERM INVESTMENTS: (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016
Short-term investment:
Trading securities	$ 49.5	$ 49.2
Weighted average interest rate (as a percent)	1.80%	2.20%
Available-for-sale	$ 1	$ 2.1
Weighted average interest rate (as a percent)	0.70%	0.78%
Total	$ 50.5	$ 51.3
Trading :
Interest earned	0.7	1.5
Unrealized gain (loss) at the end of the period	0.1	0.4
Available-for-sale:
Investment redeemed	1.1	1.2
Contractual maturities of available-for-sale debt securities
Due after 10 years	1	2.1
Total debt securities	1	2.1
Maximum
Available-for-sale:
Interest earned	$ 0.1	$ 0.1

INVENTORIES_ (Details)

INVENTORIES: (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Metals at average cost:
Finished goods	$ 48.8	$ 130.5
Work-in-process	308	231.6
Ore stockpiles on leach pads	320.9	310.9
Supplies at average cost	364.2	337.4
Total current inventory	1,041.9	1,010.4
Inventory, long-term:
Ore stockpiles on leach pads	977.4	806.9
Total leaching costs added as long-term inventory of ore stockpiles in leach pads	513.9	439	$ 506.9
Long-term leaching inventories recognized as cost of sales	$ 333.5	$ 316.6	$ 274.1

PROPERTY_ (Details)

PROPERTY: (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Property
Total property	$ 15,424.2	$ 14,473.3
Accumulated depreciation, amortization and depletion	(6,324.6)	(5,706.8)
Total property and mine development, net	9,099.6	8,766.5	$ 8,262.8
Depreciation and depletion expense	665.2	639.1	$ 503.6
Buildings and equipment
Property
Total property	12,552.8	12,177.1
Construction in progress
Property
Total property	2,301.9	1,811.8
Mine development
Property
Total property	267.9	259.1
Mineral assets
Property
Total property	83.2	83.2
Land, other than mineral
Property
Total property	$ 218.4	$ 142.1

INTANGIBLE ASSETS_ - Other (Det

INTANGIBLE ASSETS: - Other (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Intangible assets
Intangible assets excluding goodwill, gross	$ 190	$ 185.8
Accumulated amortization	(79.4)	(73.5)
Goodwill	41.9	41.9
Intangible assets, net	152.5	154.2
Amortization expense:
Amortization expense	5.9	8	$ 7.1
Estimated amortization expense:
2,018	5.6
2,019	5.5
2,020	5.6
2,021	5.5
2,022	3.9
Total 2018-2022	26.1
Average annual	5.2
Mining concessions
Intangible assets
Intangible assets excluding goodwill, gross	121.2	121.2
Accumulated amortization	(36.6)	(35.6)
Mine engineering and development studies
Intangible assets
Intangible assets excluding goodwill, gross	19.8	19.8
Accumulated amortization	(15.3)	(14.8)
Software
Intangible assets
Intangible assets excluding goodwill, gross	49	44.8
Accumulated amortization	$ (27.5)	$ (23.1)

INTANGIBLE ASSETS_ Goodwill (De

INTANGIBLE ASSETS: Goodwill (Details) - USD ($) $ in Millions	Dec. 31, 2017	Dec. 31, 2016
Intangible assets
Goodwill	$ 41.9	$ 41.9
Buenavista del Cobre, S.A. de C.V
Intangible assets
Goodwill	17
El Pilar
Intangible assets
Goodwill	$ 24.9

INCOME TAXES_ - Tax Cuts and Jo

INCOME TAXES: - Tax Cuts and Jobs Act (Details) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017USD ($)item	Dec. 31, 2016	Dec. 31, 2015	Mar. 31, 2009
Income Taxes
Percentage of ownership interest held by the parent company		88.90%	88.90%
U.S. statutory rate (as a percent)		35.00%	35.00%	35.00%
Non-cash tax expense for estimated tax effect | $		$ 785.9
Number of new taxes become effective | item		2
Forecast
Income Taxes
U.S. statutory rate (as a percent)	21.00%
Minimum | Beginning in 2018
Income Taxes
BEAT tax rate (as a percent)		5.00%
Minimum | After 2025
Income Taxes
BEAT tax rate (as a percent)		12.50%
AMC | Minimum
Income Taxes
Percentage of ownership interest held by the parent company					80.00%

INCOME TAXES_ - Provision (Deta

INCOME TAXES: - Provision (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
U.S. federal and state:
Deferred	$ 686.2	$ (109.4)	$ (143)
Uncertain tax positions	16.2	20.3	80
Provision for income taxes	702.4	(89.1)	(63)
Foreign (Peru and Mexico):
Current	951.7	625	620.4
Deferred	(60.7)	(34.8)	(92.5)
Provision for income taxes	891	590.2	527.9
Total provision for income taxes	1,593.4	501.1	464.9
Earnings by location:
U.S.	(1.5)	(1.9)	(2.1)
Peru	284.6	(85.7)	213.2
Mexico	2,019.6	1,343.6	978.1
Foreign	2,304.2	1,257.9	1,191.3
Income before income taxes	$ 2,302.7	$ 1,256	$ 1,189.2

INCOME TAXES_ - Effective tax r

INCOME TAXES: - Effective tax rate (Details) - item	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Reconciliation of the statutory income tax rate to the effective tax rate
Expected tax at U.S. statutory rate (as a percent)	35.00%	35.00%	35.00%
Foreign tax at other than statutory rate, net of foreign tax credit benefit (as a percent)	0.60%	2.00%	3.60%
Percentage depletion (as a percent)	(2.90%)	(2.70%)	(5.90%)
Other permanent differences (as a percent)	5.20%		0.70%
Valuation allowance on US deferred tax assets, foreign tax credits and US tax effect on Peruvian deferred	26.90%
Decrease in US deferred tax asset due to tax rate changes	4.80%
US one time transition tax on accumulated foreign earnings	2.40%
Increase (decrease) in unrecognized tax benefits for uncertain tax positions (as a percent)	0.70%	0.20%	6.70%
Repatriated foreign earnings (as a percent)	(2.00%)	3.60%
Amounts (over) / under provided in prior years	(0.10%)	(0.50%)	(2.20%)
Other (as a percent)	(1.40%)	2.30%	1.20%
Effective income tax rate	69.20%	39.90%	39.10%
Number of jurisdictions where company files income tax returns	3
Duration for which statutory tax rates for Peru and Mexico are considered to determine effective tax rate	3 years
Mexico
Reconciliation of the statutory income tax rate to the effective tax rate
Expected tax at U.S. statutory rate (as a percent)	30.00%	30.00%	30.00%
Peru
Reconciliation of the statutory income tax rate to the effective tax rate
Expected tax at U.S. statutory rate (as a percent)	29.50%	28.00%	28.00%

INCOME TAXES_ - Tax assets and

INCOME TAXES: - Tax assets and liabilities (Details) - USD ($) $ in Millions	Dec. 31, 2017	Dec. 31, 2016
Assets:
Inventories	$ 47	$ 27.9
Capitalized exploration expenses	9.5	17.5
U.S. foreign tax credit carryforward, net of FIN 48 liability	280.2	284.2
U.S. tax effect of Peruvian deferred tax liability	174.1	162.6
Property, plant and equipment		1.2
Reserves	152.6	108.9
Mexican tax on consolidated dividends	14.5	13.6
Prepaids		11.1
Valuation allowance on US deferred tax assets, foreign tax credits and US tax effect on Peruvian deferred	(619.6)
Other	9.4	29.7
Total deferred tax assets	67.7	656.7
Liabilities:
Property, plant and equipment	(130.3)
Deferred charges	(16.9)	(35.4)
Unremitted foreign earnings		(45.7)
Other	(1.2)	(10.9)
Total deferred tax liabilities	(148.4)	(92)
Total net deferred tax (liabilities) / assets		$ 564.7
Total deferred tax (liabilities) / assets	$ (80.7)

INCOME TAXES_ - Carryforward (D

INCOME TAXES: - Carryforward (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Foreign tax credits
Other U.S. tax credits		$ 0
Unrecognized Tax Benefits		$ 214.5	$ 304	$ 400	$ 319.4
Income Tax Rate (as a percent)		35.00%	35.00%	35.00%
Forecast
Foreign tax credits
Income Tax Rate (as a percent)	21.00%
United States | Forecast
Foreign tax credits
Income Tax Rate (as a percent)	21.00%
Mexico
Foreign tax credits
Unrecognized Tax Benefits		$ 0
Income Tax Rate (as a percent)		30.00%	30.00%	30.00%
Mexico | Forecast | Minimum
Foreign tax credits
Income Tax Rate (as a percent)	30.00%
Peru
Foreign tax credits
Unrecognized Tax Benefits		$ 0
Income Tax Rate (as a percent)		29.50%	28.00%	28.00%
Peru | Forecast | Minimum
Foreign tax credits
Income Tax Rate (as a percent)	30.00%
Foreign
Foreign tax credits
Tax credits carryback period		1 year
Tax credits carryforward period		10 years
Increase in foreign tax credits		$ 15.9
Unrecognized Tax Benefits		205.7
Foreign tax credit carryforward		485.8
Foreign tax credit carryforward net of unrecognized tax benefit		280.2
2022 | Foreign
Foreign tax credits
Foreign tax credit carryforward		20.3
2023 | Foreign
Foreign tax credits
Foreign tax credit carryforward		69.2
2024 | Foreign
Foreign tax credits
Foreign tax credit carryforward		102
2025 | Foreign
Foreign tax credits
Foreign tax credit carryforward		189.5
2026 | Foreign
Foreign tax credits
Foreign tax credit carryforward		$ 104.8

INCOME TAXES_ - Other (Details)

INCOME TAXES: - Other (Details) PEN in Millions, $ in Millions	12 Months Ended
	Dec. 31, 2017PEN	Dec. 31, 2017USD ($)item	Dec. 31, 2016PEN	Dec. 31, 2016USD ($)	Dec. 31, 2015PEN	Dec. 31, 2015USD ($)	Oct. 31, 2017	Sep. 30, 2017
Income Taxes
Cash, cash equivalents, restricted cash and short-term investments		$ 1,055.3
Estimated tax on foreign earnings and profit		8,900
U.S. federal income tax		0
State income tax		0
Provisional tax amount		$ 181.1
Income Tax Rate (as a percent)	35.00%	35.00%	35.00%	35.00%	35.00%	35.00%
Withholding tax rate on interest							0.46%	0.58%
Changes in unrecognized tax benefits
Unrecognized tax benefits, opening balance		$ 304		$ 400		$ 319.4
Gross increases - tax positions in prior period				3.9		36.3
Gross decreases - tax positions in prior period		(89.5)
Gross increases - current-period tax positions				23.3		44.3
Decreases related to settlements with taxing authorities				(123.2)
Increase (decrease) in unrecognized tax benefits		(89.5)		(96)		80.6
Unrecognized tax benefits, ending balance		214.5		304		$ 400
Amount of unrecognized tax benefits that, if recognized, would affect the effective tax rate		214.5		304
Accrued interest and penalties included in liability for uncertain tax positions		$ 1.9		1.9
Number of major tax jurisdictions | item		3
Minera Mexico
Income Taxes
Earnings available for dividends to United States		$ 555.5		$ 470.5
Foreign subsidiaries
Income Taxes
Cash, cash equivalents, restricted cash and short-term investments		517.7
Foreign
Changes in unrecognized tax benefits
Unrecognized tax benefits, opening balance
Unrecognized tax benefits, ending balance		$ 205.7
Peru
Income Taxes
Income Tax Rate (as a percent)	29.50%	29.50%	28.00%	28.00%	28.00%	28.00%
Royalty charge assessed as a percentage of net sales	1.00%	1.00%
Increase in royalty tax rate for each 5% increase up to 12% increase in operating income margin (as a percent)	0.75%	0.75%
Royalty charges | PEN	PEN 23.4		PEN 16.8		PEN 22.9
Provision for royalty tax		$ 2.5		$ 0		$ 2.7
Peruvian special mining tax		23.3		$ 10.8		$ 18.1
Changes in unrecognized tax benefits
Unrecognized tax benefits, opening balance
Unrecognized tax benefits, ending balance		$ 0
Peru | 2015-2016
Income Taxes
Income Tax Rate (as a percent)	28.00%	28.00%
Dividend Tax Rate (as a percent )	6.80%	6.80%
Peru | 2017 and later
Income Taxes
Income Tax Rate (as a percent)	29.50%	29.50%
Dividend Tax Rate (as a percent )	5.00%	5.00%
Peru | Minimum
Income Taxes
Mining royalty tax (as a percent)	1.00%	1.00%
Increment in operating income margin for royalty tax (as a percent)	5.00%	5.00%
Special mine tax (as a percent)	2.00%	2.00%
Peru | Maximum
Income Taxes
Mining royalty tax (as a percent)	12.00%	12.00%
Increment in operating income margin for royalty tax (as a percent)	10.00%	10.00%
Special mine tax (as a percent)	8.40%	8.40%
United States | Minimum | Minera Mexico
Income Taxes
Excess of financial reporting over tax basis for stock in subsidiary		$ 6,700
Mexico
Income Taxes
Income Tax Rate (as a percent)	30.00%	30.00%	30.00%	30.00%	30.00%	30.00%
Mining royalty tax (as a percent)	7.50%	7.50%
Mining royalty amount on earnings before taxes		$ 87.8
Additional royalty tax over gross income from sales of gold, silver and platinum (as a percent)	0.50%	0.50%
Additional royalty over sales revenue from gold, silver and platinum		$ 0.8
Income tax payable due to tax consolidation		0.3
Changes in unrecognized tax benefits
Unrecognized tax benefits, opening balance
Unrecognized tax benefits, ending balance		$ 0

WORKERS' PARTICIPATION_ (Detail

WORKERS' PARTICIPATION: (Details) $ in Millions	12 Months Ended
	Dec. 31, 2017USD ($)item	Dec. 31, 2016USD ($)	Dec. 31, 2015USD ($)
Statutory workers' participation
Current	$ 192.7	$ 131.8	$ 140.8
Deferred	6.6	(13.4)	(19.8)
Workers' participation expense (in USD)	$ 199.3	$ 118.4	$ 121
Peru
Statutory workers' participation
Provision for workers' participation as a percentage of pre-tax earnings	8.00%
Number of months for which an individual worker's salary is capped for consideration of annual individual worker participation	18 months
Maximum taxable units contributed by employer to benefit fund (in Peruvian taxable units) | item	2,200
Maximum employer contribution to benefit fund (in USD)	$ 2.7
Mexico
Statutory workers' participation
Provision for workers' participation as a percentage of pre-tax earnings	10.00%

ASSET RETIREMENT OBLIGATION_ (D

ASSET RETIREMENT OBLIGATION: (Details) $ in Millions	12 Months Ended
	Dec. 31, 2017USD ($)item	Dec. 31, 2016USD ($)	Dec. 31, 2015USD ($)
ASSET RETIREMENT OBLIGATION:
Period after which successive reviews are required by the law (in years)	5 years
Accepted value of the Lima office building	$ 36.9
Cumulative guarantee amount	$ 32.3
Number of units with future closure costs recognized as an asset retirement obligation | item	3
Environmental remediation	$ (10.2)		$ 45
Asset retirement obligation activity
Balance at the beginning of the year	216.5	$ 190.9
Changes in estimates	(11.6)
Additions		10.5
Closure payments	(0.3)	(2)
Accretion expense	17.9	17.1
Balance at the end of the year	222.5	216.5	190.9
Mexico
ASSET RETIREMENT OBLIGATION:
Plant demolition and soil remediation budgeted cost	$ 66.2
Toquepala Concentrator Expansion
Asset retirement obligation activity
Additions			$ 12.5
Buenavista Project
Asset retirement obligation activity
Additions		$ 9.5

FINANCING_ - Debt instruments (

FINANCING: - Debt instruments (Details) $ in Millions	Apr. 20, 2015USD ($)tranche	Dec. 31, 2017USD ($)itemgrade	Nov. 30, 2012USD ($)item	Dec. 31, 2016USD ($)
FINANCING
Face amount		$ 6,125	$ 4,200	$ 6,125
Issuance discount		(60.5)		(62.2)
Issuance costs	$ (11.8)	(33.6)		(34.8)
Carrying value		5,957.1		5,954.2
Total long term debt		$ 5,957.1		5,954.2
Number of tranches | tranche	2
Underwriters discount	$ 20.2
Number of times for which senior unsecured notes were issued | item			6
Percentage of principal amount at which notes may be required to be repurchased in event of change of control in the entity		101.00%
Minimum
FINANCING
Number of decreased gradations that could cause a change of control triggering event | grade		1
5.375% Senior unsecured notes due 2020
FINANCING
Face amount		$ 400		400
Issuance discount		(0.6)		(0.8)
Issuance costs		(0.6)		(0.9)
Carrying value		$ 398.8		$ 398.3
Interest rate (as a percent)		5.375%		5.375%
3.500% Senior unsecured notes due 2022
FINANCING
Face amount		$ 300		$ 300
Issuance discount		(0.5)		(0.7)
Issuance costs		(0.8)		(0.9)
Carrying value		$ 298.7		$ 298.4
Interest rate (as a percent)		3.50%		3.50%
3.875% Senior unsecured notes due 2025
FINANCING
Face amount	$ 500	$ 500		$ 500
Issuance discount		(2.1)		(2.3)
Issuance costs		(2)		(2.2)
Carrying value		$ 495.9		$ 495.5
Interest rate (as a percent)	3.875%	3.875%		3.875%
9.250% Yankee Bonds due 2028
FINANCING
Face amount		$ 125		$ 125
Carrying value		$ 51.2		$ 51.2
Interest rate (as a percent)		9.25%		9.25%
9.250% Yankee Bonds due 2028 | Minera Mexico | Minimum
FINANCING
Ratio of EBITDA to interest expense | item		2.5
7.500% Senior unsecured notes due 2035
FINANCING
Face amount		$ 1,000		$ 1,000
Issuance discount		(13.2)		(13.6)
Issuance costs		(8.8)		(8.9)
Carrying value		$ 978		$ 977.5
Interest rate (as a percent)		7.50%		7.50%
6.750% Senior unsecured notes due 2040
FINANCING
Face amount		$ 1,100		$ 1,100
Issuance discount		(7.4)		(7.5)
Issuance costs		(5.9)		(6.1)
Carrying value		$ 1,086.7		$ 1,086.4
Interest rate (as a percent)		6.75%		6.75%
5.250% Senior unsecured notes due 2042
FINANCING
Face amount		$ 1,200		$ 1,200
Issuance discount		(19.8)		(20.2)
Issuance costs		(6.6)		(6.7)
Carrying value		$ 1,173.6		$ 1,173.1
Interest rate (as a percent)		5.25%		5.25%
5.875% Senior unsecured notes due 2045
FINANCING
Face amount	$ 1,500	$ 1,500		$ 1,500
Issuance discount		(16.9)		(17.1)
Issuance costs		(8.9)		(9.1)
Carrying value		$ 1,474.2		$ 1,473.8
Interest rate (as a percent)	5.875%	5.875%		5.875%
Fixed-rate senior unsecured notes issued in April 2015
FINANCING
Face amount	$ 2,000

FINANCING_ - Outstanding borrow

FINANCING: - Outstanding borrowing (Details) $ in Millions	Dec. 31, 2017USD ($)
Aggregate maturities of the outstanding borrowings
2,020	$ 400
2,022	300
Thereafter	5,351.2
Total	6,051.2
Total debt discount	$ 94.1

BENEFIT PLANS_ - Other (Details

BENEFIT PLANS: - Other (Details) $ in Millions	12 Months Ended
	Dec. 31, 2017USD ($)plan	Dec. 31, 2016USD ($)	Dec. 31, 2015USD ($)	Dec. 31, 2017USD ($)	Dec. 31, 2016USD ($)
Benefit plans
Number of noncontributory defined benefit pension plans | plan	2
Post retirement defined benefit plans
Defined benefit plan, net periodic benefit costs
Service cost	$ 0.8	$ 0.7	$ 1.1
Interest cost	1.4	1	1
Expected return on plan assets	(2.9)	(2.2)	(3)
Amortization of transition assets, net	0.1	0.1	0.1
Amortization of net actuarial loss			(0.5)
Settlement / Curtailment	0.1	(0.2)
Amortization of net loss (gain)	0.2	0.2	0.2
Net periodic benefit cost	(0.3)	(0.4)	(1.1)
Change in benefit obligation:
Projected benefit obligation at beginning of year	25.6	24.9
Service cost	0.8	0.7	1.1
Interest cost	1.4	1	1
Settlement	0.9	(0.1)
Benefits paid	(1.9)	(2)
Actuarial (gain)/loss	(0.3)	3.3
Actuarial gain assumption changes	0.3	(0.1)
Inflation adjustment	0.7	(2.1)
Projected benefit obligation at end of year	27.5	25.6	24.9
Change in plan assets:
Fair value of plan assets at beginning of year	44.6	46.8
Actual return on plan assets	6.9	4.5
Employer contributions	(0.4)	(0.4)
Benefits paid	(0.9)	(0.9)
Currency exchange rate adjustment	1.4	(5.4)
Fair value of plan assets at end of year	51.6	44.6	46.8
Funded status at end of year				$ 24.1	$ 19
Amounts recognized in statement of financial position
Non-current assets				24.2	19
Total				24.2	19
Amounts recognized in accumulated other comprehensive income
Net loss (gain)				2.3	4.8
Prior service cost (credit)				1.5	1
Total, net of tax	5.8	5.7	5.7	3.8	5.8
Net loss (gain), income taxes				(2)	(3.3)
Reconciliation of accumulated other comprehensive income:
Accumulated other comprehensive income at beginning of plan year	5.8	5.7
Net loss/(gain) amortized during the year	(0.1)	(0.2)
Net loss/(gain) occurring during the year	(2.4)	0.6
Prior service cost (credit)	0.4
Currency exchange rate adjustment	0.1	(0.3)
Net adjustment to accumulated other comprehensive income	(2)	0.1
Accumulated other comprehensive income at end of plan year	3.8	5.8	$ 5.7
Net adjustment to accumulated other comprehensive income, income taxes	1.3	(3.3)
Amounts in accumulated other comprehensive income amortized and recognized as a component of net periodic benefit cost, net of income tax
Net loss / (gain)	(2.4)	0.6
Amortization of net (loss) gain	(0.1)	(0.1)
Prior service cost (credit)	0.4
Total amortization expenses	$ (2.1)	$ 0.5
Expected Benefit Payments
2,018				2.3
2,019				1.7
2,020				1.8
2,021				1.9
2,022				2
2023 to 2025				12.4
Total				22.1
Post retirement defined benefit plans | Expatriate Plan
Assumptions used to determine the pension obligation and other post-retirement benefits and cost
Discount rate (as a percent)	3.25%	3.65%	3.80%
Expected long-term rate of return on plan asset (as a percent)	4.00%	4.00%	4.50%
Post retirement defined benefit plans | Mexican Health Plan
Assumptions used to determine the pension obligation and other post-retirement benefits and cost
Discount rate (as a percent)	7.80%	7.55%	6.80%
Expected long-term rate of return on plan asset (as a percent)	7.55%	7.55%	6.80%
Rate of increase in future compensation level (as a percent)	4.50%	4.50%	4.50%
Post-retirement Health care plans
Defined benefit plan, net periodic benefit costs
Interest cost	$ 0.9	$ 0.6	$ 1
Amortization of prior service cost (credit)	(0.2)	(0.5)	(0.4)
Net periodic benefit cost	0.7	0.1	0.6
Change in benefit obligation:
Projected benefit obligation at beginning of year	12.9	10.8
Interest cost	0.9	0.6	1
Actuarial loss/ (gain) - claims cost	(0.4)
Benefits paid	(0.9)	(0.8)
Actuarial (gain)/loss	(0.6)	3.9
Inflation adjustment	0.6	(1.6)
Projected benefit obligation at end of year	12.5	12.9	10.8
Change in plan assets:
Employer contributions	(0.1)	(0.1)
Benefits paid	(0.1)	(0.1)
Funded status at end of year				12.5	(12.9)
Amounts recognized in statement of financial position
Current liabilities				(0.1)	(0.1)
Non-current liabilities				(12.5)	(12.8)
Total				(12.6)	(12.9)
Amounts recognized in accumulated other comprehensive income
Net loss (gain)				(3.9)	(2.8)
Total, net of tax	(2.8)	(6.5)	(6.5)	(3.9)	(2.8)
Net loss (gain), income taxes				1.7	$ 1.4
Reconciliation of accumulated other comprehensive income:
Accumulated other comprehensive income at beginning of plan year	(2.8)	(6.5)
Net loss/(gain) amortized during the year	0.1	0.3
Net loss/(gain) occurring during the year	(0.6)	2.3
Currency exchange rate adjustment	(0.6)	1.1
Net adjustment to accumulated other comprehensive income	(1.1)	3.7
Accumulated other comprehensive income at end of plan year	(3.9)	(2.8)	$ (6.5)
Net adjustment to accumulated other comprehensive income, income taxes	0.3	1.9
Amounts in accumulated other comprehensive income amortized and recognized as a component of net periodic benefit cost, net of income tax
Net loss / (gain)	(0.6)	2.3
Amortization of net (loss) gain	0.1	0.3
Total amortization expenses	$ (0.5)	$ 2.6
Expected Benefit Payments
2,018				0.9
2,019				0.9
2,020				0.9
2,021				0.9
2,022				0.9
2023 to 2025				4.8
Total				$ 9.3
Post-retirement Health care plans | Expatriate Plan
Assumptions used to determine the pension obligation and other post-retirement benefits and cost
Discount rate (as a percent)	3.25%	3.65%	3.80%
Expected Benefit Payments
Assumed trend rate for covered health care benefit cost (as a percent)	5.90%
Assumed trend rate for covered health care benefit cost post-65 years of age (as a percent)	6.30%
Assumed ultimate trend rate for health care benefit cost (as a percent)	4.20%
Assumed ultimate trend rate for health care benefit cost post-65 years of age (as a percent)	4.60%
Post-retirement Health care plans | Mexican Health Plan
Expected Benefit Payments
Assumed trend rate for covered health care benefit cost (as a percent)	4.50%
Effect of one percentage-point change in assumed other benefit cost trend rates
Effect of one percentage-point increase on total service and interest cost components	$ 1
Effect of one percentage-point decrease on total service and interest cost components	0.8
Effect of one percentage-point increase on post-retirement benefit obligation	12.5
Effect of one percentage-point decrease on post-retirement benefit obligation	$ 11.3
Post-retirement Health care plans | Weighted average | Mexican Health Plan
Assumptions used to determine the pension obligation and other post-retirement benefits and cost
Discount rate (as a percent)	7.80%	7.55%	6.80%

BENEFIT PLANS_ - Post retiremen

BENEFIT PLANS: - Post retirement (Details) - Post retirement defined benefit plans $ / shares in Units, $ in Millions	12 Months Ended
	Dec. 31, 2017USD ($)entity$ / shares	Dec. 31, 2016
Expatriate Plan
Benefit plans
Net asset value (in dollars per share) | $ / shares	$ 1
Mexican Health Plan
Assumptions used to determine the pension obligation and other post-retirement benefits and cost
Number of financial institutions managing plan assets | entity	3
Plan obligations as a percentage of benefit obligation	30.00%
Asset allocation (as a percent)	100.00%	100.00%
Expected employer contribution in next fiscal year	$ 1.4
Pending payments to former Buenavista workers	$ 3.4
Parent Company (Grupo Mexico) common shares | Mexican Health Plan
Assumptions used to determine the pension obligation and other post-retirement benefits and cost
Asset allocation (as a percent)	70.00%
Equity securities | Mexican Health Plan
Assumptions used to determine the pension obligation and other post-retirement benefits and cost
Asset allocation (as a percent)	70.00%	78.00%
Treasury bills | Mexican Health Plan
Assumptions used to determine the pension obligation and other post-retirement benefits and cost
Asset allocation (as a percent)	30.00%	22.00%

COMMITMENTS AND CONTINGENCIES66

COMMITMENTS AND CONTINGENCIES: - Environmental Costs (Details) $ in Millions, MXN in Billions

Sep. 15, 2014MXN

Sep. 15, 2014USD ($)

Aug. 06, 2014m³

Dec. 31, 2017lawsuititemm³

Aug. 31, 2014item

Mar. 31, 2014

Sep. 30, 2016lawsuit

Jun. 30, 2015lawsuititem

Dec. 31, 2017USD ($)lawsuititem

Dec. 31, 2016USD ($)

Dec. 31, 2015USD ($)lawsuititem

Dec. 31, 2011categoryperson

Mar. 31, 2016lawsuit

Mar. 02, 2015USD ($)

Environmental costs

Environmental capital investment | $

$ 222.6

$ 250.4

$ 120.8

Number of collective action lawsuits

6

Number of subsidiaries against which lawsuits were filed

2

Number of collective action lawsuits dismissed

2

Remaining number of lawsuits | lawsuit

4

Number of civil actions seeking damages | lawsuit

33

33

Number of constitutional action lawsuits

4

Number of subsidiaries to which environmental impact authorizations were granted

1

Buenavista del Cobre, S.A. de C.V

Environmental costs

Volume of copper sulfate solution (in cubic meters) | m³

40,000

Excess provision credited to income on closure of trust | $

$ 10.2

Estimated total damages | $

$ 136.4

Number of civil actions seeking damages

8

3

Buenavista del Cobre, S.A. de C.V | Maximum

Environmental costs

Amount committed to the Mexican Federal Government to establish a trust

MXN 2

$ 150

Buenavista del Cobre, S.A. de C.V | Minimum

Environmental costs

Number of workers to clean the river

1,200

Peru

Environmental costs

Environmental capital investment | $

$ 93.7

110.3

$ 98.8

Number of atmospheric basins established that require further attention

3

AQS, new hours

24

AQS, new micrograms of SO2 | m³

250

AQS, old hours

24

Revised air quality standards for sulfur dioxide as per new environmental regulation (in micrograms per cubic meter) | m³

20

AQS, new micrograms of gaseous mercury | m³

2

Mean monthly AQS | m³

1.5

Number of months for identification of contaminated sites and around in facilities

12 months

Period for preparation of decontamination plan

P30M

Period of extension for preparation of decontamination plan

1 year

Number of days in which results of soil confirmation tests are to be presented to authorities

30 days

Mexico

Environmental costs

Environmental capital investment | $

$ 128.9

$ 140.1

$ 22

Number of categories of collective actions | category

3

Minimum number of people claiming injury due to collective action initiative in Civil Federal Procedures Code (CFPC) | person

30

Francisca Garcia Enriquez

Environmental costs

Remaining number of Collective action lawsuits | lawsuit

2

Number of additional constitutional lawsuits filed | lawsuit

2

Mario Alberto Salcido et al; Maria Elena Heredia Bustamante et al; Martin Eligio Ortiz Gamez et al and Maria de los Angeles Enriquez Bacame et al

Environmental costs

Number of constitutional action lawsuits | lawsuit

4

COMMITMENTS AND CONTINGENCIES67

COMMITMENTS AND CONTINGENCIES: - Litigation Matters (Details) $ in Millions	1 Months Ended	12 Months Ended
	Aug. 31, 2009USD ($)	Dec. 31, 2017halawsuititem	Dec. 31, 2012item	Dec. 31, 2005item	Mar. 31, 2012
Tia Maria
Litigation Matter
Area of mining concession (in hectares) | ha		32,989.64
Number of lawsuits | lawsuit		4
Virgen Maria
Litigation Matter
Area of mining concession (in hectares) | ha		943.72
Percentage of mining concession		2.90%
Purchase price of shares paid to former stockholders | $	$ 2
Mexico Generadora de Energia S. de R.L. ("MGE") | Controladora de Infraestructura Energetica Mexico, S. A. de C. V.
Litigation Matter
Acquisition percentage					99.999%
Peru | Labor Matters
Litigation Matter
Percentage of labor unionized		69.00%
Total number of workers		4,628
Number of labor unions		6
Number of labor unions represent majority of workers		1
Number of labor unions other than majority workers unions		5
Term of agreement		3 years
Annual salary increase (as a percent)		5.00%
Mexico | Mexico Generadora de Energia S. de R.L. ("MGE")
Litigation Matter
Number of power plants			2	2
Mexico | Mexico Generadora de Energia S. de R.L. ("MGE") | Controladora de Infraestructura Energetica Mexico, S. A. de C. V.
Litigation Matter
Acquisition percentage			99.999%

COMMITMENTS AND CONTINGENCIES68

COMMITMENTS AND CONTINGENCIES: - Other (Details) PEN in Millions, $ in Millions	1 Months Ended				12 Months Ended
	May 31, 2016	Jul. 31, 2014MW	Jun. 30, 2014MW	May 31, 2012MW	Dec. 31, 2017PENitemmkmT	Dec. 31, 2017USD ($)itemmkmT
Other commitments:
Commitment for capital projects						$ 1,409.3
Tia Maria | Peru
Other commitments:
Project budget						1,400
Amount spend as of the current date						$ 353.9
Annual production ( in tons) | T					120,000	120,000
Distance of sea water transportation | km					25	25
Height above sea level of the desalinization plant | m					1,000	1,000
Additional investment in desalinization plant						$ 95
Number of jobs expected to be generated | item					3,500	3,500
Number of workers expected to be directly employed | item					600	600
Number of workers expected to be indirectly employed | item					2,000	2,000
Term life of environmental project (in years)					20 years	20 years
Toquepala Concentrator Expansion | Peru
Other commitments:
Project budget						$ 1,200
Amount spend as of the current date						$ 892.9
Percentage of Work Completed (in percentage)					87.00%	87.00%
Amount committed to funding for social and infrastructure improvement projects					PEN 445	$ 132
Development Fund Moquegua Region | Peru
Other commitments:
Amount committed to funding for social and infrastructure improvement projects					PEN 700	$ 209
Copper | Toquepala Concentrator Expansion | Peru
Other commitments:
Estimated increase in annual production (in tons) | T					100,000	100,000
Molybdenum | Toquepala Concentrator Expansion | Peru
Other commitments:
Estimated increase in annual production (in tons) | T					3,100	3,100
Power purchase agreements | Electroperu S.A
Other commitments:
Term of power purchase agreement related to sale of power plant			20 years
Purchase agreement, contracted power capacity (in megawatts) | MW			120
Power purchase agreements | Kallpa | Peru
Other commitments:
Term of power purchase agreement related to sale of power plant	10 years	10 years
Purchase agreement, contracted power capacity (in megawatts) | MW		120
Power purchase agreements | Kallpa | Peru | Maximum
Other commitments:
Purchase agreement, contracted power capacity (in megawatts) | MW				80
Educational Project | Development Fund Moquegua Region | Peru
Other commitments:
Amount committed to funding for social and infrastructure improvement projects					PEN 108.5	$ 32
Water Treatment | Development Fund Moquegua Region | Peru
Other commitments:
Amount committed to funding for social and infrastructure improvement projects					48.4	14
Social Investment For Taxes | Development Fund Moquegua Region | Peru
Other commitments:
Amount committed to funding for social and infrastructure improvement projects					PEN 143	$ 43

STOCKHOLDERS' EQUITY - Treasury

STOCKHOLDERS' EQUITY - Treasury Stock (Details) - USD ($) $ in Millions	12 Months Ended					60 Months Ended	120 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2017
Activity in treasury stock
Balance at the beginning of the period	$ 2,987.6
Purchase of shares		$ 71.7	$ 1,004.4	$ 682.8	$ 281.4	$ 878.1	$ 2,918.4
Balance at the end of the period	$ 3,001.1	$ 2,987.6					$ 3,001.1
Southern copper common shares
Activity in treasury stock
Treasury stock balance at the end of the period (in shares)	111,567,617	111,579,617					111,567,617
Parent Company (Grupo Mexico) common shares
Activity in treasury stock
Treasury stock balance at the end of the period (in shares)	108,450,672	115,667,784					108,450,672
TREASURY STOCK: | Southern copper common shares
Activity in treasury stock
Balance at the beginning of the period	$ 2,769	$ 2,697.6
Purchase of shares		71.7	1,004.4
Used for corporate purposes	(0.3)	(0.3)	(0.3)
Balance at the end of the period	2,768.7	2,769	2,697.6				$ 2,768.7
TREASURY STOCK: | Parent Company (Grupo Mexico) common shares
Activity in treasury stock
Balance at the beginning of the period	218.6	211.3
Other activity, including dividend, interest and foreign currency transaction effect	13.8	7.3	4.2
Balance at the end of the period	$ 232.4	$ 218.6	$ 211.3				$ 232.4

STOCKHOLDERS' EQUITY - Repurcha

STOCKHOLDERS' EQUITY - Repurchase Program (Details) - USD ($) $ / shares in Units, $ in Millions	12 Months Ended				60 Months Ended	120 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2017	Dec. 31, 2008
SCC share repurchase program:
Amount authorized for share repurchase program						$ 3,000	$ 500
Total Number of Shares Purchased	2,937,801	36,689,052	22,711,428	10,245,000	46,914,486	119,497,767
Average Price Paid per Share (in dollars per share)	$ 24.42	$ 27.38	$ 30.06	$ 27.47	$ 18.72	$ 24.42
Total Number of Shares Purchased as Part of Publicly Announced Plan	119,497,767	116,559,966	79,870,914	57,159,486	46,914,486
Maximum Number of Shares that May Yet Be Purchased Under the Plan @ $47.45						1,720,408
Total Cost	$ 71.7	$ 1,004.4	$ 682.8	$ 281.4	$ 878.1	$ 2,918.4
Closing price of NYSE (in dollars per share)						$ 47.45
Percentage of Ownership by Parent	88.90%					88.90%

STOCKHOLDERS' EQUITY - Other (D

STOCKHOLDERS' EQUITY - Other (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016
Parent Company (Grupo Mexico) common shares
Activity in directors' stock award plan
Treasury stock balance at the end of the period (in shares)	108,450,672	115,667,784
Directors' Stock Award Plan
Share based Compensation Plan
Common shares received on election as director	1,200
Additional shares issued at each annual general meeting	1,200
Stock based compensation expense	$ 0.4	$ 0.3
Period of extension of plan	5 years
Total SCC shares reserved for the plan	600,000	600,000
Activity in directors' stock award plan
Total shares granted at the beginning of the period (in shares)	(334,800)	(322,800)
Granted in the period (in shares)	(12,000)	(12,000)
Total shares granted at the end of the period (in shares)	(346,800)	(334,800)
Remaining shares reserved	253,200	265,200

STOCKHOLDERS' EQUITY - Compensa

STOCKHOLDERS' EQUITY - Compensation Plan (Details) $ / shares in Units, $ in Millions	1 Months Ended		12 Months Ended
	Jan. 31, 2015MXN / shares	Jan. 31, 2015$ / shares	Dec. 31, 2017USD ($)$ / sharesshares	Dec. 31, 2016USD ($)$ / sharesshares	Dec. 31, 2015USD ($)$ / sharesshares	Dec. 31, 2010MXN / shares	Dec. 31, 2010$ / shares
Non-controlling interest
Investment shareholders' interest in Peruvian Branch (as a percent)			0.71%
Employee Stock Purchase 2010 Plan
Information related to compensation cost
Purchase price for initial subscription (in dollars per share) | (per share)						MXN 26.51	$ 1.28
Percentage of title acquired by employee in every two years on shares paid in previous two years			50.00%
Period of plan			8 years
Ratio of bonus shares granted to participant			0.1
Stock based compensation expense | $			$ 0.6	$ 0.6	$ 0.6
Unrecognized compensation expense | $			$ 0.2	$ 0.8	$ 1.4
Stock award activity, Shares
Outstanding shares at the beginning of the period | shares			1,401,096	2,227,582
Exercised (in shares) | shares			(7,433)	(826,486)
Outstanding shares at the end of the period | shares			1,393,663	1,401,096	2,227,582
Unit Weighted Average Grant Date Fair Value
Outstanding shares at the beginning of the period (in dollars per share) | $ / shares			$ 2.05	$ 2.05
Exercised (in dollars per share) | $ / shares			2.05	2.05
Outstanding shares at the end of the period (in dollars per share) | $ / shares			2.05	$ 2.05	$ 2.05
Employee Stock Purchase 2015 Plan
Information related to compensation cost
Purchase price for initial subscription (in dollars per share) | (per share)	MXN 38.44	$ 1.86	$ 1.86
Percentage of title acquired by employee in every two years on shares paid in previous two years			50.00%
Period of plan			8 years
Ratio of bonus shares granted to participant			0.1
Stock based compensation expense | $			$ 0.6	$ 0.6	$ 0.4
Unrecognized compensation expense | $			$ 3.2	$ 3.8	$ 4.4
Stock award activity, Shares
Outstanding shares at the beginning of the period | shares			2,540,223	2,656,386
Exercised (in shares) | shares			(247,103)	(116,163)
Outstanding shares at the end of the period | shares			2,293,120	2,540,223	2,656,386
Unit Weighted Average Grant Date Fair Value
Outstanding shares at the beginning of the period (in dollars per share) | $ / shares			$ 2.63	$ 2.63
Exercised (in dollars per share) | $ / shares			2.63	2.63
Outstanding shares at the end of the period (in dollars per share) | $ / shares			$ 2.63	$ 2.63	$ 2.63

FAIR VALUE MEASUREMENT (Details

FAIR VALUE MEASUREMENT (Details) - USD ($) $ in Millions	Dec. 31, 2017	Dec. 31, 2016
Liabilities:
Long-term debt, Carrying Value	$ 5,957.1	$ 5,954.2
Long-term debt, Fair Value	7,295	6,212
Short-term investment:
Trading securities	49.5	49.2
Available-for-sale debt securities:
Available-for-sale Securities, Current, Total	1	2.1
Quoted prices in active markets for identical assets (Level 1)
Liabilities:
Long-term debt, Carrying Value	5,208.4	5,903
Long-term debt, Fair Value	6,488.9	6,150.8
Significant other observable inputs (Level 2)
Liabilities:
Long-term debt, Carrying Value	748.7	51.2
Long-term debt, Fair Value	806.1	61.2
Fair value measurements recurring | Fair value as of the end of the period
Short-term investment:
Trading securities	49.5	49.2
Derivative:
Total assets, fair value	337.9	309.1
Fair value measurements recurring | Fair value as of the end of the period | Copper
Derivative:
Provisionally priced sales	184.6	203.8
Fair value measurements recurring | Fair value as of the end of the period | Molybdenum
Derivative:
Provisionally priced sales	102.8	54
Fair value measurements recurring | Corporate bonds | Fair value as of the end of the period
Available-for-sale debt securities:
Available-for-sale debt securities	0.1
Fair value measurements recurring | Asset backed securities | Fair value as of the end of the period
Available-for-sale debt securities:
Available-for-sale debt securities	0.5
Fair value measurements recurring | Mortgage backed securities | Fair value as of the end of the period
Available-for-sale debt securities:
Available-for-sale debt securities	0.4	2.1
Fair value measurements recurring | Quoted prices in active markets for identical assets (Level 1)
Short-term investment:
Trading securities	49.5	49.2
Derivative:
Total assets, fair value	336.9	307
Fair value measurements recurring | Quoted prices in active markets for identical assets (Level 1) | Copper
Derivative:
Provisionally priced sales	184.6	203.8
Fair value measurements recurring | Quoted prices in active markets for identical assets (Level 1) | Molybdenum
Derivative:
Provisionally priced sales	102.8	54
Fair value measurements recurring | Significant other observable inputs (Level 2)
Available-for-sale debt securities:
Available-for-sale Securities, Current, Total	1	2.1
Fair value measurements recurring | Significant other observable inputs (Level 2) | Corporate bonds
Available-for-sale debt securities:
Available-for-sale debt securities	0.1
Fair value measurements recurring | Significant other observable inputs (Level 2) | Asset backed securities
Available-for-sale debt securities:
Available-for-sale debt securities	0.5
Fair value measurements recurring | Significant other observable inputs (Level 2) | Mortgage backed securities
Available-for-sale debt securities:
Available-for-sale debt securities	$ 0.4	$ 2.1

CONCENTRATION OF RISK_ (Details

CONCENTRATION OF RISK: (Details) $ in Millions	12 Months Ended
	Dec. 31, 2017USD ($)item	Dec. 31, 2016	Dec. 31, 2015
Concentration of risk
Number of open-pit copper mines | item	4
Number of underground poly metallic mines | item	5
Number of smelters | item	2
Number of refineries | item	8
Cash equivalents
Concentration of risk
Total cash and short-term investment	$ 1,055.3
Percentage of total cash	100.00%
Percentage of cash in US dollars	94.90%
Cash equivalents | United States
Concentration of risk
Total cash and short-term investment	$ 655.1
Percentage of total cash	62.10%
Percentage invested in one institution of country	19.20%
Percentage invested in one institution of total cash	11.90%
Cash equivalents | Switzerland
Concentration of risk
Total cash and short-term investment	$ 319.5
Percentage of total cash	30.30%
Percentage invested in one institution of country	60.60%
Percentage invested in one institution of total cash	18.30%
Cash equivalents | Peru
Concentration of risk
Total cash and short-term investment	$ 23.5
Percentage of total cash	2.20%
Percentage invested in one institution of country	63.50%
Percentage invested in one institution of total cash	1.40%
Cash equivalents | Mexico
Concentration of risk
Total cash and short-term investment	$ 57.2
Percentage of total cash	5.40%
Percentage invested in one institution of country	61.40%
Percentage invested in one institution of total cash	3.30%
Accounts receivable trade | Five largest customers
Concentration of risk
Percentage of accounts receivable and total sales	28.40%	31.10%	32.40%
Accounts receivable trade | Largest customer
Concentration of risk
Percentage of accounts receivable and total sales	8.20%	11.90%	10.90%
Total sales | Five largest customers
Concentration of risk
Percentage of accounts receivable and total sales	25.10%	30.40%	28.00%
Total sales | Largest customer
Concentration of risk
Percentage of accounts receivable and total sales	8.80%	8.40%	7.70%

RELATED PARTY TRANSACTIONS_ (De

RELATED PARTY TRANSACTIONS: (Details) MXN in Millions, $ in Millions	Aug. 04, 2014item	May 31, 2010USD ($)	Mar. 31, 2012USD ($)	Dec. 31, 2017USD ($)	Dec. 31, 2016USD ($)	Dec. 31, 2015USD ($)	Dec. 31, 2012itemMW	Dec. 31, 2005item	Mar. 31, 2012MXN	Mar. 31, 2012USD ($)
RELATED PARTY TRANSACTIONS:
Related parties receivable current:				$ 26.1	$ 23.4
Related parties payable:				$ 90.1	62.2
Ownership percentage				0.71%
Grupo Mexico and affiliates
RELATED PARTY TRANSACTIONS:
Total purchases				$ 474.6	398.9	$ 280.6
Total sales				197.6	134.7	155.9
Mexico Generadora de Energia S. de R.L. ("MGE")
RELATED PARTY TRANSACTIONS:
Related parties receivable current:				16.2	10.2
Related parties payable:				38.5	13.9
Total purchases				223.7	233.8	143.3
Total sales				101	95.9	81.7
Maximum amount of line of credit granted to related party		$ 350
Interest rate (as a percent)		4.40%
Loan repaid			$ 150
Interest earned					4.2	9.2
Mexico Generadora de Energia S. de R.L. ("MGE") | Maximum
RELATED PARTY TRANSACTIONS:
Ownership percentage									0.001%	0.001%
Mexico Generadora de Energia S. de R.L. ("MGE") | Mexico
RELATED PARTY TRANSACTIONS:
Number of power plants | item							2	2
Net total capacity (in megawatts) | MW							516.2
Percentage of supply to third-party energy users							13.50%
Mexico Generadora de Energia S. de R.L. ("MGE") | Controladora de Infraestructura Energetica Mexico, S. A. de C. V.
RELATED PARTY TRANSACTIONS:
Percentage of interest acquired									99.999%	99.999%
Value of interest acquired									MXN 1,928.6	$ 150
Mexico Generadora de Energia S. de R.L. ("MGE") | Controladora de Infraestructura Energetica Mexico, S. A. de C. V. | Mexico
RELATED PARTY TRANSACTIONS:
Percentage of interest acquired							99.999%
Asarco LLC
RELATED PARTY TRANSACTIONS:
Related parties receivable current:				4.1	5.5
Related parties payable:				24.2	36.3
Total purchases				37.2	30.3	32
Total sales				96.2	37.1	72.3
Grupo Mexico
RELATED PARTY TRANSACTIONS:
Related parties receivable current:				2.8	4.5
Related parties payable:				0.7	0.1
Total purchases				14	13.8	13.8
Total sales				0.2	0.6	0.5
Donations				1.9
Compania Perforadora Mexico S.A.P.I. de C.V. and affiliates
RELATED PARTY TRANSACTIONS:
Related parties receivable current:				1.4	1.3
Total purchases					0.3	0.3
Total sales				0.2	0.6	0.6
Mexico Proyectos y Desarrollos, S.A. de C.V. and affiliates
RELATED PARTY TRANSACTIONS:
Related parties receivable current:				1.1	1.5
Related parties payable:				21.7	7.8
Total purchases				152.9	76	57.3
Total sales					0.4	0.8
Operadora de Generadoras de Energia Mexico S.A. de C.V.
RELATED PARTY TRANSACTIONS:
Related parties receivable current:					0.1
Total sales					0.1
Ferrocarril Mexicano, S.A. de C.V.
RELATED PARTY TRANSACTIONS:
Related parties payable:				2.6	3
Total purchases				43.5	42.7	27.3
Eolica El Retiro, S.A.P.I. de C.V.
RELATED PARTY TRANSACTIONS:
Related parties payable:				0.8	0.1
Total purchases				3.3	2	6.6
Number of wind turbines | item	37
Percentage of supply to third-party energy users	27.00%
Related to the controlling group
RELATED PARTY TRANSACTIONS:
Total purchases				1.7	2.9	2.9
Total sales				0.7	0.5	0.8
Operadora de Cinemas S.A. de C.V.
RELATED PARTY TRANSACTIONS:
Related parties receivable current:				0.3	0.2
Related parties payable:				0.7	0.4
Total purchases				0.1	0.5	0.5
Total sales				0.2	0.1	0.2
Boutique Bowling de Mexico S.A. de C.V.
RELATED PARTY TRANSACTIONS:
Related parties receivable current:				0.2	0.1
Related parties payable:				0.6	0.2
Total purchases				0.3	0.4	0.4
Total sales				0.2	0.2	0.3
Mexico Transportes Aereos S.A. de C.V. ("Mextransport")
RELATED PARTY TRANSACTIONS:
Related parties payable:				0.3	0.1
Total purchases				1.3	2	2
Total sales				0.3	0.2	0.3
Related to SCC executive officers
RELATED PARTY TRANSACTIONS:
Total purchases				0.2	2	8.8
Breaker, S.A. de C.V and affiliates ("Breaker")
RELATED PARTY TRANSACTIONS:
Related parties payable:					0.3
Total purchases					0.5	5.5
Higher Technology S.A.C.
RELATED PARTY TRANSACTIONS:
Total purchases					1	1.4
Servicios y Fabricaciones Mecanicas S.A.C.
RELATED PARTY TRANSACTIONS:
Total purchases				$ 0.2	$ 0.5	0.7
Sempertrans and affiliates
RELATED PARTY TRANSACTIONS:
Total purchases						$ 1.2
Equity investment in affiliate
RELATED PARTY TRANSACTIONS:
Ownership percentage				44.20%

SEGMENT AND RELATED INFORMATI76

SEGMENT AND RELATED INFORMATION: - Financial (Details) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2017USD ($)	Sep. 30, 2017USD ($)	Jun. 30, 2017USD ($)	Mar. 31, 2017USD ($)	Dec. 31, 2016USD ($)	Sep. 30, 2016USD ($)	Jun. 30, 2016USD ($)	Mar. 31, 2016USD ($)	Dec. 31, 2017USD ($)segmentcountryitem	Dec. 31, 2016USD ($)	Dec. 31, 2015USD ($)
Financial information related to segments
Number of reportable segments | segment									3
Number of countries having open-pit operations | country									2
Financial information relating to segments
Net sales outside of segments									$ 6,654,500	$ 5,379,800	$ 5,045,900
Cost of sales (exclusive of depreciation, amortization and depletion)									3,252,800	3,034,100	2,927,600
Selling, general and administrative									93,100	94,300	99,400
Depreciation, amortization and depletion									671,100	647,100	510,700
Exploration									28,800	40,100	48,800
Environmental remediation									(10,200)		45,000
Operating income	$ 830,000	$ 692,600	$ 525,900	$ 570,400	$ 470,500	$ 362,400	$ 385,100	$ 346,200	2,618,900	1,564,200	1,414,400
Interest, net									(300,500)	(283,600)	(199,900)
Other income (expense)									(15,700)	(24,600)	(25,300)
Income taxes									(1,593,400)	(501,100)	(464,900)
Equity earnings of affiliate									23,100	23,900	16,800
Non-controlling interest									(3,900)	(2,300)	(4,700)
Net income attributable to SCC	(287,400)	$ 401,800	$ 299,700	$ 314,400	171,900	$ 197,600	$ 221,900	$ 185,100	728,500	776,500	736,400
Capital investment									1,023,500	1,118,500	1,250,000
Property and mine development, net	9,099,600				8,766,500				9,099,600	8,766,500	8,262,800
Total assets	13,780,100				13,234,300				13,780,100	13,234,300	12,593,200
Payment to acquire business, net of cash acquired											100,400
Intersegment sales
Financial information relating to segments
Net sales outside of segments									(71,000)
Corporate, other and eliminations
Financial information relating to segments
Net sales outside of segments										(72,000)	(67,600)
Cost of sales (exclusive of depreciation, amortization and depletion)									(69,600)	(73,400)	(75,200)
Selling, general and administrative									1,100	2,300	1,100
Depreciation, amortization and depletion									10,300	15,500	(17,200)
Exploration									6,200	16,900	19,500
Operating income									(19,000)	(33,300)	4,200
Capital investment									4,000	4,700	105,100
Property and mine development, net	338,400				231,700				338,400	231,700	404,200
Total assets	253,400				9,600				$ 253,400	9,600	383,300
Mexican Open-pit
Financial information related to segments
Number of open-pit copper mines | item									2
Mexican Open-pit | Operating segment
Financial information relating to segments
Net sales outside of segments									$ 3,972,700	3,234,300	2,703,900
Cost of sales (exclusive of depreciation, amortization and depletion)									1,594,300	1,523,200	1,390,000
Selling, general and administrative									47,900	47,100	50,500
Depreciation, amortization and depletion									401,000	364,700	265,000
Exploration									2,700	5,200	7,800
Environmental remediation									(10,200)		45,000
Operating income									1,937,000	1,294,100	945,600
Capital investment									297,600	537,000	820,500
Property and mine development, net	5,004,500				5,136,800				5,004,500	5,136,800	4,879,300
Total assets	8,323,100				8,174,400				$ 8,323,100	8,174,400	7,459,800
Mexican IMMSA Unit
Financial information related to segments
Number of underground poly metal mines | item									5
Mexican IMMSA Unit | Operating segment
Financial information relating to segments
Net sales outside of segments									$ 437,700	351,100	320,700
Cost of sales (exclusive of depreciation, amortization and depletion)									365,300	304,100	323,800
Selling, general and administrative									7,900	7,400	6,400
Depreciation, amortization and depletion									56,200	49,800	34,800
Exploration									5,500	5,000	9,600
Operating income									73,800	56,800	13,700
Capital investment									36,500	35,800	39,200
Property and mine development, net	366,900				448,700				366,900	448,700	395,800
Total assets	889,100				825,000				889,100	825,000	787,500
Mexican IMMSA Unit | Intersegment sales
Financial information relating to segments
Net sales outside of segments									$ 71,000	72,000	67,600
Peruvian Operations
Financial information related to segments
Number of open-pit copper mines | item									2
Peruvian Operations | Operating segment
Financial information relating to segments
Net sales outside of segments									$ 2,244,100	1,794,400	2,021,300
Cost of sales (exclusive of depreciation, amortization and depletion)									1,362,800	1,280,200	1,289,000
Selling, general and administrative									36,200	37,500	41,400
Depreciation, amortization and depletion									203,600	217,100	228,100
Exploration									14,400	13,000	11,900
Operating income									627,100	246,600	450,900
Capital investment									685,400	541,000	285,200
Property and mine development, net	3,389,800				2,949,300				3,389,800	2,949,300	2,583,500
Total assets	$ 4,314,500				$ 4,225,300				$ 4,314,500	$ 4,225,300	3,962,600
El Pilar | Corporate, other and eliminations
Financial information relating to segments
Payment to acquire business, net of cash acquired											$ 100,400

SEGMENT AND RELATED INFORMATI77

SEGMENT AND RELATED INFORMATION: - Sales (Details) - USD ($) $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
SALES VALUE PER SEGMENT:
Net sales outside of segments	$ 1,864.3	$ 1,676.5	$ 1,529.8	$ 1,583.9	$ 1,398.9	$ 1,400.7	$ 1,335.1	$ 1,245.1	$ 6,654.5	$ 5,379.8	$ 5,045.9
Copper
SALES VALUE PER SEGMENT:
Net sales outside of segments									5,476.5	4,220.8	3,994.1
Molybdenum
SALES VALUE PER SEGMENT:
Net sales outside of segments									353.4	268	239
Silver
SALES VALUE PER SEGMENT:
Net sales outside of segments									286.3	294.3	226.7
Zinc
SALES VALUE PER SEGMENT:
Net sales outside of segments									326.6	234.4	210.7
Other
SALES VALUE PER SEGMENT:
Net sales outside of segments									211.7	362.3	375.4
Corporate, other and eliminations
SALES VALUE PER SEGMENT:
Net sales outside of segments									(71.8)	(72)	(67.6)
Corporate, other and eliminations | Copper
SALES VALUE PER SEGMENT:
Net sales outside of segments									(37.3)	(32)	(30.6)
Corporate, other and eliminations | Silver
SALES VALUE PER SEGMENT:
Net sales outside of segments									(26.9)	(31.6)	(26.5)
Corporate, other and eliminations | Zinc
SALES VALUE PER SEGMENT:
Net sales outside of segments									(0.6)
Corporate, other and eliminations | Other
SALES VALUE PER SEGMENT:
Net sales outside of segments									(7)	(8.4)	(10.5)
Mexican Open-pit | Operating segment
SALES VALUE PER SEGMENT:
Net sales outside of segments									3,972.7	3,234.3	2,703.9
Mexican Open-pit | Operating segment | Copper
SALES VALUE PER SEGMENT:
Net sales outside of segments									3,480.2	2,663.1	2,237.2
Mexican Open-pit | Operating segment | Molybdenum
SALES VALUE PER SEGMENT:
Net sales outside of segments									224	144	109
Mexican Open-pit | Operating segment | Silver
SALES VALUE PER SEGMENT:
Net sales outside of segments									170.7	182.3	129.5
Mexican Open-pit | Operating segment | Other
SALES VALUE PER SEGMENT:
Net sales outside of segments									97.8	244.9	228.2
Mexican IMMSA Unit | Operating segment
SALES VALUE PER SEGMENT:
Net sales outside of segments									509.5	423.1	388.3
Mexican IMMSA Unit | Operating segment | Copper
SALES VALUE PER SEGMENT:
Net sales outside of segments									37.2	32	30.6
Mexican IMMSA Unit | Operating segment | Silver
SALES VALUE PER SEGMENT:
Net sales outside of segments									71.9	82.1	66.5
Mexican IMMSA Unit | Operating segment | Zinc
SALES VALUE PER SEGMENT:
Net sales outside of segments									327.2	234.4	210.7
Mexican IMMSA Unit | Operating segment | Other
SALES VALUE PER SEGMENT:
Net sales outside of segments									73.2	74.6	80.5
Peruvian Operations | Operating segment
SALES VALUE PER SEGMENT:
Net sales outside of segments									2,244.1	1,794.4	2,021.3
Peruvian Operations | Operating segment | Copper
SALES VALUE PER SEGMENT:
Net sales outside of segments									1,996.4	1,557.7	1,756.9
Peruvian Operations | Operating segment | Molybdenum
SALES VALUE PER SEGMENT:
Net sales outside of segments									129.4	124	130
Peruvian Operations | Operating segment | Silver
SALES VALUE PER SEGMENT:
Net sales outside of segments									70.6	61.5	57.2
Peruvian Operations | Operating segment | Other
SALES VALUE PER SEGMENT:
Net sales outside of segments									$ 47.7	$ 51.2	$ 77.2

SEGMENT AND RELATED INFORMATI78

SEGMENT AND RELATED INFORMATION: - Geographical (Details) - USD ($) $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Schedule of revenue by geographical location
Net sales	$ 1,864.3	$ 1,676.5	$ 1,529.8	$ 1,583.9	$ 1,398.9	$ 1,400.7	$ 1,335.1	$ 1,245.1	$ 6,654.5	$ 5,379.8	$ 5,045.9
Mexico
Schedule of revenue by geographical location
Net sales									1,551.5	1,409.7	1,641
United States
Schedule of revenue by geographical location
Net sales									1,162.5	1,050	864
Peru
Schedule of revenue by geographical location
Net sales									374.3	294.4	324.3
Brazil
Schedule of revenue by geographical location
Net sales									240.1	196	276.4
Chile
Schedule of revenue by geographical location
Net sales									103.4	92.4	102
Other American countries
Schedule of revenue by geographical location
Net sales									91.5	74.3	89.2
Switzerland
Schedule of revenue by geographical location
Net sales									602.4	398.1	294.9
Italy
Schedule of revenue by geographical location
Net sales									332.4	343.8	324.1
Other European Countries
Schedule of revenue by geographical location
Net sales									480	273.1	125.4
Singapore
Schedule of revenue by geographical location
Net sales									1,051.3	652.7	312.8
Japan
Schedule of revenue by geographical location
Net sales									479.5	409.8	335
Other Asian countries
Schedule of revenue by geographical location
Net sales									$ 185.6	$ 185.5	$ 356.8

SEGMENT AND RELATED INFORMATI79

SEGMENT AND RELATED INFORMATION: - Provisional Sale (Details) lb in Millions, $ in Millions	12 Months Ended
	Dec. 31, 2017USD ($)lb$ / lb	Dec. 31, 2016USD ($)
Provisionally priced sales
Provisional price sales adjustment amounts included in net sales	$ (22.9)	$ (5.8)
Copper
Provisionally priced sales
Provisional price sales adjustment amounts included in accounts receivable	$ (8.3)	(6.2)
Copper | January through March 2018
Provisionally priced sales
Sales volume (in million lbs.) | lb	56.3
Provisional price | $ / lb	3.28
Molybdenum
Provisionally priced sales
Provisional price sales adjustment amounts included in accounts receivable	$ (14.6)	$ 0.4
Molybdenum | January through March 2018
Provisionally priced sales
Sales volume (in million lbs.) | lb	10
Provisional price | $ / lb	10.25

SEGMENT AND RELATED INFORMATI80

SEGMENT AND RELATED INFORMATION: - Long Term Sales Contract (Details)	12 Months Ended
	Dec. 31, 2017T
Copper cathodes | Mitsui
Long-term sales contract
Term of agreement	5 years
Quantity to be supplied related to additional annual contract in 2015 (in tons)	6,000
Quantity to be supplied related to additional annual contract from 2016 until 2019 (in tons)	48,000
Additional term in which contract may be renewed	5 years
Copper cathodes | Mitsui | Tia Maria
Long-term sales contract
Quantity to be supplied following the full startup of project (in tons)	24,000
Molybdenum concentrates | Molibdenos y Metales
Long-term sales contract
Quantity to be supplied (in tons)	26,220
Period for which contract can be extended	1 year
Minimum period for which contract is to be maintained	3 years
Molybdenum concentrates | Molymex
Long-term sales contract
Minimum percentage of total production required to be supplied	80.00%

QUARTERLY DATA (unaudited) (Det

QUARTERLY DATA (unaudited) (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
QUARTERLY DATA (unaudited)
Net sales	$ 1,864.3	$ 1,676.5	$ 1,529.8	$ 1,583.9	$ 1,398.9	$ 1,400.7	$ 1,335.1	$ 1,245.1	$ 6,654.5	$ 5,379.8	$ 5,045.9
Gross profit	864.4	725.7	553.8	586.7	502	394.7	419	382.9	2,730.6	1,698.6
Operating income	830	692.6	525.9	570.4	470.5	362.4	385.1	346.2	2,618.9	1,564.2	1,414.4
Net income (loss)	(286.2)	402.8	300.5	315.3	172.3	198.2	222.6	185.7	732.4	778.8	741.1
Net income (loss) attributable to SCC	$ (287.4)	$ 401.8	$ 299.7	$ 314.4	$ 171.9	$ 197.6	$ 221.9	$ 185.1	$ 728.5	$ 776.5	$ 736.4
Per share amounts attributable to SCC:
Net earnings basic and diluted (in dollars per share)	$ (0.38)	$ 0.52	$ 0.39	$ 0.41	$ 0.22	$ 0.26	$ 0.29	$ 0.23	$ 0.94	$ 1	$ 0.93
Dividend per share	$ 0.25	$ 0.14	$ 0.12	$ 0.08	$ 0.05	$ 0.05	$ 0.05	$ 0.03	$ 0.59	$ 0.18	$ 0.34

SUBSEQUENT EVENTS (Details)

SUBSEQUENT EVENTS (Details) - Subsequent Events $ / shares in Units, $ in Millions	Feb. 20, 2018USD ($)T	Jan. 25, 2018$ / shares
SUBSEQUENT EVENTS
Quarterly dividend authorized (in dollars per share) | $ / shares		$ 0.30
Michiquillay project in Cajamarca, Peru
SUBSEQUENT EVENTS
Tender proposed price | $	$ 400
Annual royalty on net sales (as a percent)	3.00%
Mineralized material (in tons) | T	1,150,000,000
Percentage of copper content in mineralized material	0.63%
Estimated capital investment | $	$ 2,500
Expected production of copper per year (in tons) | T	225,000
Minimum initial estimated mine life (in years)	25 years

Schedule II - Valuation and Q83

Schedule II - Valuation and Qualifying Accounts and Reserves (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Accounts Receivable
Valuation and Qualifying Accounts and Reserves
Balance at beginning of period	$ 0.7	$ 0.9	$ 0.3
Charged to costs and expenses	0.6		0.6
Deductions/Applications	0.2	0.2
Balance at end of period	1.1	0.7	0.9
Notes issued under par
Valuation and Qualifying Accounts and Reserves
Balance at beginning of period	62.2	63.8	45.1
Charged to costs and expenses	1.7	1.6	1.5
Additions			20.2
Balance at end of period	60.5	$ 62.2	$ 63.8
Valuation allowance
Valuation and Qualifying Accounts and Reserves
Charged to costs and expenses	619.6
Balance at end of period	$ 619.6