Hudbay Minerals (HBM) 40-F30 Mar 212020 FY Annual report (Canada)Financial data

Company Profile

Document and Entity Information

Document and Entity Information	12 Months Ended
Document and Entity Information	Dec. 31, 2020shares
Document and Entity Information [Abstract]
Entity Registrant Name	Hudbay Minerals Inc.
Entity Central Index Key	0001322422
Entity Current Reporting Status	Yes
Document Type	40-F
Document Period End Date	Dec. 31, 2020
Current Fiscal Year End Date	--12-31
Entity Interactive Data Current	Yes
Document Fiscal Year Focus	2020
Document Fiscal Period Focus	FY
Entity Common Stock, Shares Outstanding	261,272,151
Amendment Flag	false
Entity Emerging Growth Company	false

Consolidated Balance Sheets

Consolidated Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Current
Cash	$ 439,135	$ 396,146
Trade and other receivables	141,199	105,994
Inventories	143,105	138,820
Prepaid expenses and other current assets	16,717	12,737
Other financial assets	3,073	2,049
Taxes receivable	12,446	7,289
Total Current assets	755,675	663,035
Receivables	18,568	19,264
Inventories	22,006	19,455
Other financial assets	15,669	11,287
Intangibles and other assets	21,173	10,411
Property, plant and equipment	3,731,655	3,662,559
Deferred tax assets	101,899	75,046
Total Assets	4,666,645	4,461,057
Current liabilities
Trade and other payables	233,147	192,404
Taxes payable	2,701	2,146
Other liabilities	51,971	49,411
Other financial liabilities	24,713	28,076
Lease liabilities	33,473	32,781
Deferred revenue	102,782	86,933
Total Current liabilities	448,787	391,751
Other financial liabilities	194,378	39,784
Lease liabilities	30,041	49,166
Long-term debt	1,135,675	985,255
Deferred revenue	443,902	476,823
Provisions	331,799	280,850
Pension obligations	23,316	29,599
Other employee benefits	129,508	116,778
Deferred tax liabilities	229,433	242,928
Total liabilities	2,966,839	2,612,934
Equity
Share capital	1,777,340	1,777,340
Reserves	(24,200)	(24,250)
Retained earnings	(53,334)	95,033
Total equity	1,699,806	1,848,123
Total liabilities and equity	$ 4,666,645	$ 4,461,057

Consolidated Income Statements

Consolidated Income Statements - USD ($) $ in Thousands	12 Months Ended
Consolidated Income Statements - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Income Statement
Revenue	$ 1,092,418	$ 1,237,439
Cost of sales
Mine operating costs	691,591	741,342
Depreciation and amortization	361,827	344,555
Cost of Sales	1,053,418	1,085,897
Gross profit	39,000	151,542
Selling and administrative expenses	41,408	36,170
Exploration and evaluation expenses	17,196	30,774
Other operating expenses	17,583	51,116
Impairment loss	0	322,249
Results from operating activities	(37,187)	(288,767)
Net interest expense on long term debt	82,712	68,375
Accretion on streaming arrangements	56,670	69,772
Change in fair value of financial instruments	(29,370)	8,247
Other net finance costs	31,890	17,602
Net finance expense	141,902	163,996
Loss before tax	(179,089)	(452,763)
Tax recovery	(34,505)	(108,953)
Loss for the year	$ (144,584)	$ (343,810)
Loss per share
Basic and diluted (in dollars per share)	$ (0.55)	$ (1.32)
Weighted average number of common shares outstanding:
Basic and diluted (in shares)	261,272,151	261,272,151

Consolidated Statements of Cash

Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Cash generated from operating activities:
Loss for the year	$ (144,584)	$ (343,810)
Tax recovery	(34,505)	(108,953)
Items not affecting cash:
Depreciation and amortization	363,603	346,634
Share-based compensation	15,008	2,714
Net interest expense on long term debt	82,712	68,375
Accretion on streaming arrangements	56,670	69,772
Change in fair value of financial instruments	(29,370)	8,247
Other net finance costs	31,890	17,602
Inventory write-down	32	504
Amortization of deferred revenue and variable consideration	(73,931)	(76,103)
Pension and other employee benefit payments, net of accruals	3,043	2,148
Write-down of UCM Receivable		25,978
Asset impairment		322,249
Decommissioning and restoration payments	(18,737)	(4,136)
Other	2,673	2,916
Taxes paid	(12,641)	(26,853)
Operating cash flow before change in non-cash working capital	241,863	307,284
Change in non-cash working capital	(2,383)	3,572
Net cash flows from operating activities	239,480	310,856
Cash used in investing activities:
Acquisition of property, plant and equipment	(361,185)	(259,202)
Acquisition of subsidiary, net of cash acquired		(44,688)
Change in restricted cash		3,401
Interest received	2,167	8,119
Net cash flows from investing activities	(359,018)	(292,370)
Cash generated from/(used) in financing activities:
Issuance of senior unsecured notes, net of transaction costs	591,824
Principal repayments	(400,000)
Premium paid on redemption of notes	(7,252)
Interest paid on long-term debt	(81,517)	(74,750)
Financing costs	(16,204)	(26,149)
Lease payments	(35,980)	(32,952)
Gold prepayment proceeds	115,005
Dividends paid	(3,783)	(3,927)
Net cash flows from financing activities	162,093	(137,778)
Effect of movement in exchange rates on cash and cash equivalents	434	(59)
Net increase (decrease) in cash	42,989	(119,351)
Cash, beginning of the year	396,146	515,497
Cash, end of the year	$ 439,135	$ 396,146

Consolidated Statements of Comp

Consolidated Statements of Comprehensive Loss - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Statement of Income and Comprehensive Income
Loss for the year	$ (144,584)	$ (343,810)
Item that will be reclassified subsequently to profit or loss:
Net gain (loss) on translation of foreign currency balances	4,170	9,220
Total other comprehensive income that will be reclassified to profit or loss, net of tax	4,170	9,220
Items that will not be reclassified subsequently to profit or loss:
Gold prepayment revaluation	(1,885)	0
Tax effect	506	0
Remeasurement - actuarial loss	(2,598)	(20,072)
Tax effect	(1,265)	1,878
Total other comprehensive income that will not be reclassified to profit or loss, net of tax	(5,242)	(18,194)
Transferred to income statement:
Other comprehensive loss net of tax, for the year	(1,072)	(8,974)
Total comprehensive loss for the year	$ (145,656)	$ (352,784)

Consolidated Statements of Chan

Consolidated Statements of Changes in Equity - USD ($) $ in Thousands	Share capital [Member]	Other capital reserves [Member]	Foreign currency translation reserve [Member]	Remeasurement reserve [Member]	Retained earnings [Member]	Total
Beginning Balance at Dec. 31, 2018	$ 1,777,340	$ 28,837	$ (11,819)	$ (58,272)	$ 442,770	$ 2,178,856
Statements [Line Items]
Profit (Loss)					(343,810)	(343,810)
Other comprehensive income (loss)			9,220	(18,194)		(8,974)
Total comprehensive income (loss)			9,220	(18,194)	(343,810)	(352,784)
Dilution of Partner's interest in Rosemont		25,978				25,978
Contributions by and distributions to owners:
Dividends					(3,927)	(3,927)
Total contributions by and distributions to owners					(3,927)	(3,927)
Ending Balance at Dec. 31, 2019	1,777,340	54,815	(2,599)	(76,466)	95,033	1,848,123
Statements [Line Items]
Profit (Loss)					(144,584)	(144,584)
Other comprehensive income (loss)			4,170	(5,242)		(1,072)
Total comprehensive income (loss)			4,170	(5,242)	(144,584)	(145,656)
Contributions by and distributions to owners:
Dividends					(3,783)	(3,783)
Stock options		1,122				1,122
Total contributions by and distributions to owners		(1,122)			3,783	2,661
Ending Balance at Dec. 31, 2020	$ 1,777,340	$ 55,937	$ 1,571	$ (81,708)	$ (53,334)	$ 1,699,806

Reporting entity

Reporting entity	12 Months Ended
Reporting entity	Dec. 31, 2020
Disclosure Of Corporate Information [Abstract]
Reporting entity [Text Block]	1. Reporting entity On January 1, 2017, Hudbay Minerals Inc. amalgamated under the Canada Business Corporations Act Wholly owned subsidiaries as at December 31, 2020 and 2019 include HudBay Marketing & Sales Inc. ("HMS"), HudBay Peru Inc., HudBay Peru S.A.C. ("Hudbay Peru"), HudBay (BVI) Inc., Hudbay Arizona Inc, Rosemont Copper Company ("Rosemont") and Mason Resources (US) Inc. ("Mason"). Hudbay is an integrated mining company primarily producing copper concentrate (containing copper, gold and silver), molybdenum concentrate and zinc metal. With assets in North and South America, Hudbay is focused on the discovery, production and marketing of base and precious metals. Directly and through its subsidiaries, Hudbay owns three polymetallic mines, four ore concentrators and a zinc production facility in northern Manitoba and Saskatchewan (Canada) and Cusco (Peru) and copper projects in Arizona and Nevada (United States). Hudbay also has equity investments in a number of junior exploration companies. The Company is governed by the Canada Business Corporations Act and its shares are listed under the symbol "HBM" on the Toronto Stock Exchange, New York Stock Exchange and Bolsa de Valores de Lima.

Basis of preparation

Basis of preparation	12 Months Ended
Basis of preparation	Dec. 31, 2020
Basis Of Preparation [Abstract]
Basis of preparation [Text Block]	2. Basis of preparation (a) Statement of compliance: These consolidated financial statements have been prepared in accordance with International Financial Reporting Standards ("IFRS") as issued by the International Accounting Standards Board ("IASB") effective for the year ended December 31, 2020. The Board of Directors approved these consolidated financial statements on February 18, 2021. (b) Functional and presentation currency: Hudbay's consolidated financial statements are presented in US dollars, which is the Company's and all material subsidiaries' functional currency, except the Company's Manitoba business unit, which has a functional currency of Canadian dollars. All values are rounded to the nearest thousand ($000) except where otherwise indicated. (c) Basis of measurement: The consolidated financial statements have been prepared on the historical cost basis except for the following items in the consolidated balance sheets: - Derivatives, embedded derivatives, other financial instruments, and financial assets measured at fair value through profit or loss ("FVTPL"); - Liabilities for cash-settled share-based compensation arrangements are measured at fair value; and, - A defined benefit liability is recognized as the net total of the plan assets, unrecognized past service costs and unrecognized actuarial losses, less unrecognized actuarial gains and the present value of the defined benefit obligation. (d) COVID-19 estimation uncertainty: At the end of 2019, a novel strain of coronavirus ("COVID-19") was reported in China. The COVID-19 outbreak has developed rapidly in 2020, with a significant number of infections around the world, including regions Hudbay operates in. On March 11, 2020, the World Health Organization declared the COVID-19 outbreak a global pandemic. Since then, containment measures have resulted in decreased economic activity, which has adversely affected the broader global economy. The resulting impacts on global commerce have been and continue to be far-reaching. To date there has been volatility in stock markets, commodities and foreign exchange markets, restrictions on the conduct of business in many jurisdictions and the global movement of people and some goods have become restricted. The Company has evaluated the potential impacts arising from COVID-19 on all aspects of its business, with particular attention to indicators of impairment / reversal of impairment of non-financial assets, inventory and accounts receivable valuations, impacts on pension and other employee benefit discount rates, and deferred tax provisions. In all these areas, for the year ended December 31, 2020, there was no significant financial impact on the Company. (e) Use of judgements and estimates: The preparation of the consolidated financial statements in conformity with IFRS requires Hudbay to make judgements, estimates and assumptions that affect the application of accounting policies, reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the consolidated financial statements, and reported amounts of revenue and expenses during the reporting period. Actual results may differ from these estimates. Hudbay reviews these estimates and underlying assumptions on an ongoing basis, based on experience and other factors, including expectations of future events that the Company believes to be reasonable under the circumstances. Revisions to accounting estimates are recognized prospectively in the period in which the estimates are revised and in any future periods affected. The following are critical and significant judgements and estimates impacting the consolidated financial statements: - I n - I FRS 15 - Revenue- stream transactions (note 18) - - M i Changes in the mineral reserve or resource estimates may affect: - - - - - - Property plant and equipment (notes 3i and 12) - - Acquisition method accounting (notes 3a and 5) - Tax provisions (notes 3o and 22 - Assaying utilized to determine revenue and recoverability of inventories (notes 3c and 3f) - - Decommissioning and restoration obligations (notes 3m and 19) - - Pension and other employee benefit (notes 3l, 20 and 21) - s

Significant accounting policies

Significant accounting policies	12 Months Ended
Significant accounting policies	Dec. 31, 2020
Significant Accounting Policies [Abstract]
Significant accounting policies [Text Block]	3. Significant accounting policies The accounting policies set out below have been applied consistently to all periods presented in these consolidated financial statements and by all Hudbay's entities. a) Basis of consolidation: Intercompany balances and transactions are eliminated upon consolidation. When a Hudbay entity transacts with an associate or jointly controlled entity of the Company, unrealized profits and losses are eliminated to the extent of Hudbay's interest in the relevant associate or joint venture. The accounting policies of Hudbay's entities are changed when necessary to align them with the policies adopted by the Company. Subsidiaries A subsidiary is an entity controlled by Hudbay. The financial statements of subsidiaries are included in the consolidated financial statements from the date that control commences until the date that control ceases. Business combinations and goodwill When Hudbay makes an acquisition, it first determines whether the assets acquired and liabilities assumed constitute a business, in which case the acquisition requires accounting as a business combination. Management applies judgement in determining whether the acquiree is capable of being conducted and managed for the purpose of providing a return, considering the inputs of the acquiree and processes applied to those inputs that have the ability to create outputs. Hudbay applies the acquisition method of accounting to business combinations, whereby the goodwill is measured at the acquisition date as the fair value of the consideration transferred including the recognized amount of any non-controlling interests in the acquiree. When the excess is negative, a bargain purchase gain is recognized immediately in the consolidated income statements. The assessment of fair values on acquisition includes those mineral reserves and resources that are able to be reliably measured. In determining these fair values, management must also apply judgement in areas including future cash flows, metal prices, exchange rates and appropriate discount rates. Changes in such estimates and assumptions could result in significant differences in the amount of goodwill recognized. The consideration transferred is the aggregate of the fair values, at the date of the acquisition, of the sum of the assets transferred, the liabilities incurred or assumed, and the equity instruments issued by the acquirer in exchange for control of the acquiree. Acquisition-related costs are recognized in the consolidated income statements as incurred, unless they relate to issuance of debt or equity securities. Where applicable, the consideration transferred includes any asset or liability resulting from a contingent consideration arrangement and measured at its acquisition date fair value. Subsequent changes in such fair values are adjusted against the cost of acquisition where they qualify as measurement period adjustments. All other subsequent changes in the fair value of contingent consideration classified as an asset or liability are accounted for in accordance with relevant IFRS. Changes in the fair value of contingent consideration classified as equity are not recognized. Where a business combination is achieved in stages, the Company's previously held interests in the acquired entity are remeasured to fair value at the acquisition date, which is the date Hudbay attains control, and any resulting gain or loss is recognized in the consolidated income statements. Amounts previously recognized in other comprehensive income ("OCI") related to interests in the acquiree prior to the acquisition date are reclassified to the consolidated income statements, where such treatment would be appropriate if that interest were disposed of. After initial recognition, goodwill is measured at cost less any accumulated impairment losses. For the purpose of impairment testing, goodwill acquired in a business combination is, from the acquisition date, allocated to each of Hudbay's CGUs that are expected to benefit from the synergies of the combination, irrespective of whether other assets or liabilities of the acquiree are assigned to those units. Goodwill is allocated to the lowest level at which it is monitored for internal management purposes and is not larger than an operating segment before aggregation. Where goodwill forms part of a CGU and part of the operation within that unit is disposed of, the goodwill associated with the disposed operation is included in the determination of any gain or loss on disposal. Goodwill is not amortized and is tested for impairment annually and whenever there is an indication of impairment. If any such indication exists, the recoverable amount of the CGU is estimated in order to determine the extent of the impairment, if any. The recoverable amount is determined as the higher of fair value less direct costs to sell and the CGU's value in use. An impairment loss in respect of goodwill is not reversed. Fair value for mineral interests and related goodwill is generally determined as the present value of the estimated future cash flows expected to arise from the continued use of the asset, including any expansion prospects, and its eventual disposal, using assumptions that an independent market participant may take into account. Value in use is determined as the present value of the estimated future cash flows expected to arise from the continued use of the asset in its present form and its eventual disposal. Value in use is determined by applying assumptions specific to Hudbay's continued use and cannot take into account future development. The weighted average cost of capital of Hudbay or comparable market participants is used as a starting point for determining the discount rates, with appropriate adjustments for the risk profile of the countries in which the individual CGUs operate and the specific risks related to the development of the project. Where the asset does not generate cash flows that are independent of other assets, Hudbay estimates the recoverable amount of the CGU to which the asset belongs. If the carrying amount of an asset or CGU exceeds its recoverable amount, the carrying amount of the asset or CGU is reduced to its recoverable amount. An impairment loss is recognized as an expense in the consolidated income statements. b) Translation of foreign currencies: Management determines the functional currency of each Hudbay entity as the currency of the primary economic environment in which the entity operates. Foreign currency transactions Transactions in foreign currencies are translated to the respective functional currencies of Hudbay's entities at exchange rates in effect at the transaction dates. At the end of each reporting period, monetary assets and liabilities denominated in foreign currencies are translated to the functional currency using the closing exchange rate. Non-monetary assets and liabilities measured at fair value are translated using the exchange rates at the date when fair value was determined. Non-monetary assets and liabilities measured at historical cost in a foreign currency are translated using exchange rates that were in effect at the transaction dates. The same translations are applied when an entity prepares its financial statements from books and records maintained in a currency other than its functional currency, except revenue and expenses may be translated at monthly average exchange rates that approximate those in effect at the transaction dates. Foreign currency gains and losses arising on period-end revaluations are recognized in the consolidated income statements, except for a financial liability designated as a hedge of a net investment in a foreign operation, or qualifying cash flow hedges, which are recognized in OCI. Foreign operations For the purpose of the consolidated financial statements, assets and liabilities of Hudbay's entities that have functional currencies other than the US dollar are translated to US dollars at the reporting date using the closing exchange rate. Revenue and expenses are translated at monthly average exchange rates that approximate those in effect at the transaction dates. Differences arising from these foreign currency translations are recognized in OCI and presented within equity in the foreign currency translation reserve. When a foreign operation is disposed, the relevant exchange differences accumulated in the foreign currency translation reserve are transferred to the consolidated income statements as part of the profit or loss on disposal. On the partial disposal of a subsidiary that includes a foreign operation, the relevant proportion of such amount is reattributed to non-controlling interests. On disposal of a partial investment in an associate or joint venture that includes a foreign operation while retaining significant influence or joint control, the relevant proportion is reclassified to profit or loss. Net investment in a foreign operation Foreign currency gains and losses arising on translation of a monetary item receivable from or payable to a foreign operation for which settlement is neither planned nor likely to occur in the foreseeable future are considered to form part of a net investment in the foreign operation. Such gains and losses are recognized in OCI and presented within equity in the foreign currency translation reserve. c) Revenue from the sale of goods is measured at the fair value of the consideration received or receivable, net of treatment and refining charges and pre-production revenue. Revenue from the sale of by-products is included within revenue. Revenue is recognized when control of the goods sold has been transferred to the buyer. Control is deemed to have passed to the customer when significant risk and reward of the product has passed to the buyer, Hudbay has a present right to payment and physical possession of the product has been transferred to the buyer. Sale of concentrate and finished zinc frequently occur under the following terms, and management has assessed these terms in order to determine timing of transfer of control. Incoterms used by Hudbay Revenue recognized when goods: Cost, Insurance and Freight (CIF) Are loaded on board the vessel Free on Board (FOB) Are loaded on board the vessel Delivered at place (DAP) Arrive at the named place of destination Delivered at terminal (DAT) Arrive at the named place of destination Free Carrier (FCA) Arrive at the named place of delivery Sales of concentrate and certain other products are provisionally priced. For these contracts, sales prices are subject to final adjustment at the end of a future period after shipment, based on quoted market prices during the quotational period specified in the contract. Revenue is recognized when the above criteria are achieved, using weight and assay results and forward market prices to estimate the fair value of the total consideration receivable. Therefore, revenue is initially recorded based on an initial provisional invoice. Subsequently, at each reporting date, until the provisionally priced sale is finalized, sales receivables are marked to market, with adjustments (both gains and losses) recorded within revenue separately as "Pricing and volume adjustments" in the notes to the consolidated financial statements and in trade and other receivables on the consolidated balance sheets. As per IFRS 15 Revenue, variability in price is deemed to be fair value movements on provisionally priced receivables under the scope of IFRS 9 Financial Instruments; variability in quantities is deemed to be variable consideration. The variable consideration from weights and assay changes to quantities has been assessed to be insignificant to warrant precluding revenue being recorded as a result of possible future sales reversals. An annual analysis of the accuracy of our weights and assays is completed, and if the accuracy rate falls below a certain threshold, management then evaluates whether revenue from future sales should be constrained as a result of it being highly probable that there would be a significant revenue reversal in the future. Hudbay only includes in the transaction price an amount which is not highly likely to be subject to significant subsequent revenue reversal. Within sales contracts with customers, separate performance obligations may arise pertaining to the shipping of goods sold. If applicable, costs and the transaction price are allocated on a relative standalone selling basis to any separate performance obligations and are recognized over the period of time the goods sold are shipped, on a gross basis. Hudbay recognizes deferred revenue in the event it receives payments from customers before a sale meets criteria for revenue recognition. There is a significant financing component associated with the Company's precious metal streaming arrangements since funds were received in advance of the delivery of concentrate. When a significant financing component is recognized, finance expense will be higher and revenues will be higher as the larger deferred revenue balance is amortized to revenues. A market-based discount rate is utilized at the inception of each of the respective stream agreements to determine a discount rate for computing the interest charges for the significant financing component of the deferred revenue balance. As product is delivered, the deferred revenue amount including accreted interest will be drawn down. The draw down rate requires the use of proven and probable reserves and certain resources in the calculation that are beyond proven and probable reserves which management is reasonably confident will be transferable to reserves. Key estimates used in determining the significant financing component include the discount rate and the reserve and resources assumed for conversion. d) Cost of sales: Cost of sales consists of those costs previously included in the measurement of inventory sold during the period, as well as certain costs not included in the measurement of inventory, such as the cost of warehousing and distribution to customers, provisional pricing adjustments related to purchased concentrates, profit sharing, royalty payments, share-based compensation expense and other indirect expenses related to producing operations. e) Cash and cash equivalents include cash, demand deposits and short-term, highly liquid investments that are readily convertible to known amounts of cash and are subject to an insignificant risk of changes in value. Cash equivalents have maturities of three months or less at the date of acquisition. Interest earned is included in finance income on the consolidated income statements and in investing activities on the consolidated statements of cash flows. Amounts that are restricted from being used for at least twelve months after the reporting date are classified as non-current assets and presented in restricted cash on the consolidated balance sheets. Changes in restricted cash balances are classified as investing activities on the consolidated statements of cash flows. f) Inventories consist of stockpiles, in-process inventory (concentrates and metals), metal products and supplies. Concentrates, metals and all other saleable products are valued at the lower of cost and estimated net realizable value. Net realizable value represents the estimated selling price for inventories less all estimated costs of completion and costs necessary to make the sale. Where the net realizable value is less than cost, the difference is charged to the consolidated income statements as an impairment charge in cost of sales. Costs associated with stripping activities in an open pit mine are capitalized to inventory and recorded through cost of sales unless the stripping activity can be shown to improve access to further quantities of ore that will be mined in future periods, in which case, the stripping costs are capitalized to property, plant and equipment. Cost of production of concentrate inventory is determined on a weighted average cost basis and the cost of production of finished metal inventory is determined using the first in first out basis. The cost of production includes direct costs associated with conversion of production inventory based on normal production capacity: material, labour, contractor expenses, purchased concentrates, and an attributable portion of production overheads and depreciation of all property, plant and equipment involved with the mining and production process. Hudbay measures in-process inventories based on assays of material received at metallurgical plants and estimates of recoveries in the production processes. Due to significant uncertainty associated with volume and metal content, immaterial costs are not allocated to routine operating levels of stockpiled ore. Estimates and judgements are required to assess the nature of any significant changes to levels of ore stockpiles and determining whether allocation of costs is required. Supplies are valued at the lower of average cost and net realizable value. g) Computer software is measured at cost less accumulated amortization and accumulated impairment losses. Costs include all directly attributable costs necessary to create, produce and prepare the asset to be capable of operating it in the manner intended by management. Amortization methods, useful lives, and residual values if any, are reviewed at each year end and adjusted prospectively, if required. When an intangible asset is disposed of, or when no further economic benefits are expected, the asset is derecognized, and any resulting gain or loss is recorded in the consolidated income statements. Currently, the Company's intangible assets relate primarily to enterprise resource planning ("ERP") information systems, which are amortized over their estimated useful lives. h) Exploration and evaluation expenditures: Exploration and evaluation activity begins when Hudbay obtains legal rights to explore a specific area and involves the search for mineral reserves, the determination of technical feasibility, and the assessment of commercial viability of an identified resource. Expenditures incurred in the exploration and evaluation phase include the cost of acquiring interests in mineral rights, licenses and properties and the costs of Hudbay's exploration activities, such as researching and analyzing existing exploration data, gathering data through geological studies, exploratory drilling, trenching, sampling, and certain feasibility studies. Hudbay expenses the cost of its exploration and evaluation activities and capitalizes the cost of acquiring interests in mineral rights, licenses and properties in business combinations, asset acquisitions or option agreements. Amounts capitalized are recognized as exploration and evaluation assets and presented in property, plant and equipment. Exploration and evaluation assets acquired as a result of an asset acquisition or option agreement are initially recognized at cost, and those acquired in a business combination are recognized at fair value on the acquisition date. They are subsequently carried at cost less accumulated impairment. No depreciation is charged during the exploration and evaluation phase. Hudbay expenses the cost of subsequent exploration and evaluation activity related to acquired exploration and evaluation assets. Cash flows associated with acquiring exploration and evaluation assets are classified as investing activities in the consolidated statements of cash flows; those associated with exploration and evaluation expenses are classified as operating activities. Judgement is required in determining whether the respective costs are eligible for capitalization where applicable, and whether they are likely to be recoverable, which may be based on assumptions about future events and circumstances. Estimates and assumptions made may change if new information becomes available. Hudbay monitors exploration and evaluation assets for factors that may indicate their carrying amounts are not recoverable. If such indicators are identified, the Company tests the exploration and evaluation assets or their CGUs, as applicable, for impairment. Hudbay also tests for impairment when assets reach the end of the exploration and evaluation phase. Exploration and evaluation assets are transferred to capital works in progress within property, plant and equipment once the Company determines that probable future economic benefits will be generated as a result of the expenditures. Hudbay's determination of probable future economic benefit is based on management's evaluation of the technical feasibility and commercial viability of the geological properties of a given ore body based on information obtained through evaluation activities, including metallurgical testing, resource and reserve estimates and the economic assessment of whether the ore body can be mined economically. Tools that may be used to determine this include a preliminary feasibility study, confidence in converting resources into reserves and the probability that the property could be developed into a mine site. At that time, the property is considered to enter the development phase, and subsequent evaluation costs are capitalized. (i) Hudbay measures items of property, plant and equipment at cost less accumulated depreciation and any accumulated impairment losses. The initial cost of an item of property, plant and equipment includes its purchase price or construction costs, including import duties and non-refundable purchase taxes, any costs directly attributable to bringing the asset into operation, and for qualifying assets, borrowing costs. The initial cost of property, plant and equipment also includes the initial estimate of the cost of dismantling and removing the item and restoring the site on which it is located, the obligation which Hudbay incurs either when the item is acquired or as a consequence of having used the item during a particular period for purposes other than to produce inventories during that period. Capitalization of costs ceases once an asset is in the location and condition necessary for it to be capable of operating in the manner intended by management. At this time, depreciation commences. For a new mine, this occurs upon commencement of commercial production. Up to and including December 31, 2020, any revenue earned in the process of preparing an asset to be capable of operating in the manner intended by management is included in the cost of the constructed asset. Any other incidental revenue earned prior to commencement of commercial production is recognized in the consolidated income statements. Carrying amounts of property, plant and equipment, including right-of-use ("ROU") assets, are depreciated to their estimated residual value over the estimated useful lives of the assets or the estimated life of the related mine or plant, if shorter. Where components of an asset have different useful lives, depreciation is calculated on each separate component. Components may be physical or non-physical, including the cost of regular major inspections and overhauls required in order to continue operating an item of property, plant and equipment. Certain items of property, plant and equipment are depreciated on a unit-of-production basis. The unit-of-production method is based on proven and probable tonnes of ore reserves. There are numerous uncertainties inherent in estimating ore reserves, and assumptions that were valid at the reporting date may change when new information becomes available. The actual volume of ore extracted and any changes in these assumptions could affect prospective depreciation rates and carrying values. The carrying amount of an item of property, plant and equipment is derecognized on disposal or when no future economic benefits are expected from its use or disposal. Upon derecognition of an item of property, plant and equipment, the difference between its carrying value and net sales proceeds, if any, is presented as a gain or loss in other operating income or expense in the consolidated income statements. i. Capital works in progress: Capital works in progress consist of items of property, plant and equipment in the course of construction or mineral properties in the course of development, including those transferred upon completion of the exploration and evaluation phase. On completion of construction or development, costs are transferred to plant and equipment and/or mining properties as appropriate. Capital works in progress are not depreciated. ii. Mining properties: Mining properties consist of costs transferred from capital works in progress when a mining property reaches commercial production, costs of subsequent mine and exploration development, and acquired mining properties in the production stage. Mining properties include costs directly attributable to bringing a mineral asset into the state where it is capable of operating in the manner intended by management and includes such costs as the cost of shafts, ramps, track haulage drifts, ancillary drifts, pumps, electrical substations, refuge stations, ventilation raises, permanent manways, and ore and waste pass raises. The determination of development costs to be capitalized during the production stage of a mine operation requires the use of judgements and estimates such as estimates of tonnes of waste to be removed over the life of the mining area and economically recoverable reserves extracted as a result. A mining property is considered to be capable of operating in a manner intended by management when it commences commercial production based on pre-established criteria. Upon commencement of commercial production, a mining property is depreciated on a unit-of-production method. Unit-of-production depreciation rates are determined based on the related proven and probable mineral reserves and associated future development costs. Subsequent mine development costs are capitalized to the extent they are incurred in order to access reserves mineable over more than one year. Ongoing maintenance and development expenditures are expensed as incurred and included in cost of sales in profit or loss. These include ore stope access drifts, footwall and hangingwall drifts in stopes, drawpoints, drill drifts, sublevels, slots, drill raises, stope manway access raises and definition diamond drilling. iii. Plant and equipment: Plant and equipment consists of buildings and fixtures, surface and underground fixed and mobile equipment and assets under lease. Plant and equipment are depreciated on either unit-of-production or straight-line basis based on factors including the production life of assets and mineable reserves. In general, mining assets are depreciated using a unit-of-production method; equipment is depreciated using the straight-line method, based on the shorter of its useful life and that of the related mine or facility; and plants are depreciated using the straight-line method, with useful lives limited by those of related mining assets. iv. Right-of-use lease assets: At inception of a contract, Hudbay assesses whether a contract is, or contains, a lease. A contract is, or contains, a lease if the contract conveys the right to control the use of an identified asset for a period of time in exchange for consideration. The Company assesses the following criteria in the determination of whether a contract conveys the right to control the use of an identified asset: • The contract involves the use of an identified asset - this may be specified explicitly or implicitly, and should be physically distinct or represent substantially all of the capacity of a physically distinct asset. If the supplier has substantive substitution rights, then the asset is not identified; • Hudbay has the right to obtain substantially all of the economic benefits from use of the asset throughout the period of use; and • Hudbay has the right to direct the use of the asset by means of decision making rights that are most relevant to changing how and for what purpose the asset is used. In the case where decisions about the asset's purpose is predetermined, Hudbay is deemed to have the right to direct the use of the asset if either: • Hudbay has the right to operate the asset; or, • Hudbay designed the asset in a way that predetermines how and for what purpose it will be used. The Company recognizes a ROU asset and lease liability at the lease commencement date. The initial measurement of the ROU asset is on a present value basis. This is based on the calculated lease liability plus any initial direct costs incurred, an estimate of removal or restoration costs, and any payments made prior to commencement of the lease less any lease incentives received. The right of use asset is subsequently depreciated using the straight-line method from the commencement date to the earlier of the end of the useful life of the right-of-use asset or the end of the lease term. The estimated useful lives of the right-of-use assets are determined on the same basis as those of property and equipment. In addition, the right-of-use asset is periodically reduced by impairment losses, if any, and adjusted for certain remeasurements of the lease liability. The lease liability is measured at the present value of the lease payments that are yet to be paid at the commencement date, discounted using the interest rate implicit in the lease or, if that rate cannot be easily determined, Hudbay's incremental borrowing rate. Generally, the Company uses its incremental borrowing rate as the discount rate for applicable leases. Lease payments included in the measurement of the lease liability comprise fixed payments including in substance fixed payments and variable payments that depend on an index or rate, amounts expected to be payable under a residual value guarantee and the additional costs Hudbay reasonably expects to incur due to purchase options, extension options and termination options reasonably expected to be exercised. The lease liability is measured at amortized cost using the effective interest method. It is remeasured when there is a change in the expected future cash flows of a leasing contract either due to a change in index or rate, or due to a change in terms of the contract. When the lease liability is remeasured in this way, a corresponding adjustment is made to the carrying amount of the right-of-use asset, or is recorded in profit or loss if the carrying amount of the right-of-use asset is zero. Hudbay has elected not to separate non-lease components and account for the lease and non-lease components as a single lease component for lease contracts of all asset classes. The Company has elected not to recognize ROU assets and lease liabilities for short-term leases of machinery that have a lease term of 12 months or less and leases of low-value assets. Hudbay recognizes the lease payments associated with these leases as an expense on a straight-line basis over the lease term. Hudbay does not enter into transactions where the Company acts as a lessor. The incremental borrowing rate used for new ROU leases is a key management judgement. v. Depreciation rates of major categories of assets: • Capital works in progress - not depreciated • Mining properties - unit-of- production • Mining asset - unit-of- production • Plant and Equipment ◦ Equipment - straight-line over 1 to 20 years ◦ Other plant assets - straight-line over 1 to 20 years/unit-of-production • ROU Assets - straight -line over 1 to 20 years Hudbay reviews its depreciation methods, remaining useful lives and residual values at least annually and accounts for changes in estimates prospectively. vi. Commercial production: Commercial production is the level of activities intended by management for a mine, or a mine and mill complex, to be capable of operating in the manner intended by management. Hudbay considers a range of factors when determining the level of activity that represents commercial production for a particular project, including a predetermined percentage of design capacity for the mine and mill; achievement of continuous production, ramp-ups, or other output; or specific factors such as recoveries, grades, or inventory build-ups. In a phased mining approach, management may consider achievement of specific milestones at each phase of completion. In a non-phased mining approach, management considers average actual metrics that are at least 60% of average design capacity or plan over a continuous period. Management assesses the operation's ability to sustain production over a period of approximately one to three months, depending on the complexity related

New standards

New standards	12 Months Ended
New standards	Dec. 31, 2020
Disclosure of changes in accounting estimates [abstract]
New standards [Text Block]	4. New standards New standards and interpretations adopted (a) Amendment to IFRS 3 - Business Combinations The amendment to IFRS 3 clarifies the definition of a business and includes an optional concentration test to determine whether an acquired set of activities and assets is a business. This amendment is in effect January 1, 2020 and will be applied prospectively to future acquisition transactions. New standards and interpretations not yet adopted (b) Amendment to IAS 16 - Property, Plant and Equipment The amendments to IAS 16 prohibit deducting from the cost of property, plant and equipment the proceeds from selling items produced while bringing the assets to the location and condition necessary for them to be capable of operating in the manner intended by management. Instead, a company will recognize such sales proceeds and related cost in profit or loss. This amendment is in effect January 1, 2022 with early adoption permitted. Hudbay intends to early adopt this amendment as of January 1, 2021 with retrospective application only to items of property, plant and equipment that were brought to the location and condition necessary for them to be capable of operating in the manner intended by management on or after January 1, 2020. The Company expects that the adoption of this amendment will impact the 2021 consolidated financial statements as it expects certain development projects to achieve commercial production in 2021, however, no restatement of prior periods is expected. (c) Interest Rate Benchmark Reform - Phase II - Amendments to IFRS 9, IAS 39, IFRS 7, IFRS 4 and IFRS 6 These amendments require companies to determine if there is a significant change in the basis of determining contractual cash flows as a result of interest rate benchmark reform / IBOR reform. A company will be required to determine if the replacement of an existing interest rate benchmark with an alternative rate benchmark results in contractual cash flows that are significantly different for financial instruments, lease payments, insurance contracts and/or items that use hedge accounting. If IBOR reform result in a transition on an economically equivalent basis with no value transfer having occurred, the changes to the standard allow the contractual cash flow changes to be applied prospectively, similar to a change in a market rate. These amendments are in effect for periods beginning on or after January 1, 2021 with earlier application being permitted and with retrospective application required. An entity is not required to restate prior periods. Hudbay does not believe the impact of these amendments will result in material changes to the consolidated financial statements.

Acquisition of remaining intere

Acquisition of remaining interest in the Rosemont project	12 Months Ended
Acquisition of remaining interest in the Rosemont project	Dec. 31, 2020
Disclosure of detailed information about business combination [abstract]
Acquisition of remaining interest in the Rosemont project [Text Block]	5. Acquisition of remaining interest in the Rosemont project In March 2019, the Company entered into an agreement with United Copper & Moly LLC ("UCM") to purchase UCM's remaining 7.95% interest in the Rosemont project, and to terminate all of UCM's remaining earn-in and off-take rights. The acquisition was completed on April 25, 2019. Upfront cash consideration of $45,000 was paid on April 25, 2019, and the Company also committed to pay three annual installments of $10,000 per year, commencing July 1, 2022. To facilitate an orderly acquisition of UCM's interest in Rosemont, Hudbay, immediately prior to closing the acquisition, agreed to release UCM from repayment obligations under an intercompany Rosemont project loan in exchange for an increase in equity interest in Rosemont. As a result, the loan receivable balance of $25,978 was written off. The Company recognized the loss on the loan receivable in the income statement (refer to note 6d). In addition, in order to recognize previously unfunded contributions to the Rosemont Project due from UCM, Hudbay recognized an increase to other capital reserves, a component of shareholder's equity. The acquisition provides Hudbay with 100% ownership of Rosemont, allowing greater strategic flexibility with respect to capital structure and project financing alternatives. In exchange for acquiring the percentage ownership not already owned by Hudbay, the Company paid: Cash $ 45,000 Present value of future cash installments 23,557 Total consideration $ 68,557 As part of the increase in ownership of the Rosemont Project, Hudbay acquired and assumed the following assets and liabilities, which represented the fair value of the assets and liabilities not already owned by Hudbay at the time of transaction: Current assets $ 343 Non-current assets 68,904 Liabilities (690 ) Net assets acquired $ 68,557

Revenue and expenses

Revenue and expenses	12 Months Ended
Revenue and expenses	Dec. 31, 2020
Analysis of income and expense [abstract]
Revenue and expenses [Text Block]	6. Revenue and expenses (a) Revenue Hudbay's revenue by significant product types: Year ended 2020 2019 Copper $ 563,910 $ 786,332 Zinc 264,106 284,897 Gold 180,949 120,366 Silver 25,986 29,315 Molybdenum 25,627 31,270 Other 5,619 4,760 1,066,197 1,256,940 Non-cash streaming arrangement items 1 Amortization of deferred revenue - gold 27,854 32,028 Amortization of deferred revenue - silver 39,409 60,370 Amortization of deferred revenue - variable 6,668 (16,295 ) 73,931 76,103 Pricing and volume adjustments 2 9,178 (12,123 ) 1,149,306 1,320,920 Treatment and refining charges (56,888 ) (83,481 ) $ 1,092,418 $ 1,237,439 1 2 Consideration from the Company's stream agreements is considered variable (note 18). Gold and silver stream revenue can be subject to cumulative adjustments when the amount of precious metals to be delivered under the contract changes. As a result of changes in the Company's mineral reserve and resource estimate in the first quarter of 2020 and amendments made to the 777 mine plan in the third quarter of 2020, the amortization rate by which deferred revenue is drawn down into income was adjusted and, as required, a current period catch up adjustment is made for all prior year stream revenues since the stream agreement inception date. This variable consideration adjustment for the year ended December 31, 2020 resulted in increased revenue of $6,668. The variable consideration adjustment for the year ended December 31, 2019 resulted in a reversal of revenue of $16,295. (b) Depreciation and amortization Depreciation of property, plant and equipment and amortization of intangible assets are reflected in the consolidated income statements as follows: Year ended December 31, 2020 2019 Cost of sales $ 361,827 $ 344,555 Selling and administrative expenses 1,776 2,079 $ 363,603 $ 346,634 (c) Share-based compensation expenses Share-based compensation expenses are reflected in the consolidated income statements as follows: Cash-settled Total share-based compensation expense RSUs DSUs PSUs Stock options Year ended December 31, 2020 Cost of sales $ 1,400 $ — $ — $ — $ 1,400 Selling and administrative 4,872 5,149 1,987 1,122 13,130 Other expenses 478 — — — 478 $ 6,750 $ 5,149 $ 1,987 $ 1,122 $ 15,008 Year ended December 31, 2019 Cost of sales $ 400 $ — $ — $ — $ 400 Selling and administrative 928 1,157 — — 2,085 Other expenses 229 — — — 229 $ 1,557 $ 1,157 $ — $ — $ 2,714 During the twelve months ended December 31, 2020, the Compan (twelve months ended December 31, 2019 - nil). For further details on stock options, see note 24b. (d) Other expenses Year ended December 31, 2020 2019 Regional costs $ 3,602 $ 3,780 Loss on disposal of property, plant and equipment 5,088 4,807 Closure cost adjustment - non-producing properties 2,721 2,289 Allocation of community costs 2,880 2,216 Write down of UCM receivable — 25,978 Pampacancha delivery obligation — 7,499 Other 3,292 4,547 $ 17,583 $ 51,116 During the first quarter of 2019, Hudbay recognized an obligation to deliver additional precious metal credits to Wheaton Precious Metals ("Wheaton") as a result of Hudbay's expectation that mining at the Pampacancha deposit would not begin until after January 1, 2020. The obligation was paid in four quarterly installments, with all payments having been made in 2020. (e) Impairment During 2019, Hudbay recorded impairment losses of $322,249 for non-current assets relating to the Arizona cash generating units ("CGU"). Arizona Pre-tax impairment to: Property, plant & equipment $ 322,249 Tax impact - (recovery) (80,143 ) After-tax impairment charge $ 242,106 On July 31, 2019, the U.S. District Court of the District of Arizona ("Court") issued a ruling in the lawsuits challenging the U.S. Forest Service's issuance of the Final Record of Decision ("FROD") for the Rosemont project in Arizona. The Court ruled to vacate and remand the FROD thereby delaying the expected start of construction of Rosemont. Hudbay and the U.S. federal government have appealed the Court's decision to the U.S. Ninth Circuit Court of Appeals. However, the Court's ruling and the subsequent impact to the Company's market capitalization gave rise to an indicator of impairment. Following an impairment test conducted as of September 30, 2019, it was determined that the recoverable amount of the Arizona CGU was lower than its carrying value, causing Hudbay to recognize an impairment loss related to these assets. (f) Employee benefits expense This table presents employee benefit expense recognized in Hudbay's consolidated income statements, including amounts transferred from inventory upon sale of goods: Year ended December 31, 2020 2019 Current employee benefits $ 179,486 $ 171,173 Share-based compensation (notes 6c, 19, 24) Equity settled stock options 1,122 — Cash-settled restricted share units 6,750 1,557 Cash-settled deferred share units 5,149 1,157 Cash-settled performance share units 1,987 — Employee share purchase plan 1,783 1,645 Post-employee pension benefits Defined benefit plans 11,671 10,643 Defined contribution plans 1,774 1,635 Other post-retirement employee benefits 9,305 8,457 Termination benefits 582 628 $ 219,609 $ 196,895 Manitoba has a profit sharing plan required by the collective bargaining agreement whereby 10% of Manitoba's after tax profit (excluding provisions or recoveries for deferred income tax and deferred mining tax) for any given fiscal year will be distributed to all eligible employees in the Flin Flon/Snow Lake operations, with the exception of executive officers and key management personnel. Peru has a profit sharing plan required by Peruvian law whereby 8% of Peru's taxable income will be distributed to all employees within Peru's operations The Company has an employee share purchase plan for executives and other eligible employees where participants may contribute between 1% and 10% of their pre-tax base salary to acquire Hudbay shares. The Company makes a matching contribution of 75% of the participant's contribution. See note 20 for a description of Hudbay's pension plans and note 21 for Hudbay's other employee benefit plans. (g) Net finance expenses Year ended December 31, 2020 2019 Net interest expense on long-term debt Interest expense on long-term debt $ 82,712 $ 78,265 Interest capitalized — (9,890 ) 82,712 68,375 Accretion on streaming arrangements (note 18) Current year additions 60,362 63,725 Variable consideration adjustments - prior periods (3,692 ) 6,047 56,670 69,772 Change in fair value of financial assets and liabilities at fair value through profit or loss Embedded derivatives (45,387 ) 3,708 Gold prepayment liability 20,141 — Investments (4,124 ) 4,539 (29,370 ) 8,247 Other net finance costs Net foreign exchange (gains) losses (1,644 ) 1,388 Accretion on community agreements measured at amortized cost 3,641 1,222 Unwinding of discounts on provisions 3,543 4,392 Withholding taxes 8,267 8,100 Premium paid on redemption of notes (note 17) 7,252 — Write-down of unamortized transaction costs (note 17) 3,817 — Other finance expense 8,826 11,027 Interest income (1,812 ) (8,527 ) 31,890 17,602 Net finance expense $ 141,902 $ 163,996 Until October 1, 2019, interest expense related to certain long-term debt had been capitalized to the Rosemont project. Following the Court ruling to vacate and remand the U.S. Forest Service's issuance of the Final Record of Decision for the Rosemont project during the third quarter of 2019, Hudbay ceased capitalization effective October 1, 2019. The capitalization of this interest expense will resume upon the reinstatement of permits and will continue from that point until commercial production is reached. Other finance expense relates primarily to fees on Hudbay's revolving credit facilities and leases.

Cash

Cash	12 Months Ended
Cash	Dec. 31, 2020
Cash and cash equivalents [abstract]
Cash [Text Block]	7. Cash Cash balances represent deposits with a maturity date of less than 3 months.

Trade and other receivables

Trade and other receivables	12 Months Ended
Trade and other receivables	Dec. 31, 2020
Trade and other receivables [abstract]
Trade and other receivables [Text Block]	8. Trade and other receivables Dec. 31, 2020 Dec. 31, 2019 Current Trade receivables $ 107,787 $ 87,332 Statutory receivables 28,445 16,543 Other receivables 4,967 2,119 141,199 105,994 Non-current Taxes receivable 16,941 17,669 Other receivables 1,627 1,595 18,568 19,264 $ 159,767 $ 125,258

Inventories

Inventories	12 Months Ended
Inventories	Dec. 31, 2020
Disclosure Of Inventories [Abstract]
Inventories [Text Block]	9. Inventories Dec. 31, 2020 Dec. 31, 2019 Current Stockpile $ 13,906 $ 10,396 Work in progress 6,364 14,420 Finished goods 72,923 62,230 Materials and supplies 49,912 51,774 143,105 138,820 Non-current Stockpile 16,704 14,626 Materials and supplies 5,302 4,829 22,006 19,455 $ 165,111 $ 158,275 The cost of inventories recognized as an expense, including depreciation, and included in cost of sales amounted to $921,895 for the year ended December 31, 2020 (year ended December 31, 2019 - $978,810). During the year ended December 31, 2020, Hudbay recognized a net expense of $32 in cost of sales related to adjustments of the carrying value of inventories to net realizable value (year ended December 31, 2019 - $504). Adjustments to the carrying value of inventories to net realizable value were related to changes in commodity prices.

Other financial assets

Other financial assets	12 Months Ended
Other financial assets	Dec. 31, 2020
Disclosure of financial assets [abstract]
Other financial assets [Text Block]	10. Other financial assets Dec. 31, 2020 Dec. 31, 2019 Current Derivative assets $ 2,736 $ 1,712 Restricted cash 337 337 3,073 2,049 Non-current Investments at fair value through profit or loss 15,669 11,287 $ 18,742 $ 13,336 Investments at fair value through profit or loss consist of securities in Canadian metals and mining companies, all of which are publicly traded. The change in investments at fair value through profit or loss is mostly attributed to fluctuations in market price and foreign exchange impact.

Intangibles and other assets

Intangibles and other assets	12 Months Ended
Intangibles and other assets	Dec. 31, 2020
Disclosure of detailed information about intangible assets [abstract]
Intangibles and other assets [Text Block]	11. Intangibles and other assets Intangibles and other assets of $21,173 includes $15,764 of other assets (December 31, 2019 - $5,384) and $5,409 of intangibles (December 31, 2019 - $5,027). Other assets represent the carrying value of certain future community costs. The liability remaining for these agreements is recorded in other financial liabilities at amortized cost (note 15)). Amortization of the carrying amount is recorded in the consolidated income statements within other expenses (note 6d) or exploration expense, depending on the nature of the agreement. The increase in other assets during the year ended December 31, 2020 primarily relates to amendments to the original agreements with communities for the Constancia operation which allow Hudbay to extract minerals over the useful life of the Constancia operation. Intangibles mainly represent computer software costs. Dec. 31, 2020 Dec. 31, 2019 Cost Balance, beginning of year $ 21,538 $ 18,557 Additions 1,466 2,325 Disposals — (96 ) Effects of movement in exchange rates 346 752 Balance, end of year 23,350 21,538 Accumulated amortization Balance, beginning of year 16,511 14,395 Additions 1,138 1,606 Disposals — (96 ) Effects of movement in exchange rates 292 606 Balance, end of year 17,941 16,511 Intangibles, net book value $ 5,409 $

Property, plant and equipment

Property, plant and equipment	12 Months Ended
Property, plant and equipment	Dec. 31, 2020
Disclosure of detailed information about property, plant and equipment [abstract]
Property, plant and equipment [Text Block]	12. Property, plant and equipment Dec. 31, 2020 Exploration and evaluation assets Capital works in progress Mining properties Plant and equipment Plant and equipment- ROU assets Total Balance, Jan. 1, 2020 $ 69,903 $ 733,874 $ 2,146,583 $ 2,653,752 $ 201,972 $ 5,806,084 Additions 809 256,251 311 28,523 17,759 303,653 Capitalized stripping and development — — 83,137 — — 83,137 Decommissioning and restoration — 263 6,849 39,680 — 46,792 Interest capitalized — — — — — — Transfers and other movements 8,040 (36,668 ) (41,256 ) 70,777 (893 ) — Disposals — — — (19,681 ) (5,884 ) (25,565 ) Effects of movements in exchange rates 307 3,442 21,837 20,668 1,349 47,603 Balance, Dec. 31, 2020 79,059 957,162 2,217,461 2,793,719 214,303 6,261,704 Accumulated depreciation Balance, Jan. 1, 2020 — — 963,530 1,069,687 110,308 2,143,525 Depreciation for the year — — 146,113 200,632 23,351 370,096 Disposals — — — (14,038 ) (2,475 ) (16,513 ) Effects of movement in exchange rates — — 16,631 15,300 1,010 32,941 Balance, Dec. 31, 2020 — — 1,126,274 1,271,581 132,194 2,530,049 Net book value $ 79,059 $ 957,162 $ 1,091,187 $ 1,522,138 $ 82,109 $ 3,731,655 Dec. 31, 2019 Exploration and evaluation assets Capital works in progress Mining properties Plant and equipment Plant and equipment- ROU assets 1 Total Balance, January 1, 2019 $ 52,206 $ 873,781 $ 1,998,439 $ 2,473,176 $ 180,151 $ 5,577,753 Additions 17,016 109,372 — 33,309 22,158 181,855 Acquisitions (note 5) — 91,332 3,157 — 373 94,862 Capitalized stripping and development — — 103,108 — — 103,108 Decommissioning and restoration — 41 3,314 86,053 — 89,408 Interest capitalized — 9,890 — — — 9,890 Transfers and other movements — (30,000 ) 642 30,406 (1,048 ) — Impairments (note 6e) — (322,249 ) — — — (322,249 ) Disposals — (2,029 ) — (10,747 ) (1,533 ) (14,309 ) Effects of movements in exchange rates 681 1,528 41,080 38,452 1,793 83,534 Other — 2,208 (3,157 ) 3,103 78 2,232 Balance, Dec. 31, 2019 69,903 733,874 2,146,583 2,653,752 201,972 5,806,084 Accumulated depreciation Balance, January 1, 2019 — — 780,754 872,330 89,877 1,742,961 Depreciation for the year — — 154,970 179,062 19,850 353,882 Disposals — — — (6,675 ) — (6,675 ) Effects of movement in exchange rates — — 27,806 24,970 581 53,357 Balance, Dec. 31, 2019 — — 963,530 1,069,687 110,308 2,143,525 Net book value $ 69,903 $ 733,874 $ 1,183,053 $ 1,584,065 $ 91,664 $ 3,662,559 At December 31, 2019 capital works in progress decreased compared to January 1, 2019 as a result of the impairment charge of $322,249 (pre-tax) related to the Arizona CGU (see note 6e), partially offset by fixed asset additions. For the impairment test completed at September 30, 2019, Fair Value Less Cost of Disposal, ("FVLCD") was used to determine the recoverable amount since it is higher than value in use. FVLCD was calculated using discounted after-tax cash flows based on cash flow projections and assumptions in Hudbay's most current life of mine ("LOM") plans. The fair value measurement in its entirety is categorized as Level 3 based on the degree to which fair value inputs are observable and have a significant effect on the recorded fair value. LOM plans are based on optimized mine and processing plans and the assessment of capital expenditure requirements of a mine site. LOM plans incorporate management's best estimates of key assumptions which are discount rates, future commodity prices, production based on current estimates of recoverable reserves, future operating and capital costs, value of mineral resources not included in the LOM plan, beginning date of project cash flows incorporating permit related project delays and future foreign exchange rates. The discount rate was based on the CGU's weighted average cost of capital, of which the two main components are the cost of equity and the after-tax cost of debt. Cost of equity was calculated based on the capital asset pricing model, incorporating the risk-free rate of return based on the US Government's marketable bond yields as at the valuation date, the Company's beta coefficient adjustment to the market equity risk premium based on the volatility of the Company's return in relation to that of a comparable market portfolio, plus a country risk premium, size premium and company-specific risk factor. Cost of debt was determined by applying an appropriate market indication of the Company's borrowing capabilities and the corporate income tax rate applicable to the Arizona CGU. As at September 30, 2019, a real discount rate of 9.50% for the Arizona CGU was used to calculate the estimated after-tax discounted future net cash flows, commensurate with its individual estimated level of risk. Commodity prices used in the impairment assessment were determined by reference to external market participant sources. The key commodity price for this assessment is the price of copper. Where applicable to each of Hudbay's CGUs, the cash flow calculations were based on estimates of future production levels applying forecasts for metal prices, which included forecasts for long-term prices. As at September 30, 2019, for the Arizona CGU, the cash flow calculations utilized a long-term copper price of $3.10/lb, molybdenum long-term prices of $11.00/lb and capital, operating and reclamation costs based on the most current LOM plans. Expected future cash flows used to determine the FVLCD used in the impairment testing are inherently uncertain and could materially change over time. Should management's estimate of the future not reflect actual events, impairments may be identified. This may have a material effect on the Company's consolidated financial statements. Although it is reasonably possible for a change in key assumptions to occur, the possible effects of a change in any single assumption may not fairly reflect the impact on a CGU's fair value as the assumptions are inextricably linked. For example, a decrease in the assumed price of long-term copper could result in amendments to the mine plans which would partially offset the effect of lower prices. It is difficult to determine how all of these factors would interrelate; however, in deriving a recoverable amount, management believes all of these factors need to be considered. As at September 30, 2019, the carrying value of the Arizona CGU exceeded the estimated recoverable amount of $615,368 by $242,106 (after-tax), leading to the impairment charge recorded (note 6e). At December 31, 2020, the Company assessed whether there were impairment or impairment reversal indicators associated the general business environment and known changes to business planning and determined there were none (note 6e).

Trade and other payables

Trade and other payables	12 Months Ended
Trade and other payables	Dec. 31, 2020
Trade and other payables [abstract]
Trade and other payables [Text Block]	13. Trade and other payables Dec. 31, 2020 Dec. 31, 2019 Trade payables $ 104,598 $ 68,742 Accruals and payables 72,698 80,375 Accrued interest 30,766 34,603 Exploration and evaluation payables 1,351 884 Statutory payables 23,734 7,800 $ 233,147 $ 192,404 Accruals and payables include operational and capital costs and employee benefit amounts owing.

Other liabilities

Other liabilities	12 Months Ended
Other liabilities	Dec. 31, 2020
Miscellaneous current liabilities [abstract]
Other liabilities [Text Block]	14. Other liabilities Dec. 31, 2020 Dec. 31, 2019 Current Provisions (note 19) $ 33,675 $ 33,575 Pension liability (note 20) 13,552 12,015 Other employee benefits (note 21) 3,154 2,806 Unearned revenue 1,590 1,015 $ 51,971 $ 49,411

Other financial liabilities

Other financial liabilities	12 Months Ended
Other financial liabilities	Dec. 31, 2020
Disclosure of financial liabilities [abstract]
Other financial liabilities [Text Block]	15. Other financial liabilities Dec. 31, 2020 Dec. 31, 2019 Current Derivative liabilities $ 15,312 $ 10,295 Embedded derivatives (note 27d) — 9,074 Other financial liabilities at amortized cost 9,401 8,707 24,713 28,076 Non-current Deferred Rosemont acquisition consideration 25,961 24,491 Gold prepayment liability 137,031 — Other financial liabilities at amortized cost 31,386 15,293 194,378 39,784 $ 219,091 $ 67,860 The derivative liabilities include derivative and hedging transactions. Derivative liabilities are carried at their fair value with changes in fair value recorded to the consolidated income statements. The fair value adjustments for hedging type derivatives are recorded in revenue. Fair value adjustments for embedded derivatives are recorded within net finance expense. On May 7, 2020, the Company entered into an agreement and received $115,005 in exchange for the delivery of 79,954 gold ounces starting January 2022 and ending in December 2023, which were valued at gold forward curve prices averaging $1,682 per ounce at the time of the transaction. The agreement has been assessed as a financial liability that has been designated as fair value through profit or loss within change in fair value of financial instruments, with a component of the fair value related to the fluctuation in the Company's own credit risk being recorded to other comprehensive income. The fair value adjustment recorded in profit or loss and other comprehensive income for the year ended December 31, 2020 totaled loss of $22,026. Other financial liabilities at amortized cost relate to agreements with communities near the Constancia operation which allow Hudbay to extract minerals over the useful life of the Constancia operation, carry out exploration and evaluation activities in the area and provide Hudbay with community support to operate in the region. The changes in other financial liabilities at amortized cost during the year ended December 31, 2020 primarily relates to changes in estimated community payments arising from the execution of the Pampacancha surface rights agreement and individual land user agreements with certain community members, partially offset by disbursements. The following table summarizes changes in other financial liabilities at amortized cost: Balance, January 1, 2019 $ 21,361 Net additions 7,369 Disbursements (6,351 ) Accretion 1,222 Effects of changes in foreign exchange 399 Balance, December 31, 2019 $ 24,000 Net additions 116,233 Disbursements (98,375 ) Accretion 3,641 Effects of changes in foreign exchange (4,712 ) Balance, December 31, 2020 $ 40,787

Lease Liability

Lease Liability	12 Months Ended
Lease Liability	Dec. 31, 2020
Lease liabilities [abstract]
Lease Liability [Text Block]	16. Lease Liability Balance, January 1, 2019 $ 89,215 Additional capitalized leases (note 12) 22,158 Lease payments (32,952 ) Accretion and other movements 3,526 Balance, December 31, 2019 $ 81,947 Additional capitalized leases (note 12) 17,759 Lease payments (35,980 ) Accretion and other movements (212 ) Balance, December 31, 2020 $ 63,514 Dec. 31, 2020 Dec. 31, 2019 Current $ 33,473 $ 32,781 Non-current 30,041 49,166 $ 63,514 $ 81,947 Hudbay has entered into leases for its Peru, Manitoba and Arizona business units which expire between 2020 and 2043. The interest rates on leases which were capitalized have interest rates between 1.95% to 5.44%, per annum. The range of interest rates utilized for discounting varies depending mostly on the Hudbay entity acting as lessee and duration of the lease. For certain leases, Hudbay has the option to purchase the equipment and vehicles leased at the end of the terms of the leases. Hudbay's obligations under these leases are secured by the lessor's title to the leased assets. The present value of applicable lease payments has been recognized as a ROU asset, which was included as a non-cash addition to property, plant and equipment, and a corresponding amount as a lease liability. There are no restrictions placed on Hudbay by entering into these leases. The following outlines expenses recognized within the Company's consolidated income statements for the periods ended December 31, 2020 and December 31, 2019, relating to leases for which a recognition exemption was applied. Year ended 2020 2019 Short-term leases $ 40,253 $ 45,745 Low value leases 353 92 Variable leases 57,389 56,152 Total $ 97,995 $ 101,989 Payments made for short term, low value and variable leases would mostly be captured as expenses in the consolidated income statements, however, certain amounts may be capitalized to PP&E for the Arizona business unit during its development phase and certain amounts may be reported in inventories given the timing of sales. Variable consideration leases include equipment used for heavy civil works at Constancia.

Long-term debt

Long-term debt	12 Months Ended
Long-term debt	Dec. 31, 2020
Disclosure of detailed information about borrowings [abstract]
Long-term debt [text block]	17. Long-term debt Long-term debt is comprised of the following: Dec. 31, 2020 Dec. 31, 2019 Senior unsecured notes (a) $ 1,139,695 $ 991,558 Less: Unamortized transaction costs - revolving credit facilities (b) (4,020 ) (6,303 ) $ 1,135,675 $ 985,255 (a) Senior unsecured notes Balance, January 1, 2019 $ 989,306 Change in fair value of embedded derivative (prepayment option) 1,079 Accretion of transaction costs and premiums 1,173 Balance, December 31, 2019 $ 991,558 Addition to Principal, net of $8,176 transaction costs 591,824 Principal repayments (400,000 ) Change in fair value of embedded derivative (prepayment option) (47,169 ) Write-down of unamortized transaction costs 2,315 Accretion of transaction costs and premiums 1,167 Balance, December 31, 2020 $ 1,139,695 On September 23, 2020, Hudbay completed an offering of $600,000 aggregate principal amount of 6.125% senior unsecured notes due April 2029 (the "2029 Notes"). Hudbay used the proceeds of the offering to satisfy and discharge all of its obligations with respect to its then outstanding $400,000 aggregate principal amount of 7.25% senior unsecured notes due 2023 (the "2023 Notes"). The unamortized transaction costs of $2,315 were expensed upon extinguishment of the 2023 Notes. The early redemption of these notes resulted in a charge of $7,252, which was recorded on the consolidated income statement (note 6g). As at December 31, 2020, $1,200,000 aggregate principal amount of senior notes were outstanding in two series: (i) a series of 7.625% senior notes due 2025 in an aggregate principal amount of $600,000 and (ii) a series of 6.125% senior notes due 2029 in an aggregate principal amount of $600,000. The senior notes are guaranteed on a senior unsecured basis by substantially all of the Company's subsidiaries, other than HudBay (BVI) Inc. and certain excluded subsidiaries, which include the Company's subsidiaries that own an interest in the Rosemont project and any newly formed or acquired subsidiaries that primarily hold or may develop non-producing mineral assets that are in the pre-construction phase of development. (b) Unamortized transaction costs - revolving credit facilities Balance, January 1, 2019 $ 8,276 Accretion of transaction costs (2,342 ) Transaction costs 369 Balance, December 31, 2019 $ 6,303 Accretion of transaction costs (3,062 ) Write-down of unamortized transaction costs (1,502 ) Transaction costs 2,281 Balance, December 31, 2020 1 $ 4,020 1 On August 31, 2020, Hudbay completed a restructuring of its two senior secured credit facilities. The total available credit has been reduced from $550,000 to $400,000 and various financial covenants have been amended. The unamortized transaction costs of $1,502 were expensed upon restructuring of the credit facilities. As at December 31, 2020, the Peru business unit had $24,796 in letters of credit issued under the Peru revolving credit facility to support its reclamation obligations and the Manitoba business unit had $90,295 in letters of credit issued under the Canada revolving credit facility to support its reclamation and pension obligations. As at December 31, 2020, there were no cash advances under the credit facilities. Surety bonds The Arizona business unit had $8,591 in surety bonds and the Peru business unit had $20,000 in surety bonds, issued to support future reclamation and closure obligations. No cash collateral is required to be posted under these surety bonds. Other letters of credit The Peru business unit had $45,000 in letters of credit issued with various Peruvian financial institutions. No cash collateral is required to be posted under these letters of credit.

Deferred revenue

Deferred revenue	12 Months Ended
Deferred revenue	Dec. 31, 2020
Disclosure Of Deferred Revenue [Abstract]
Deferred revenue [Text Block]	18. Deferred revenue On August 8, 2012 and November 4, 2013, Hudbay entered into precious metals stream transactions with Wheaton whereby Hudbay has received aggregate deposit payments of $455,100 In addition to the aggregate deposit payments of $885,000, as gold and silver is delivered under the stream agreements, Hudbay receives cash payments equal to the lesser of (i) the market price and (ii) $400 per ounce (for gold) and $5.90 per ounce (for silver), subject to 1% annual escalation after three years, from the inception of the agreement. Hudbay recorded the deposits received as deferred revenue and recognizes amounts in revenue as gold and silver are delivered under the stream agreements. Hudbay determines the amortization of deferred revenue to the consolidated income statements on a per unit basis using the estimated total number of gold and silver ounces expected to be delivered under the stream agreements over the life of the 777 and Constancia life-of-mine plans. During the third quarter of 2020, Hudbay revised its estimate of remaining mineralization for the 777 deposit and as such adjusted the drawdown rates for the remainder of the year. For the year ended December 31, 2020 the drawdown rates for the 777 stream agreement for gold and silver were $1,173 and $22.43 per ounce, respectively (year ended December 31, 2019 - $1,177 and $22.51 per ounce, respectively). For the year ended December 31, 2020 the drawdown rates for the Constancia stream agreement for gold and silver were $976 and $21.52 per ounce, respectively (year ended December 31, 2019 - $948 and $21.77 per ounce, respectively). Hudbay estimates the current portion of deferred revenue based on deliveries anticipated over the next twelve months. Hudbay has determined that precious metals stream contracts are subject to variable consideration and contain a significant financing component. As such, the Company recognizes a financing charge at each reporting period and will gross up the deferred revenue balance to recognize the significant financing element that is part of these contracts. Hudbay's streaming arrangements are secured against the mining properties and other business unit assets associated with the applicable stream. Hudbay expects that the remaining performance obligations for the 777 and Constancia streams will be settled by the expiry of their respective stream agreements, which is no earlier than 2052. As part of the streaming agreement for the 777 mine, Hudbay must repay, with precious metals credits, the legal deposit provided by August 1, 2052, the expiry date of the agreement. If the legal deposit is not fully repaid with precious metals credits from 777 production by the expiry date, a cash payment for the remaining amount will be due at the expiry date of the agreement. Given the mineral reserve and resources of the 777 mine and the current mine plan, there is a possibility that an amount of the legal deposit may not be repaid by means of 777 mine's precious metals credits over its expected remaining mine life. As at December 31, 2020, this prepayment amount does not meet the definition of a financial liability. Hudbay incorporates the possibility of repayment as part of its assessment of variable consideration in recognizing the amount of deferred revenue to recognize in income. The following table summarizes changes in deferred revenue: Balance, January 1, 2019 $ 566,078 Amortization of deferred revenue Liability drawdown (92,398 ) Variable consideration adjustments - prior periods 16,295 Accretion on streaming arrangements Current year additions 63,725 Variable consideration adjustments - prior periods 6,047 Effects of changes in foreign exchange 4,009 Balance, December 31, 2019 $ 563,756 Amortization of deferred revenue Liability drawdown (67,263 ) Variable consideration adjustments - prior periods (6,668 ) Accretion on streaming arrangements (note 6g) Current year additions 60,362 Variable consideration adjustments - prior periods (3,692 ) Effects of changes in foreign exchange 189 Balance, December 31, 2020 $ 546,684 Consideration from the Company's stream agreement is considered variable. Gold and silver stream revenue can be subject to cumulative adjustments when the number of ounces to be delivered under the contract changes. As a result of changes in the Company's mineral reserve and resource estimate in the first quarter of 2020 and amendments made to the 777 mine plan in the third quarter of 2020, the amortization rate by which deferred revenue is drawn down into income was adjusted and, as required, a current period catch up adjustment is made for all prior period stream revenues since the stream agreement inception date. This variable consideration adjustment resulted in an increase in revenue of $6,668 and reversal of finance expense of $3,692 for the year ended December 31, 2020 (December 31, 2019 - revenue reversal of $16,295 and additional finance expense $6,047). During the year ended December 31, 2020, the Company recognized an adjustment to gold and silver revenue and finance costs due to a net increase in the Company's mineral reserve and resources estimates coupled with a change to the 777 mine plan. During the year ended December 31, 2019 the Company recognized an adjustment to gold and silver revenue and finance costs. Deferred revenue is reflected in the consolidated balance sheets as follows: Dec. 31, 2020 Dec. 31, 2019 Current $ 102,782 $ 86,933 Non-current 443,902 476,823 $ 546,684 $ 563,756

Provisions

Provisions	12 Months Ended
Provisions	Dec. 31, 2020
Disclosure of other provisions [abstract]
Provisions [Text Block]	19. Provisions Decommis- sioning, restoration and similar liabilities Deferred share units (note 24a) Restricted share units 1 (note 24a) Performan- ce share units (note 24a) Other Total Balance, January 1, 2020 $ 302,116 $ 3,876 $ 5,477 $ — $ 2,956 $ 314,425 Net additional provisions made 5,868 1,628 3,642 1,257 15 12,410 Amounts used (18,737 ) (497 ) (2,646 ) — (1,824 ) (23,704 ) Unwinding of discount (note 6g) 3,543 — — — — 3,543 Effect of change in discount rate 43,180 — — — — 43,180 Effect of foreign exchange 7,162 191 116 43 (3 ) 7,509 Effect of change in share price — 3,521 3,860 730 — 8,111 Balance, December 31, 2020 $ 343,132 $ 8,719 $ 10,449 $ 2,030 $ 1,144 $ 365,474 1 Provisions are reflected in the consolidated balance sheets as follows: December 31, 2020 Decommis-sioning, restoration and similar liabilities Deferred share units (note 24a) Restricted share units 1 (note 24a) Performance share units (note 24a) Other Total Current (note 14) $ 20,308 $ 8,719 $ 4,648 $ — $ — $ 33,675 Non-current 322,824 — 5,801 2,030 1,144 331,799 $ 343,132 $ 8,719 $ 10,449 $ 2,030 $ 1,144 $ 365,474 Decommis-sioning, restoration and similar liabilities Deferred share units (note 24a) Restricted share units 1 Performance share units (note 24a) Other Total Balance, January 1, 2019 $ 202,024 $ 4,288 $ 12,201 $ — $ 411 $ 218,924 Net additional provisions made 68,881 1,479 2,885 — 2,882 76,127 Amounts used (4,136 ) (1,668 ) (9,380 ) — (341 ) (15,525 ) Unwinding of discount (note 6g) 4,392 — — — — 4,392 Effect of change in discount rate 23,635 — — — — 23,635 Effect of foreign exchange 7,320 99 225 — 4 7,648 Effect of change in share price — (322 ) (454 ) — — (776 ) Balance, December 31, 2019 $ 302,116 $ 3,876 $ 5,477 $ — $ 2,956 $ 314,425 1 December 31, 2019 Decommis- sioning, restoration and similar liabilities Deferred share units (note 24a) Restricted share units1 (note 24a) Performan- ce share units (note 24a) Other Total Current (note 14) $ 23,621 $ 3,876 $ 4,468 $ — $ 1,610 $ 33,575 Non-current 278,495 — 1,009 — 1,346 280,850 $ 302,116 $ 3,876 $ 5,477 $ — $ 2,956 $ 314,425 Decommissioning, restoration and similar liabilities are remeasured at each reporting date to reflect changes in discount rates, which can significantly affect the liabilities. Decommissioning, restoration and similar liabilities Hudbay's decommissioning, restoration and similar liabilities relate to the rehabilitation and closure of currently operating mines and metallurgical plants, development-phase properties and closed properties. The amount of the provision has been recorded based on estimates and assumptions that management believes are reasonable; however, actual decommissioning and restoration costs may differ from expectations. During the year ended December 31, 2020, additional provisions were recognized mostly as a result of lower discount rates and increased cost in Peru and Manitoba as well as additional disturbance in Peru. During 2019, additional provisions were recognized as a result of higher estimates for closure activities of tailings facilities at the Manitoba operations to ensure compliance with higher industry-wide standards for tailings management safety and, to a lesser extent, increased mine activity footprints and the resulting higher disturbance at the Constancia operation. Hudbay's decommissioning and restoration liabilities relate mainly to its Manitoba operations. Management anticipates that the assets in Flin Flon will be placed on care and maintenance once mining activities are completed at 777 mine in order to maintain optionality for restart should a new mine be found in the Flin Flon area. The majority of closure activities will occur once all mining activities in Manitoba are completed. These provisions also reflect estimated post-closure cash flows that extend to the year 2100 for ongoing monitoring and water treatment requirements. Management anticipates most decommissioning and restoration activities for the Constancia operation will occur from 2035 to 2070, which include ongoing monitoring and water treatment requirements. These estimates have been discounted to their present value at rates ranging from 0.12% to 1.65% per annum (2019 - 1.59% to 2.39%), using pre-tax risk-free interest rates that reflect the estimated maturity of each specific liability.

Pension obligations

Pension obligations	12 Months Ended
Pension obligations	Dec. 31, 2020
Pension Obligations [Abstract]
Pension obligations [Text Block]	20. Pension obligations Hudbay maintains non-contributory and contributory defined benefit pension plans for certain of its employees. The Company uses a December 31 measurement date for all of its plans. For Hudbay's significant plans, the most recent actuarial valuations filed for funding purposes were performed during 2020 using data as at December 31, 2019. For these plans, the next actuarial valuation required for funding purposes will be performed during 2021 using data as of December 31, 2020. Movements in the present value of the defined benefit obligation in the current and previous years were as follows: Year ended Dec. 31, 2020 Dec. 31, 2019 Opening defined benefit obligation: $ 243,733 $ 211,512 Current service costs 11,044 9,880 Interest cost 6,569 7,156 Benefits paid from plan (35,384 ) (16,745 ) Benefits paid from employer (1,317 ) (934 ) Participant contributions 48 64 Effects of movements in exchange rates 2,780 11,660 Remeasurement actuarial (gains)/losses: Arising from changes in demographic assumptions (1,461 ) — Arising from changes in financial assumptions 16,967 29,609 Arising from experience adjustments (2,625 ) (2,258 ) Settlement payments from plan assets — (6,307 ) Loss on settlement — 96 Closing defined benefit obligation $ 240,354 $ 243,733 The defined benefit obligation closing balance, by member group, is as follows: Dec. 31, 2020 Dec. 31, 2019 Active members $ 211,861 $ 231,959 Deferred members 2,198 1,555 Retired members 26,295 10,219 Closing defined benefit obligation $ 240,354 $ 243,733 Movements in the fair value of the pension plan assets in the current and previous years were as follows: Year ended Dec. 31, 2020 Dec. 31, 2019 Opening fair value of plan assets: $ 202,119 $ 175,795 Interest income 5,695 6,170 Remeasurement adjustment: Return on plan assets (excluding amounts included in net interest expense) 15,377 21,460 Contributions from the employer 12,987 11,952 Employer direct benefit payments 1,317 934 Contributions from plan participants 48 64 Benefit payment from employer (1,317 ) (934 ) Administrative expenses paid from plan assets (77 ) (82 ) Benefits paid (35,384 ) (16,745 ) Settlement payments from plan assets — (6,307 ) Effects of changes in foreign exchange rates 2,721 9,812 Closing fair value of plan assets $ 203,486 $ 202,119 The amount included in the consolidated balance sheets arising from the entity's obligation in respect of its defined benefit plans is as follows: Dec. 31, 2020 Dec. 31, 2019 Present value of funded defined benefit obligation $ 220,210 $ 224,364 Fair value of plan assets (203,486 ) (202,119 ) Present value of unfunded defined benefit obligation 20,144 19,369 Net liability arising from defined benefit obligation $ 36,868 $ 41,614 Reflected in the consolidated balance sheets as follows: Dec. 31, 2020 Dec. 31, 2019 Pension obligation - current (note 14) $ 13,552 $ 12,015 Pension obligation - non-current 23,316 29,599 Total pension obligation $ 36,868 $ 41,614 Pension expense is as follows: Dec. 31, 2020 Dec. 31, 2019 Service costs: Current service cost $ 11,044 $ 9,880 Loss on settlement — 96 Total service cost 11,044 9,976 Net interest expense 874 986 Administration cost 77 82 Defined benefit pension expense $ 11,995 $ 11,044 Defined contribution pension expense $ 1,791 $ 1,639 Remeasurement on the net defined benefit liability: Dec. 31, 2020 Dec. 31, 2019 Return on plan assets (excluding amounts included in net interest expense) $ (15,377 ) $ (21,460 ) Actuarial gains arising from changes in demographic assumptions (1,461 ) — Actuarial losses arising from changes in financial assumptions 16,967 29,609 Actuarial gains arising from experience adjustments (2,625 ) (2,258 ) Defined benefit (gain)/loss related to remeasurement $ (2,496 ) $ 5,891 Total pension cost $ 11,290 $ 18,574 Pension amounts recognized include those directly related to production of inventory; such amounts are recognized initially as costs of inventory and are expensed in the consolidated income statements within cost of sales upon sale of the inventory. The current service cost, the interest cost and administration cost for the year are included in the employee benefits expense. The remeasurement of the net defined benefit liability is included in OCI. The defined benefit pension plans typically expose Hudbay to actuarial risks such as: investment risk, interest rate risk, longevity risk and salary risk. Investment risk The present value of the liabilities for the defined benefit plans is calculated using a discount rate determined by reference to high quality corporate bond yields; if the return on plan assets is below this rate, it will create a plan deficit. Hudbay's primary quantitative investment objectives are maximization of the long term real rate of return, subject to an acceptable degree of investment risk and preservation of principal. Risk tolerance is established through consideration of several factors including past performance, current market condition and the funded status of the plan. Interest risk A decrease in the bond interest rate will increase the pension plan liabilities; however, this will be partially offset by an increase in the return on the plan's debt investments. Longevity risk The present value of the defined benefit plans liabilities is calculated by reference to the best estimate of the mortality of plan participants both during and after their employment. An increase in the life expectancy of the plan participants will increase the pension plans liabilities. Salary risk The present value of the defined benefit plans liabilities for some of the pension plans is calculated by reference to the future salaries of plan participants. As such, an increase in the salary of the plan participants will increase the plans' liabilities. The principal assumptions used for the purposes of the actuarial valuations were as follows: 2020 2019 Defined benefit cost: Discount rate - benefit obligations 3.08 % 3.73 % Discount rate - service cost 3.10 % 3.75 % Expected rate of salary increase 1 2.75 % 2.75 % Average longevity at retirement age for current pensioners (years) 2 Males 21.2 21.1 Females 23.9 23.9 Defined benefit obligation: Discount rate 2.54 % 3.08 % Expected rate of salary increase 1 2.75 % 2.75 % Average longevity at retirement age for current pensioners (years) 2 Males 20.3 21.2 Females 23.7 23.9 Average longevity at retirement age for current employees (future pensioners) (years) 2 Males 22.2 23.0 Females 25.4 25.6 1 2 Hudbay reviews the assumptions used to measure pension costs (including the discount rate) on an annual basis. Economic and market conditions at the measurement date affect these assumptions from year to year. In determining the discount rate, Hudbay considers the duration of the pension plan liabilities. Significant actuarial assumptions for the determination of the defined benefit obligation are discount rate, expected salary increase and mortality. The sensitivity analysis below has been determined based on reasonably possible changes of the respective assumptions occurring at the end of the reporting periods, while holding other assumptions constant: — — — The sensitivity analysis presented above may not be representative of the actual change in the defined benefit obligation as it is unlikely that the change in assumptions would occur in isolation of one another as some of the assumptions may be correlated. Furthermore, in presenting the above sensitivity analysis, the present value of the defined benefit obligation has been calculated using the projected unit credit method at the end of the reporting period, which is the same as that applied in calculating the defined benefit obligation liability recognized in the consolidated balance sheets. The Company's main pension plans are registered federally with the Office of the Superintendent of Financial Institution and with the Canada Revenue Agency. The registered pension plans are governed in accordance with the Pension Benefits Standards Act and the Income Tax Act. The sponsor contributes the amount needed to maintain adequate funding as dictated by the prevailing regulations. Expected employer contribution to the pension plans for the fiscal year ending December 31, 2021 is $12,437. The average duration of the pension obligation at December 31, 2020 is 21.2 years (2019 - 19.3 years). This number can be broken down as follows: — — — Asset-Liability-Matching studies are performed periodically to analyze the investment policies in terms of risk and-return profiles. The actual return on plan assets in 2020 was 10.8% (2019: 15.1%). The pension plans do not invest directly in either securities or property/real estate of the Company. With the exception of fixed income investments and certain equity instruments, the plan assets are actively managed by investment managers, with the goal of attaining returns that potentially outperform passively managed investments. Within appropriate limits, the actual composition of the invested funds may vary from the prescribed investment mix. The following is a summary of the fair value classification levels for investment: December 31, 2020 Level 1 Level 2 Level 3 Total Investments: Money market instruments $ 4,766 $ — $ — $ 4,766 Pooled equity funds 68,926 — — 68,926 Pooled fixed income funds — 98,922 — 98,922 Alternative investment funds — 30,323 — 30,323 Balanced funds — 549 — 549 $ 73,692 $ 129,794 $ — $ 203,486 December 31, 2019 Level 1 Level 2 Level 3 Total Investments: Money market instruments $ 1,588 $ — $ — $ 1,588 Pooled equity funds 76,680 — — 76,680 Pooled fixed income funds — 103,646 — 103,646 Alternative investment funds — 19,438 — 19,438 Balanced funds — 767 — 767 $ 78,268 $ 123,851 $ — $ 202,119

Other employee benefits

Other employee benefits	12 Months Ended
Other employee benefits	Dec. 31, 2020
Other Employee Benefits [Abstract]
Other employee benefits [Text Block]	21. Other employee benefits Hudbay sponsors both other long-term employee benefit plans and non-pension post-employment benefits plans and uses a December 31 measurement date. These obligations relate mainly to commitments for post-retirement health benefits. Information about Hudbay's post-employment and other long-term employee benefits is as follows: Movements in the present value of the defined benefit obligation in the current and previous years were: Year ended Dec. 31, 2020 Dec. 31, 2019 Opening defined benefit obligation $ 116,696 $ 93,528 Current service cost 1 4,140 3,060 Past service cost — — Interest cost 3,478 3,600 Effects of movements in exchange rates 2,423 4,864 Remeasurement actuarial (gains)/losses: Arising from changes in demographic assumptions (4,460 ) — Arising from changes in financial assumptions 10,043 14,094 Arising from experience adjustments (489 ) 87 Benefits paid (2,215 ) (2,537 ) Closing defined benefit obligation $ 129,616 $ 116,696 1 The defined benefit obligation closing balance, by group member, is as follows: Dec. 31, 2020 Dec. 31, 2019 Active members $ 68,983 $ 60,801 Inactive members 60,633 55,895 Closing defined benefit obligation $ 129,616 $ 116,696 Movements in the fair value of defined benefit amounts in the current and previous years were as follows: Dec. 31, 2020 Dec. 31, 2019 Employer contributions $ 2,215 $ 2,537 Benefits paid (2,215 ) (2,537 ) Closing fair value of assets $ — $ — The non-pension employee benefit plan obligations are unfunded. Reconciliation of assets and liabilities recognized in the consolidated balance sheets: Dec. 31, 2020 Dec. 31, 2019 Unfunded benefit obligation $ 129,616 $ 116,696 Vacation accrual and other - non-current 3,046 2,888 Net liability $ 132,662 $ 119,584 Reflected in the consolidated balance sheets as follows: Dec. 31, 2020 Dec. 31, 2019 Other employee benefits liability - current (note 14) $ 3,154 $ 2,806 Other employee benefits liability - non-current 129,508 116,778 Net liability $ 132,662 $ 119,584 Other employee future benefit expense includes the following: Dec. 31, 2020 Dec. 31, 2019 Current service cost 1 $ 4,140 $ 3,060 Net interest cost 3,478 3,600 Components recognized in consolidated income statements $ 7,618 $ 6,660 1 Dec. 31, 2020 Dec. 31, 2019 Remeasurement on the net defined benefit liability: Actuarial gains arising from changes in demographic assumptions $ (4,460 ) $ — Actuarial losses arising from changes in financial assumptions 10,043 14,094 Actuarial (gains)/losses arising from changes experience adjustments (489 ) 87 Components recognized in statements of comprehensive income $ 5,094 $ 14,181 Total other employee future benefit cost $ 12,712 $ 20,841 Other employee benefit amounts recognized include those directly related to production of inventory; such amounts are recognized initially as costs of inventory and are expensed in the consolidated income statements within cost of sales upon sale of the inventory. Dec. 31, 2020 Dec. 31, 2019 Defined benefit cost: Discount rate 3.17 % 3.88 % Initial weighted average health care trend rate 5.68 % 5.74 % Ultimate weighted average health care trend rate 4.00 % 4.00 % Average longevity at retirement age for current pensioners (years) 1 Males 21.2 21.1 Females 23.9 23.9 Dec. 31, 2020 Dec. 31, 2019 Defined benefit obligation: Discount rate 2.76 % 3.17 % Initial weighted average health care trend rate 5.66 % 5.68 % Ultimate weighted average health care trend rate 4.00 % 4.00 % Average longevity at retirement age for current pensioners (years) 1 Males 20.3 21.2 Females 23.7 23.9 Average longevity at retirement age for current employees (future pensioners) (years) 1 Males 22.2 23.1 Females 25.4 25.6 1 Hudbay reviews the assumptions used to measure other employee benefit costs (including the discount rate) on an annual basis. The other employee benefit costs typically expose Hudbay to actuarial risks such as: interest rate risk, health care cost inflation risk and longevity risk. Interest risk A decrease in the bond interest rate will increase the plan liabilities. Health care cost inflation risk The majority of the plan's benefit obligations are linked to health care cost inflation and higher inflation will lead to higher liabilities. Longevity risk The majority of the plans' benefit liability is calculated by reference to the best estimate of the mortality of plan participants both during and after their employment. An increase in the life expectancy of the plan participants will increase the plans liabilities. This is particularly significant for benefits subject to health care cost inflation where increases in inflation result in higher sensitivity to changes in life expectancy. The sensitivity analyses below have been determined based on reasonably possible changes of the respective assumptions occurring at the end of the reporting period, while holding other assumptions constant: — — — The average duration of the non-pension post-employment obligation at December 31, 2020 is 19.4 years (2019: 19.6 years). This number can be broken down as follows: — —

Income and mining taxes

Income and mining taxes	12 Months Ended
Income and mining taxes	Dec. 31, 2020
Major components of tax expense (income) [abstract]
Income and mining taxes [Text Block]	22. Income and mining taxes (a) Tax recoveries: The tax expense (recoveries) is applicable as follows: Year ended 2020 2019 Current: Income taxes $ 4,458 $ 24,919 Mining taxes 4,671 4,720 Adjustments in respect of prior years (398 ) 6,273 8,731 35,912 Deferred: Income tax recoveries - origination, revaluation and/or reversal of temporary differences (39,411 ) (133,468 ) Mining tax recoveries - origination, revaluation and/or reversal of temporary difference (3,331 ) (12,214 ) Adjustments in respect of prior years (494 ) 817 (43,236 ) (144,865 ) $ (34,505 ) $ (108,953 ) Adjustments in respect of prior years refers to amounts changing due to the filing of tax returns and assessments from government authorities. (b) Deferred tax assets and liabilities as represented on the consolidated balance sheets: Dec. 31, 2020 Dec. 31, 2019 Deferred income tax asset $ 94,070 $ 69,950 Deferred mining tax asset 7,829 5,096 101,899 75,046 Deferred income tax liability (220,568 ) (233,218 ) Deferred mining tax liability (8,865 ) (9,710 ) (229,433 ) (242,928 ) Net deferred tax liability balance, end of year $ (127,534 ) $ (167,882 ) (c) Changes in deferred tax assets and liabilities: Year ended Dec. 31, 2020 Year ended Net deferred tax liability balance, beginning of year $ (167,882 ) $ (308,577 ) Deferred tax recovery 43,236 144,865 OCI transactions (759 ) 1,878 Foreign currency translation on the deferred tax liability (2,129 ) (6,048 ) Net deferred tax liability balance, end of year $ (127,534 ) $ (167,882 ) (d) Reconciliation to statutory tax rate: As a result of its mining operations, the Company is subject to both income and mining taxes. Generally, most expenditures incurred are deductible in computing income tax, whereas mining tax legislation, although based on a measure of profitability from carrying on mining operations, is more restrictive in respect of the deductions permitted in computing income subject to mining tax. These restrictions include costs unrelated to mining operations as well as deductions for financing expenses, such as interest and royalties. In addition, income unrelated to carrying on mining operations is not subject to mining tax. A reconciliation between tax expense and the product of accounting profit multiplied by the Company's statutory income tax rate for the years ended December 31, 2020 and 2019 is as follows: Year ended December 31, 2020 2019 Statutory tax rate 26.3 % 27.0 % Tax recovery at statutory rate $ (47,047 ) $ (122,246 ) Effect of: Deductions related to mining taxes (1,369 ) (1,493 ) Adjusted income taxes (48,416 ) (123,739 ) Mining tax expense (recovery) 1,291 (6,674 ) (47,125 ) (130,413 ) Permanent differences related to: Capital items (160 ) 3,270 Other income tax permanent differences (1,165 ) 1,747 Impact of remeasurement on decommissioning liability 7,094 (12,018 ) Temporary income tax differences not recognized (1,827 ) (351 ) Other temporary income tax differences not recognized 2,927 2,323 Non-deductible impairment on UCM receivable — 7,041 Withholding tax on dividends — 6,826 Impact related to differences in tax rates in foreign operations 5,534 20,338 Impact of changes to statutory tax rates 2,412 (259 ) Foreign exchange on non-monetary items (3,628 ) (6,633 ) Impact related to tax assessments and tax return amendments 1,433 (824 ) Tax recovery $ (34,505 ) $ (108,953 ) A decrease in the statutory tax rate in 2020 mainly reflects a reduction in the Canadian statutory tax rate which is the result of the changes to the relevant provincial allocation factors based on income earned and expenses incurred in different Canadian jurisdictions. (e) Income tax effect of temporary differences - recognized: The tax effects of temporary differences that give rise to significant portions of the deferred tax assets and deferred tax liabilities at December 31, 2020 and 2019 are as follows: Balance sheet Income Statement Dec. 31, 2020 Dec. 31, Dec. 31, 2020 Dec. 31, Deferred income tax (liability) asset/ expense (recovery) Property, plant and equipment $ (88,368 ) $ (96,841 ) $ (8,473 ) $ 13,434 Pension obligation 9,467 11,332 1,294 (1,115 ) Other employee benefits 25,687 16,837 (8,850 ) (3,349 ) Decommissioning and restoration obligation 37,902 41,208 3,307 (33,391 ) Non-capital losses 110,374 90,446 (19,928 ) (17,976 ) Share issuance and debt cost 8,972 6,540 (2,768 ) 4,361 Embedded derivative (prepayment option) (13,137 ) (694 ) 12,443 245 Deferred revenue (809 ) (112 ) 697 (12,839 ) Other 3,982 1,234 (4,516 ) (7,755 ) Deferred income tax asset / expense (recovery) 94,070 69,950 (26,794 ) (58,385 ) Deferred income tax liability (asset)/ (recovery) expense Property, plant and equipment 292,858 259,145 33,713 (79,892 ) Other employee benefits 203 (80 ) (176 ) (320 ) Asset retirement obligations (1,588 ) (833 ) (756 ) 85 Non-capital losses (78,607 ) (28,643 ) (49,965 ) (1,269 ) Other 7,702 3,629 4,073 7,302 Deferred income tax liability/ expense (recovery) 220,568 233,218 (13,111 ) (74,094 ) Deferred income tax liability/ expense (recovery) $ (126,498 ) $ (163,268 ) $ (39,905 ) $ (132,479 ) The above reconciling items are disclosed at the tax rates that apply in the jurisdiction where they have arisen. (f) Income tax temporary differences - not recognized: The Company has not recognized a deferred tax asset in respect of the following deductible income tax temporary differences: Dec. 31, 2020 Dec. 31, 2019 Property, plant and equipment $ 46,718 $ 33,269 Capital losses 166,227 159,545 Other employee benefits 51,226 68,866 Asset retirement obligations 193,898 146,679 Non-capital losses 115,902 122,979 Temporary differences not recognized $ 573,971 $ 531,338 The deductible temporary differences excluding non-capital losses do not expire under current tax legislation. The Canadian non-capital losses were incurred between 2006 and 2020 and expire between 2026 and 2040. Hudbay incurred United States net operating losses between 2004 and 2020 which have a twenty year carry forward period. Peruvian net operating losses were incurred in 2020 which have a four year carry forward period. (g) The tax effects of temporary differences that give rise to significant portions of the deferred mining tax assets and liabilities at December 31, 2020 and 2019 are as follows: Dec. 31, 2020 Dec. 31, 2019 Canada Property, plant and equipment $ 7,829 $ 5,095 Dec. 31, 2020 Dec. 31, 2019 Peru Property, plant and equipment $ (8,865 ) $ (9,710 ) For the year ended December 31, 2020, Hudbay had unrecognized deferred mining tax assets of approximately $7,544 (December 31, 2019 - $5,361). (h) Unrecognized taxable temporary differences associated with investments: There are no taxable temporary differences associated with investments in subsidiaries, associates and joint ventures, for which a deferred tax liability has not been recognized. (i) Taxes receivable/payable: The timing of payments results in significant variances in period-to-period comparisons of the tax receivable and tax payable balances. (j) Other disclosure: The tax rules and regulations applicable to mining companies are highly complex and subject to interpretation. The Company may be subject in the future to a review of its historic income and other tax filings and, in connection with such reviews, disputes can arise with tax authorities over the interpretation or application of certain tax rules and regulations in respect of the Company's business. These reviews may alter the timing or amount of taxable income or deductions. The amount ultimately reassessed upon resolution of issues raised may differ from the amount accrued.

Share capital

Share capital	12 Months Ended
Share capital	Dec. 31, 2020
Disclosure of classes of share capital [abstract]
Share capital [Text Block]	23. Share capital (a) Preference shares: Authorized: Unlimited preference shares without par value. Issued and fully paid: Nil. (b) Common shares: Authorized: Unlimited common shares without par value. Issued and fully paid: Year ended December 31, 2020 Year ended Common shares Amount Common shares Amount Beginning and 261,272,151 $ 1,777,340 261,272,151 $ 1,777,340 During the year ended December 31, 2020, the Company declared two semi-annual dividends of C$0.01 per share each. The Company paid $1,804 and $1,979 in dividends on March 27, 2020 and September 25, 2020 to shareholders of record as of March 10, 2020 and September 4, 2020. During the year ended December 31, 2019, the Company paid $1,955 and $1,972 in dividends on March 29, 2019 and September 27, 2019 to shareholders of record as of March 8, 2019 and September 6, 2019. The Company declared a semi-annual dividend of C$0.01 per share on February 18, 2021. The dividend will be paid on March 26, 2021 to shareholders of record as of March 9, 2021 and is expected to total C$2,613.

Share-based compensation

Share-based compensation	12 Months Ended
Share-based compensation	Dec. 31, 2020
Disclosure of terms and conditions of share-based payment arrangement [abstract]
Share-based compensation [Text Block]	24. Share-based compensation (a) Cash-settled share-based compensation : Hudbay has three cash-settled share-based compensation plans, as described below. Deferred Share Units (DSU) At December 31, 2020, the carrying amount and the intrinsic value of the outstanding liability related to the DSU plan was $8,719 (December 31, 2019 - $3,876) (note 19). The following table outlines information related to DSUs granted, expenses recognized and payments made during the year. Year ended Dec. 31, 2020 Dec. 31, 2019 Granted during the year: Number of units 465,889 337,999 Weighted average price (C$/unit) $ 4.10 $ 5.89 Expenses recognized during the year 1 $ 5,149 $ 1,157 Payments made during the year (note 19) $ 497 $ 1,668 1 Restricted Share Units (RSU) RSUs At December 31, 2020, the carrying amount of the outstanding liability related to the RSU plan was $10,449 (December 31, 2019 - $5,477) (note 19). The following table outlines information related to RSUs granted, expenses recognized and payments made in the year. Year ended Dec. 31, 2020 Dec. 31, 2019 Number of units, beginning of year 1 2,223,999 3,666,867 Number of units granted during the year 1,388,786 1,080,741 Credits for dividends 17,587 7,554 Number of units forfeited during the year (44,678 ) (573,914 ) Number of units vested (645,357 ) (1,957,249 ) Number of units, end of year 1 2,940,337 2,223,999 Weighted average price - granted (C$/unit) $ 3.98 $ 8.98 Expenses recognized during the year 2 $ 6,750 $ 1,557 Payments made during the year (note 19) $ 2,646 $ 9,380 1 2 Performance Share Units (PSU) PSUs granted under the LTEP Plan may be settled in the form of Hudbay common shares or, at the option of the Company, the cash equivalent based on the market price of the common shares as of the vesting date. Hudbay has historically settled similar share-based compensation units in cash. The Company has determined that the appropriate accounting treatment is to classify the PSUs as cash settled transactions. At December 31, 2020, the carrying amount of the outstanding liability related to PSU plan was $2,030 (December 31, 2019 - $0) (note 19). The following table outlines information related to PSUs granted, expenses recognized and payments made in the year. Year ended Dec. 31, 2020 Dec. 31, 2019 Number of units, beginning of year — — Number of units granted during the year 1,089,569 — Credits for dividends 6,046 — Number of units, end of year 1,095,615 — Weighted average price - granted (C$/unit) $ 3.97 $ — Expenses recognized during the year (note 6c) $ 1,987 $ — Payments made during the year (note 19) $ — $ — (b) Equity-settled share-based compensation - stock options: The Company's stock option plan was approved in June 2005 and amended in May 2008 (the "Plan"). Under the amended Plan, the Company may grant to employees, officers, directors or consultants of the Company or its affiliates options to purchase up to a maximum of 13 million common shares of Hudbay. The Company has determined that the appropriate accounting treatment is to classify the stock options as equity settled transactions. During the year ended December 31, 2020, the Company granted 1,581,385 stock options (year ended December 31, 2019 - nil). The following table presents the weighted average fair value assumptions used in the Black-Scholes valuation of these options: For options granted during the year ended Dec. 31, 2020 Weighted average share price at grant date (CAD) $ 3.77 Risk-free rate 1.14% Expected dividend yield 0.5% Expected stock price volatility (based on historical volatility) 57.0% Expected life of option (months) 84 Weighted average per share fair value of stock options granted (CAD) $ 2.02 During the year ended December 31, 2020, 18,196 stock options were forfeited, which resulted in 1,563,189 options outstanding as of December 31, 2020. There are no stock options outstanding that are exercisable as at December 31, 2020. Dec. 31, 2020 Range of Number of Weighted Weighted Number of Weighted $3.76 - $3.92 1,563,189 6.16 $ 3.77 — $ — No options were granted under the Plan during the year ended December 31, 2019. Hudbay estimates expected life of options and expected volatility based on historical data, which may differ from actual outcomes. Year ended Year ended Dec. 31, 2020 Dec. 31, 2019 Number of shares subject to option Weighted- average exercise price C$ Number of shares subject to option Weighted average exercise price C$ Balance, beginning of year — — — $ — Number of units granted during the year 1,581,385 $ 3.77 — $ — Forfeited (18,196 ) $ 3.76 — $ — Balance, end of year 1,563,189 $ 3.77 — $ —

Earnings per share

Earnings per share	12 Months Ended
Earnings per share	Dec. 31, 2020
Basic earnings per share [abstract]
Earnings per share [Text Block]	25. Earnings per share Year ended Dec. 31, 2020 Dec. 31, 2019 Basic and diluted weighted average common shares outstanding 261,272,151 261,272,151 The determination of the diluted weighted-average number of common shares excludes the impact of 1,292,840 weighted-average stock options outstanding that were anti-dilutive for the year ended December 31, 2020 (December 31, 2019 - nil For periods where Hudbay records a loss, Hudbay calculates diluted loss per share using the basic weighted average number of shares. If the diluted weighted average number of shares were used, the result would be a reduction in the loss, which would be anti-dilutive. For the year ended December 31, 2020 and 2019, Hudbay calculated diluted loss per share using 261,272,151 common shares.

Capital management

Capital management	12 Months Ended
Capital management	Dec. 31, 2020
Statements [Line Items]
Capital management [Text Block]	26. Capital management The Company's definition of capital includes total equity and long-term debt. Hudbay's long-term debt balance as at December 31, 2020 was $1,135,675 (December 31, 2019 - $985,255). The Company's objectives when managing capital are to maintain a strong capital base in order to: — — Hudbay monitors its capital and capital structure on an ongoing basis to ensure they are sufficient to achieve the Company's short-term and long-term strategic objectives in a capital intensive industry. Hudbay faces several risks, including volatile metals prices, access to capital, and risk of delays and cost escalation associated with major capital projects. The Company continually assesses the adequacy of its capital structure to ensure its objectives are met. Hudbay monitors its cash and cash equivalents, which were $439,135 as at December 31, 2020 (2019 - $396,146), together with availability under its committed credit facilities. Hudbay invests its cash and cash equivalents primarily in Canadian bankers' acceptances, deposits at major Canadian and Peruvian banks, or treasury bills issued by the federal or provincial governments. In addition to the requirement to maintain sufficient cash balances to fund continuing operations, Hudbay must maintain sufficient cash to fund the interest expense on the long-term debt outstanding (note 17). As part of the Company's capital management activities, Hudbay monitors interest coverage ratios and leverage ratios.

Financial instruments

Financial instruments	12 Months Ended
Financial instruments	Dec. 31, 2020
Disclosure of detailed information about financial instruments [abstract]
Financial instruments [Text Block]	27. Financial instruments (a) Fair value and carrying value of financial instruments: The following presents the fair value ("FV") and carrying value ("CV") of Hudbay's financial instruments and non-financial derivatives: Dec. 31, 2020 Dec. 31, 2019 FV CV FV CV Financial assets at amortized cost Cash and cash equivalents 1 $ 439,135 $ 439,135 $ 396,146 $ 396,146 Restricted cash 1 337 337 337 337 Fair value through profit or loss Trade and other receivables 1, 2, 3 114,381 114,381 91,046 91,046 Non-hedge derivative assets 4 2,736 2,736 1,712 1,712 Investments 5 15,669 15,669 11,287 11,287 Total financial assets 572,258 572,258 500,528 500,528 Financial liabilities at amortized cost Trade and other payables 1, 2 209,413 209,413 184,604 184,604 Deferred Rosemont acquisition consideration 8 25,961 25,961 24,491 24,491 Other financial liabilities 6 41,912 40,787 21,338 24,000 Senior unsecured notes 7 1,277,124 1,139,695 1,050,126 991,558 Fair value through profit or loss Embedded derivatives 4 — — 9,074 9,074 Gold prepayment liability 9 137,031 137,031 — — Non-hedge derivative liabilities 4 15,312 15,312 10,295 10,295 Total financial liabilities 1,706,753 1,568,199 1,299,928 1,244,022 Net financial liability $ (1,134,495 ) $ (995,941 ) $ (799,400 ) $ (743,494 ) 1 2 3 4 5 6 7 8 9 Fair value hierarchy The table below provides an analysis by valuation method of financial instruments that are measured at fair value subsequent to recognition. Levels 1 to 3 are defined based on the degree to which fair value inputs are observable and have a significant effect on the recorded fair value, as follows: — — — December 31, 2020 Level 1 Level 2 Level 3 Total Financial assets measured at fair value Financial assets at FVTPL: Non-hedge derivatives $ — $ 2,736 $ — $ 2,736 Investments 15,669 — — 15,669 $ 15,669 $ 2,736 $ — $ 18,405 Financial liabilities measured at fair value Financial liabilities at FVTPL: Non-hedge derivatives $ — $ 15,312 $ — $ 15,312 Gold prepayment liability 1 — 137,031 — 137,031 Financial liabilities at amortized cost: Other financial liabilities — — 41,912 41,912 Senior unsecured notes 1,277,124 — — 1,277,124 $ 1,277,124 $ 152,343 $ 41,912 $ 1,471,379 1 December 31, 2019 Level 1 Level 2 Level 3 Total Financial assets measured at fair value Financial assets at FVTPL: Non-hedge derivatives $ — $ 1,712 $ — $ 1,712 Investments 11,287 — — 11,287 $ 11,287 $ 1,712 $ — $ 12,999 Financial liabilities measured at fair value Financial liabilities at FVTPL: Embedded derivatives $ — $ 9,074 $ — $ 9,074 Non-hedge derivatives — 10,295 — 10,295 Financial liabilities at amortized cost: Other financial liabilities — — 21,338 21,338 Senior unsecured notes 1,050,126 — — 1,050,126 $ 1,050,126 $ 19,369 $ 21,338 $ 1,090,833 The Company's policy is to recognize transfers into and transfers out of fair value hierarchy levels as of the date of the event or change in circumstances that caused the transfer. During the year ended December 31, 2020 and 2019 Hudbay did not make any such transfers. (b) Derivatives and hedging: Copper fixed for floating swaps Hudbay enters into copper fixed for floating swaps in order to manage the risk associated with provisional pricing terms in copper concentrate sales agreements. As at December 31, 2020, Hudbay had 43.4 million pounds of net copper swaps outstanding at an effective average price of $3.22/lb and settling across January to April 2021. As at December 31, 2019, Hudbay had 66.1 million pounds of net copper swaps outstanding at an effective average price of $2.67/lb and settling across January to April 2020. The aggregate fair value of the transactions at December 31, 2020 was a net liability of $13,198 (December 31, 2019 - a liability position of $8,362). Transactions involving derivatives are with large multi-national financial institutions that Hudbay believes to be credit worthy. Non-hedge derivative zinc contracts Hudbay enters into future dated fixed price sales contracts with zinc customers and, to ensure that the Company continues to receive a floating or unhedged realized zinc price, Hudbay enters into forward zinc purchase contracts that effectively offset the fixed price sales contracts. At December 31, 2020, Hudbay held contracts for forward zinc purchased of 3.5 million pounds (December 31, 2019 - 12.7 million pounds) that related to forward customer sales of zinc. Prices range from $0.87/lb to $1.30/lb (December 31, 2019 - $1.00/lb to $1.15/lb) and settlement dates extend to December 2021. The aggregate fair value of the transactions at December 31, 2020 was an asset position of $622 (December 31, 2019 - a net liability position of $221). (c) Provisionally priced receivables Changes in fair value of provisionally priced receivables Hudbay records changes in fair value of provisionally priced receivables related to provisional pricing in concentrate purchase, concentrate sale and certain other sale contracts. Under the terms of these contracts, prices are subject to final adjustment at the end of a future period after title transfers based on quoted market prices during the quotation period specified in the contract. The period between provisional pricing and final pricing is typically up to three months. Changes in fair value of provisionally priced receivables are presented in trade and other receivables when they relate to sales contracts and in trade and other payables when they relate to purchase contracts. At each reporting date, provisionally priced metals are marked-to-market based on the forward market price for the quotation period stipulated in the contract, with changes in fair value recognized in revenue for sales contracts and in inventory or cost of sales for purchase concentrate contracts. Cash flows related to changes in fair value of provisionally priced receivables are classified in operating activities. As at December 31, 2020 and 2019, Hudbay's net position consisted of contracts awaiting final pricing which are as indicated below: Metal in concentrate Sales awaiting final pricing Average YTD price ($/unit) Unit Dec. 31, 2020 Dec. 31, 2019 Dec. 31, 2020 Dec. 31, 2019 Copper pounds (in thousands) 47,901 72,977 3.52 2.80 Gold oz 18,106 16,152 1,894 1,522 Silver oz 123,380 124,371 26.35 17.86 The aggregate changes in fair value of provisionally priced receivables within the copper and zinc concentrate sales contracts at December 31, 2020, was an asset position of $21,295 (d) Embedded derivatives Prepayment option embedded derivative The senior unsecured note s (note 17) contain prepayment options, which represent embedded derivatives that require bifurcation from the host contract. The prepaym Pampacancha delivery obligation-embedded derivative During the first quarter of 2019, Hudbay recognized an obligation to deliver additional precious metal credits to Wheaton as a result of the Pampacancha deposit not being mined until a fter January 1, 2020 (note 15). The f (e) Other financial liabilities Gold prepayment liability The gold prepayment lia bility (note 15) requires settlement by physical delivery of gold ounces or equivalent gold credit (f) Financial risk management Hudbay's financial risk management activities are governed by Board-approved policies addressing risk identification, hedging authorization procedures and limits and reporting. The Company's policy objective, when hedging activities are undertaken, is to reduce the volatility of future profit and cash flow within the strategic and economic goals of Hudbay. From time to time, the Company employs derivative financial instruments, including forward and option contracts, to manage risk originating from exposures to commodity price risk, foreign exchange risk and interest rate risk. Significant derivative transactions are approved by the Board of Directors, and hedge accounting is applied when certain criteria have been met. Hudbay does not use derivative financial instruments for trading or speculation purposes. The following is a discussion of the Company's risk exposures. (i) Market risk Market risk is the risk that changes in market prices, including foreign exchange rates, commodity prices, share prices, and interest rates will cause fluctuations in the fair value or future cash flows of a financial instrument. Foreign currency risk Hudbay's primary exposure to foreign currency risk arises from: — — The Manitoba segment's primary financial instrument foreign currency exposure is on US denominated cash and cash equivalents, trade and other receivables and other financial liabilities. The Peru segment's primary financial instrument foreign currency exposure is on Peruvian soles cash and cash equivalents, trade and other payables and other financial liabilities. The Company's exposure to foreign currency risk was as follows based on notional financial instruments amounts stated in US equivalent dollars: Dec. 31, 2020 Dec. 31, 2019 CAD 1 USD 2 PEN 3 CAD 1 USD 2 PEN 3 Cash and cash equivalent $ 7,791 $ 3,895 $ 4,141 $ 8,394 $ 21,217 $ 7,617 Trade and other receivables 31 43,316 36,951 374 56,998 25,413 Other financial assets 15,669 — — 11,287 — — Trade and other payables (6,104 ) (1,419 ) (34,622 ) (5,719 ) (435 ) (22,618 ) Other financial liabilities — — (40,787 ) — — (24,000 ) $ 17,387 $ 45,792 $ (34,317 ) $ 14,336 $ 77,780 $ (13,588 ) 1 2 3 The following sensitivity analysis for foreign currency risk relates solely to financial instruments and non-financial derivatives that were outstanding as at the year-end date; each sensitivity calculation assumes all other variables are held constant. This analysis is based on values as at December 31, 2020 and does not reflect the overall effect that changes in market variables would have on the Company's operating results. December 31, 2020 Change of: Would have changed 2020 after-tax profit by: USD/CAD exchange rate 1 + 10% $ 1.1 million USD/CAD exchange rate 1 - 10% (1.4 ) million USD/PEN exchange rate 2 + 10% 2.0 million USD/PEN exchange rate 2 - 10% (2.5 ) million December 31, 2019 Change of: Would have changed 2019 after-tax profit by: USD/CAD exchange rate 1 + 10% $ 3.4 million USD/CAD exchange rate 1 - 10% (4.1 ) million USD/PEN exchange rate 2 + 10% 0.8 million USD/PEN exchange rate 2 - 10% (1.0 ) million 1 2 Commodity price risk Hudbay is exposed to market risk from prices for the commodities the Company produces and sells, such as copper, zinc, gold and silver. From time to time, Hudbay maintains price protection programs and conducts commodity price risk management through the use of derivative contracts. The following sensitivity analysis for commodity price risk relates solely to financial instruments and non-financial derivatives that were outstanding as at the year-end date; each sensitivity calculation assumes all other variables are held constant. This analysis is based on values as at December 31, 2020 and does not reflect the overall effect that changes in market variables would have on the Group's results of operations. December 31, 2020 Change of: Would have changed 2 020 after-tax profit by: Copper prices ($/lb) 3 + $0.30 $ (1.4) million Copper prices ($/lb) 3 — $0.30 1.4 million Zinc prices ($/lb) 4 + $0.10 0.3 million Zinc prices ($/lb) 4 — $0.10 (0.3) million December 31, 2019 Change of: Would have changed 2019 after-tax profit by: Copper prices ($/lb) 3 + $0.30 (2.0) million Copper prices ($/lb) 3 — $0.30 2.0 million Zinc prices ($/lb) 4 + $0.10 1.0 million Zinc prices ($/lb) 4 — $0.10 (1.0) million 3 4 Share price risk Hudbay is exposed to market risk from share prices of the Company's investments in listed Canadian metals and mining entities. These investments are made to foster strategic relationships, in connection with joint venture agreements and for investment purposes. Management monitors the value of these investments for the purposes of determining whether to add or reduce Hudbay's positions. The following sensitivity analysis of share price risk relates solely to financial instruments that were outstanding as at the year-end date; each sensitivity calculation assumes all other variables are held constant. This analysis is based on values as at December 31, 2020 and does not reflect the overall effect that changes in market variables would have on the Company's finance expenses. December 31, 2020 Change of: Would have changed 2020 after-tax profit by: Share prices + 25% $ 3.9 million Share prices — 25% (3.9) million December 31, 2019 Change of: Would have changed 2019 after-tax profit by: Share prices + 25% $ 2.8 million Share prices — 25% (2.8) million Interest rate risk Hudbay is exposed to the following interest rate risks: - - - The most material of these risks is the embedded derivative associated with its senior notes. This analysis is based on values at December 31, 2020 and does not reflect the overall effect that changes in market variables would have on the Company's finance expenses. December 31, 2020 Change of: Would have changed 2020 after-tax profit by: Interest rates + 2.00% $ (38.0) million Interest rates — 2.00% 48.5 million December 31, 2019 Change of: Would have changed 2019 after-tax profit by: Interest rates + 2.00% $ 2.3 million Interest rates — 2.00% (2.6) million (ii) Credit risk Credit risk is the risk of financial loss to Hudbay if a customer or counterparty to a financial instrument fails to meet its obligations. The Company's maximum exposure to credit risk at the reporting date is represented by the carrying amount, net of any impairment losses recognized, of financial assets and non-financial derivative assets recorded on the consolidated balance sheets. Refer to note 27a. A large portion of Hudbay's cash and cash equivalents are on deposits with major Schedule 1 Canadian banks. Deposits and other investments with Schedule 1 Canadian banks represented 90% of total cash and cash equivalents as at December 31, 2020 (2019 - 92%). Hudbay's investment policy requires it to comply with a list of approved investments, concentration and maturity limits, as well as credit quality. Credit concentrations in the Company's short term investments are monitored on an ongoing basis. Transactions involving derivatives are with counterparties Hudbay believes to be creditworthy. Management has a credit policy in place that requires the Company to obtain credit insurance from an investment grade credit insurance provider to mitigate exposure to credit risk in its receivables. At December 31, 2020, approximately 95% of Hudbay's trade receivables were insured or payable by letters of credit (2019 - 96% were insured or payable by letters of credit). Insured receivables have a credit insurance deductible of 10%. The deductible and any additional exposure to credit risk is monitored and approved on an ongoing basis. Two customers accounted for approximately 56% of total trade receivables as at December 31, 2020 (2019 - two customers accounted for approximately 63%). Credit risk for these customers is assessed as medium to low. As at December 31, 2020, none of the Company's trade receivables were aged more than 30 days (2019 - nil). (iii) Liquidity risk Liquidity risk is the risk that the Company will not be able to meet its obligations associated with financial liabilities. Hudbay's objective is to maintain sufficient liquid resources to meet operational and investing requirements. The following summarizes the contractual undiscounted cash flows of the Company's non-derivative and derivative financial liabilities, including any interest payments, by remaining contractual maturity and financial assets used to manage liquidity risk. The table includes all instruments held at the reporting date for which payments had been contractually agreed at the reporting date. The undiscounted amounts shown are gross amounts, unless the liabilities will be settled net. Amounts in foreign currency are translated at the closing rate at the reporting date. When a counterparty has a choice of when an amount is paid, the liability is allocated to the earliest possible time period. Dec. 31, 2020 Carrying amount Contractual cash flows 12 months or less 13 - 36 months 37 - 60 months More than 60 months Assets used to manage liquidity risk Cash and cash equivalents $ 439,135 $ 439,135 $ 439,135 — $ — $ — Restricted cash 337 337 337 — — — Trade and other receivables 114,381 114,381 114,381 — — — Non-hedge derivative assets 2,736 2,736 2,736 — — — $ 556,589 $ 556,589 $ 556,589 $ — $ — $ — Non-derivative financial liabilities Trade and other payables, including embedded derivatives $ (209,413 ) $ (209,413 ) $ (209,413 ) $ — $ — $ — Other financial 1 (40,787 ) (58,837 ) (12,097 ) (9,483 ) (6,578 ) (30,679 ) Deferred Rosemont acquisition consideration (25,961 ) (30,000 ) — (20,000 ) (10,000 ) — Long-term debt, including embedded derivatives (1,139,695 ) (1,726,904 ) (87,966 ) (168,188 ) (742,125 ) (728,625 ) Gold prepayment obligation (137,031 ) (137,031 ) — (137,031 ) — — $ (1,552,887 ) $ (2,162,185 ) $ (309,476 ) $ (334,702 ) $ (758,703 ) $ (759,304 ) Derivative financial liabilities Non hedge derivative contracts $ (15,312 ) $ (15,312 ) $ (15,312 ) $ — $ — $ — $ (15,312 ) $ (15,312 ) $ (15,312 ) $ — $ — $ — 1 Dec. 31, 2019 Carrying amount Contractual cash flows 12 months or less 13 - 36 months 37 - 60 months More than 60 months Assets used to manage liquidity risk Cash and cash equivalents $ 396,146 $ 396,146 $ 396,146 $ — $ — $ — Restricted cash 337 337 337 Trade and other receivables 91,046 91,046 89,451 — — 1,595 Non-hedge derivative assets 1,712 1,712 1,712 — — — $ 489,241 $ 489,241 $ 487,646 $ — $ — $ 1,595 Non-derivative financial liabilities Trade and other payables, including embedded derivatives $ (184,604 ) $ (184,604 ) $ (184,604 ) $ — $ — $ — Other financial 1 (24,000 ) (33,723 ) (6,672 ) (4,811 ) (4,734 ) (17,506 ) Deferred Rosemont acquisition consideration (24,491 ) (30,000 ) — (10,000 ) (20,000 ) — Long-term debt, including embedded derivatives (991,558 ) (1,350,540 ) (72,165 ) (149,500 ) (1,128,875 ) — $ (1,224,653 ) $ (1,598,867 ) $ (263,441 ) $ (164,311 ) $ (1,153,609 ) $ (17,506 ) Derivative financial liabilities Embedded derivative $ (9,074 ) $ (9,074 ) $ (9,074 ) $ — $ — $ — Non-hedge derivative contracts (10,295 ) (10,295 ) (10,295 ) — — — $ (19,369 ) $ (19,369 ) $ (19,369 ) $ — $ — $ — 1

Commitments and contingencies

Commitments and contingencies	12 Months Ended
Commitments and contingencies	Dec. 31, 2020
Notes to Financial Statements [Abstract]
Commitments and contingencies [Text Block]	28. Commitments and contingencies Capital commitments (a) Non capitalized lease commitments Hudbay has entered into various non-capitalized lease commitments for facilities and equipment. The leases expire in periods ranging from one to two years. There are no restrictions placed on the Company by entering into these leases. Future minimum lease payments under such cancellable leases recognized within results from operating activities at December 31 are: 2020 2019 Within one year $ 58,173 $ 57,860 After one year but not more than five years 2,192 26,395 More than five years — — $ 60,365 $ 84,255 (b) Capital Commitments As at December 31, 2020, Hudbay had outstanding capital commitments in Canada of approximately $22,539 of which $19,014 can be terminated, approximately $39,078 in Peru, all of which can be terminated, and approximately $179,656 in Arizona, primarily related to the Rosemont project, of which approximately $89,312 can be terminated by Hudbay. (c) Contingent liabilities Contingent liabilities Hudbay is involved in various claims, litigation and other matters arising in the ordinary course and conduct of business. While it is not possible to determine the ultimate outcome of such actions at this time, and inherent uncertainties exist in predicting such outcomes, it is the Company's belief that the ultimate resolution of such actions is not reasonably likely to have mat As part of the streaming agreement with Wheaton for the 777 mine, Hudbay must repay, with precious metal credits, the legal deposit provided by Wheaton by August 1, 2052, the expiry date of the arrangement. If the legal deposit is not fully repaid with precious metal credits related to 777 production by the expiry date, a cash payment for the remaining amount will be due at the expiry date of the agreement. As a result of changes in the remaining 777 mine reserves and lower precious metal prices, there is a possibility that an amount of Wheaton's legal deposit may not be repaid by means of 777 mine's production over its expected remaining mine life.

Related parties

Related parties	12 Months Ended
Related parties	Dec. 31, 2020
Disclosure of transactions between related parties [abstract]
Related parties [Text Block]	29. Related parties (a) Group companies The financial statements include the financial statements of the Company and the following significant subsidiaries: Beneficial ownership of ultimate controlling party (Hudbay Minerals Inc.) Name Jurisdiction Business Entity's Parent 2020 2019 HudBay Marketing & Sales Inc. Canada Marketing and sales HMI 100% 100% HudBay Peru Inc. British Columbia Holding company HMI 100% 100% HudBay Peru S.A.C. Peru Exploration/development Peru Inc. 100% 100% HudBay (BVI) Inc. British Virgin Islands Precious metals sales Peru Inc. 100% 100% Hudbay Arizona Inc. British Columbia Holding company HMI 100% 100% Rosemont Copper Company Arizona Exploration/development HudBay Arizona (US) Holding Corporation 100% 100% Transactions between the Company and its subsidiaries, which are related parties of the Company, have been eliminated on consolidation and are not disclosed in this note. ( b) Compensation of key management personnel The Company's key management includes members of the Board of Directors, Hudbay's Chief Executive Officer, Hudbay's senior vice presidents and vice presidents. Total compensation to key management personnel was as follows: 2020 2019 Short-term employee benefits 1 $ 7,951 $ 8,319 Post-employment benefits 639 762 Long-term share-based awards 6,381 6,966 $ 14,971 $ 16,047 1

Supplementary cash flow informa

Supplementary cash flow information	12 Months Ended
Supplementary cash flow information	Dec. 31, 2020
Supplementary Cash Flow Information [Abstract]
Supplementary cash flow information [Text Block]	30. Supplementary cash flow information (a) Change in non-cash working capital: Year ended 2020 2019 Change in: Trade and other receivables $ (37,720 ) $ 3,252 Other financial assets/liabilities 4,077 12,540 Inventories (2,867 ) (11,759 ) Prepaid expenses (3,722 ) (3,484 ) Trade and other payables 36,247 5,613 Provisions and other liabilities 1,602 (2,590 ) $ (2,383 ) $ 3,572 (b) Non-cash transactions: During the year ended December 31, 2020 and 2019, Hudbay entered into the following non-cash investing and financing activities which are not reflected in the consolidated statements of cash flows: - - - note 6d)

Segmented information

Segmented information	12 Months Ended
Segmented information	Dec. 31, 2020
Disclosure of operating segments [abstract]
Segmented information [Text Block]	31. Segmented information Hudbay is an integrated metals producer. When making decisions on expansions, opening or closing mines, as well as day to day operations, management evaluates the profitability of the overall operation of the Company. Hudbay's main mining operations are located in Manitoba and Saskatchewan (Canada) and Cusco (Peru) and are included in the Manitoba segment and Peru segment, respectively. The Manitoba and Peru segments generate Hudbay's revenue. The Manitoba segment sells copper concentrate (containing copper, gold and silver), zinc metal and other products. The Peru segment consists of Hudbay's Constancia operation and sells copper concentrate and molybdenum concentrate. Hudbay's Arizona segment consists of the Rosemont project located in Arizona. Corporate and other activities include the Company's exploration activities in Chile, and Nevada. The exploration entities are not individually significant, as they do not meet the minimum quantitative thresholds. Corporate activities are not considered a segment and are included as a reconciliation to total consolidated results. Accounting policies for each reported segment are the same as those of the Company. Results from operating activities represents the profit earned by each segment without allocation of corporate costs. This is the measure reported to the chief operating decision-maker, Hudbay's President and Chief Executive Officer, for the purposes of resource allocation and the assessment of segment performance. Total assets and liabilities do not reflect intercompany balances, which have been eliminated on consolidation. Year ended December 31, 2020 Manitoba Peru Arizona Corporate and other activities Total Revenue from external customers $ 615,699 $ 476,719 $ — $ — $ 1,092,418 Cost of sales Mine operating costs 391,504 300,087 — — 691,591 Depreciation and amortization 177,552 184,275 — — 361,827 Gross profit (loss) 46,643 (7,643 ) — — 39,000 Selling and administrative expenses — — — 41,408 41,408 Exploration and evaluation expenses 6,491 6,295 3,870 540 17,196 Other expenses 8,382 4,901 2,066 2,234 17,583 Results from operating activities $ 31,770 $ (18,839 ) $ (5,936 ) $ (44,182 ) $ (37,187 ) Net interest expense on long term debt 82,712 Accretion on streaming arrangements 56,670 Change in fair value of financial instruments (29,370 ) Other net finance costs 31,890 Loss before tax (179,089 ) Tax recovery (34,505 ) Loss for the year $ (144,584 ) Year ended December 31, 2019 Manitoba Peru Arizona Corporate and other activities Total Revenue from external customers $ 537,421 $ 700,018 $ — $ — $ 1,237,439 Cost of sales Mine operating costs 385,159 356,183 — — 741,342 Depreciation and amortization 135,429 209,126 — — 344,555 Gross profit 16,833 134,709 — — 151,542 Selling and administrative expenses — — — 36,170 36,170 Exploration and evaluation expenses 18,476 5,804 — 6,494 30,774 Other expenses 8,201 14,022 28,149 744 51,116 Impairment loss — — 322,249 — 322,249 Results from operating activities $ (9,844 ) $ 114,883 $ (350,398 ) $ (43,408 ) $ (288,767 ) Net interest expense on long term debt 68,375 Accretion on streaming arrangements 69,772 Change in fair value of financial instruments 8,247 Other net finance costs 17,602 Loss before tax (452,763 ) Tax recovery (108,953 ) Loss for the year $ (343,810 ) December 31, 2020 Manitoba Peru Arizona Corporate and other activities Total Total assets $ 801,691 $ 2,535,939 $ 718,982 $ 610,033 $ 4,666,645 Total liabilities 562,013 973,756 76,926 1,354,144 2,966,839 Property, plant and equipment 1 699,884 2,290,097 709,939 31,735 3,731,655 1 December 31, 2020 Manitoba Peru Arizona Corporate and other activities Total Additions to property, plant and equipment $ 159,313 $ 208,805 $ 18,640 $ 32 $ 386,790 December 31, 2019 Manitoba Peru Arizona Corporate and other activities Total Total assets $ 779,896 $ 2,556,895 $ 700,799 $ 423,467 $ 4,461,057 Total liabilities 556,267 926,642 78,988 1,051,037 2,612,934 Property, plant and equipment 1 684,679 2,253,404 691,538 32,938 3,662,559 1 December 31, 2019 Manitoba Peru Arizona Corporate and other activities Total Additions to property, plant and equipment $ 143,418 $ 101,717 $ 38,923 $ 905 $ 284,963 Geographical Segments The following tables represent revenue information regarding the Group's geographical segments for the years ended December 31: 2020 2019 Revenue by customer location 1 Canada $ 422,403 $ 418,636 China 215,278 158,795 United States 206,906 209,382 Philippines 77,575 71,506 Peru 56,437 110,411 Switzerland 55,703 162,167 Singapore 29,314 71,506 Germany 11,725 10,731 Other 17,077 24,305 $ 1,092,418 $ 1,237,439 1 During the year ended December 31, 2020, eight customers accounted for approximately 36%, 17%, 13%, 7%, 7%, 5%, 5%, and 5% respectively, of total revenue during the year. Revenue from these customers has been presented in the Manitoba and Peru operating segments. During the year ended December 31, 2019, six customers accounted for approximately 24%, 9%, 9%, 8%, 5% and 5%, respectively, of total revenue during the year. Revenue from these customers has been presented in the Manitoba and Peru operating segments.

Events after the reporting peri

Events after the reporting period	12 Months Ended
Events after the reporting period	Dec. 31, 2020
Disclosure of non-adjusting events after reporting period [abstract]
Events after the reporting period [Text Block]	32. Events after the reporting period As a result of the delay in finalizing the remaining land user agreements coupled with new, heightened, domestic travel restrictions announced on January 26, 2021 by the government of Peru, Hudbay has concluded that it no longer expects to mine four million tonnes of ore from the Pampacancha deposit by June 30, 2021. If we fail to meet this milestone, we will be required to deliver an additional 8,020 ounces of gold to Wheaton in equal quarterly installments, at prevailing market prices, starting September 30, 2021.

Significant accounting polici_2

Significant accounting policies (Policies)	12 Months Ended
Significant accounting policies (Policies)	Dec. 31, 2020
Significant Accounting Policies [Abstract]
Basis of consolidation [Policy Text Block]	a) Basis of consolidation: Intercompany balances and transactions are eliminated upon consolidation. When a Hudbay entity transacts with an associate or jointly controlled entity of the Company, unrealized profits and losses are eliminated to the extent of Hudbay's interest in the relevant associate or joint venture. The accounting policies of Hudbay's entities are changed when necessary to align them with the policies adopted by the Company. Subsidiaries A subsidiary is an entity controlled by Hudbay. The financial statements of subsidiaries are included in the consolidated financial statements from the date that control commences until the date that control ceases. Business combinations and goodwill When Hudbay makes an acquisition, it first determines whether the assets acquired and liabilities assumed constitute a business, in which case the acquisition requires accounting as a business combination. Management applies judgement in determining whether the acquiree is capable of being conducted and managed for the purpose of providing a return, considering the inputs of the acquiree and processes applied to those inputs that have the ability to create outputs. Hudbay applies the acquisition method of accounting to business combinations, whereby the goodwill is measured at the acquisition date as the fair value of the consideration transferred including the recognized amount of any non-controlling interests in the acquiree. When the excess is negative, a bargain purchase gain is recognized immediately in the consolidated income statements. The assessment of fair values on acquisition includes those mineral reserves and resources that are able to be reliably measured. In determining these fair values, management must also apply judgement in areas including future cash flows, metal prices, exchange rates and appropriate discount rates. Changes in such estimates and assumptions could result in significant differences in the amount of goodwill recognized. The consideration transferred is the aggregate of the fair values, at the date of the acquisition, of the sum of the assets transferred, the liabilities incurred or assumed, and the equity instruments issued by the acquirer in exchange for control of the acquiree. Acquisition-related costs are recognized in the consolidated income statements as incurred, unless they relate to issuance of debt or equity securities. Where applicable, the consideration transferred includes any asset or liability resulting from a contingent consideration arrangement and measured at its acquisition date fair value. Subsequent changes in such fair values are adjusted against the cost of acquisition where they qualify as measurement period adjustments. All other subsequent changes in the fair value of contingent consideration classified as an asset or liability are accounted for in accordance with relevant IFRS. Changes in the fair value of contingent consideration classified as equity are not recognized. Where a business combination is achieved in stages, the Company's previously held interests in the acquired entity are remeasured to fair value at the acquisition date, which is the date Hudbay attains control, and any resulting gain or loss is recognized in the consolidated income statements. Amounts previously recognized in other comprehensive income ("OCI") related to interests in the acquiree prior to the acquisition date are reclassified to the consolidated income statements, where such treatment would be appropriate if that interest were disposed of. After initial recognition, goodwill is measured at cost less any accumulated impairment losses. For the purpose of impairment testing, goodwill acquired in a business combination is, from the acquisition date, allocated to each of Hudbay's CGUs that are expected to benefit from the synergies of the combination, irrespective of whether other assets or liabilities of the acquiree are assigned to those units. Goodwill is allocated to the lowest level at which it is monitored for internal management purposes and is not larger than an operating segment before aggregation. Where goodwill forms part of a CGU and part of the operation within that unit is disposed of, the goodwill associated with the disposed operation is included in the determination of any gain or loss on disposal. Goodwill is not amortized and is tested for impairment annually and whenever there is an indication of impairment. If any such indication exists, the recoverable amount of the CGU is estimated in order to determine the extent of the impairment, if any. The recoverable amount is determined as the higher of fair value less direct costs to sell and the CGU's value in use. An impairment loss in respect of goodwill is not reversed. Fair value for mineral interests and related goodwill is generally determined as the present value of the estimated future cash flows expected to arise from the continued use of the asset, including any expansion prospects, and its eventual disposal, using assumptions that an independent market participant may take into account. Value in use is determined as the present value of the estimated future cash flows expected to arise from the continued use of the asset in its present form and its eventual disposal. Value in use is determined by applying assumptions specific to Hudbay's continued use and cannot take into account future development. The weighted average cost of capital of Hudbay or comparable market participants is used as a starting point for determining the discount rates, with appropriate adjustments for the risk profile of the countries in which the individual CGUs operate and the specific risks related to the development of the project. Where the asset does not generate cash flows that are independent of other assets, Hudbay estimates the recoverable amount of the CGU to which the asset belongs. If the carrying amount of an asset or CGU exceeds its recoverable amount, the carrying amount of the asset or CGU is reduced to its recoverable amount. An impairment loss is recognized as an expense in the consolidated income statements.
Translation of foreign currencies [Policy Text Block]	b) Translation of foreign currencies: Management determines the functional currency of each Hudbay entity as the currency of the primary economic environment in which the entity operates. Foreign currency transactions Transactions in foreign currencies are translated to the respective functional currencies of Hudbay's entities at exchange rates in effect at the transaction dates. At the end of each reporting period, monetary assets and liabilities denominated in foreign currencies are translated to the functional currency using the closing exchange rate. Non-monetary assets and liabilities measured at fair value are translated using the exchange rates at the date when fair value was determined. Non-monetary assets and liabilities measured at historical cost in a foreign currency are translated using exchange rates that were in effect at the transaction dates. The same translations are applied when an entity prepares its financial statements from books and records maintained in a currency other than its functional currency, except revenue and expenses may be translated at monthly average exchange rates that approximate those in effect at the transaction dates. Foreign currency gains and losses arising on period-end revaluations are recognized in the consolidated income statements, except for a financial liability designated as a hedge of a net investment in a foreign operation, or qualifying cash flow hedges, which are recognized in OCI. Foreign operations For the purpose of the consolidated financial statements, assets and liabilities of Hudbay's entities that have functional currencies other than the US dollar are translated to US dollars at the reporting date using the closing exchange rate. Revenue and expenses are translated at monthly average exchange rates that approximate those in effect at the transaction dates. Differences arising from these foreign currency translations are recognized in OCI and presented within equity in the foreign currency translation reserve. When a foreign operation is disposed, the relevant exchange differences accumulated in the foreign currency translation reserve are transferred to the consolidated income statements as part of the profit or loss on disposal. On the partial disposal of a subsidiary that includes a foreign operation, the relevant proportion of such amount is reattributed to non-controlling interests. On disposal of a partial investment in an associate or joint venture that includes a foreign operation while retaining significant influence or joint control, the relevant proportion is reclassified to profit or loss. Net investment in a foreign operation Foreign currency gains and losses arising on translation of a monetary item receivable from or payable to a foreign operation for which settlement is neither planned nor likely to occur in the foreseeable future are considered to form part of a net investment in the foreign operation. Such gains and losses are recognized in OCI and presented within equity in the foreign currency translation reserve.
Revenue recognition [Policy Text Block]	c) Revenue from the sale of goods is measured at the fair value of the consideration received or receivable, net of treatment and refining charges and pre-production revenue. Revenue from the sale of by-products is included within revenue. Revenue is recognized when control of the goods sold has been transferred to the buyer. Control is deemed to have passed to the customer when significant risk and reward of the product has passed to the buyer, Hudbay has a present right to payment and physical possession of the product has been transferred to the buyer. Sale of concentrate and finished zinc frequently occur under the following terms, and management has assessed these terms in order to determine timing of transfer of control. Incoterms used by Hudbay Revenue recognized when goods: Cost, Insurance and Freight (CIF) Are loaded on board the vessel Free on Board (FOB) Are loaded on board the vessel Delivered at place (DAP) Arrive at the named place of destination Delivered at terminal (DAT) Arrive at the named place of destination Free Carrier (FCA) Arrive at the named place of delivery Sales of concentrate and certain other products are provisionally priced. For these contracts, sales prices are subject to final adjustment at the end of a future period after shipment, based on quoted market prices during the quotational period specified in the contract. Revenue is recognized when the above criteria are achieved, using weight and assay results and forward market prices to estimate the fair value of the total consideration receivable. Therefore, revenue is initially recorded based on an initial provisional invoice. Subsequently, at each reporting date, until the provisionally priced sale is finalized, sales receivables are marked to market, with adjustments (both gains and losses) recorded within revenue separately as "Pricing and volume adjustments" in the notes to the consolidated financial statements and in trade and other receivables on the consolidated balance sheets. As per IFRS 15 Revenue, variability in price is deemed to be fair value movements on provisionally priced receivables under the scope of IFRS 9 Financial Instruments; variability in quantities is deemed to be variable consideration. The variable consideration from weights and assay changes to quantities has been assessed to be insignificant to warrant precluding revenue being recorded as a result of possible future sales reversals. An annual analysis of the accuracy of our weights and assays is completed, and if the accuracy rate falls below a certain threshold, management then evaluates whether revenue from future sales should be constrained as a result of it being highly probable that there would be a significant revenue reversal in the future. Hudbay only includes in the transaction price an amount which is not highly likely to be subject to significant subsequent revenue reversal. Within sales contracts with customers, separate performance obligations may arise pertaining to the shipping of goods sold. If applicable, costs and the transaction price are allocated on a relative standalone selling basis to any separate performance obligations and are recognized over the period of time the goods sold are shipped, on a gross basis. Hudbay recognizes deferred revenue in the event it receives payments from customers before a sale meets criteria for revenue recognition. There is a significant financing component associated with the Company's precious metal streaming arrangements since funds were received in advance of the delivery of concentrate. When a significant financing component is recognized, finance expense will be higher and revenues will be higher as the larger deferred revenue balance is amortized to revenues. A market-based discount rate is utilized at the inception of each of the respective stream agreements to determine a discount rate for computing the interest charges for the significant financing component of the deferred revenue balance. As product is delivered, the deferred revenue amount including accreted interest will be drawn down. The draw down rate requires the use of proven and probable reserves and certain resources in the calculation that are beyond proven and probable reserves which management is reasonably confident will be transferable to reserves. Key estimates used in determining the significant financing component include the discount rate and the reserve and resources assumed for conversion.
Cost of sales [Policy Text Block]	d) Cost of sales: Cost of sales consists of those costs previously included in the measurement of inventory sold during the period, as well as certain costs not included in the measurement of inventory, such as the cost of warehousing and distribution to customers, provisional pricing adjustments related to purchased concentrates, profit sharing, royalty payments, share-based compensation expense and other indirect expenses related to producing operations.
Cash and cash equivalents [Policy Text Block]	e) Cash and cash equivalents include cash, demand deposits and short-term, highly liquid investments that are readily convertible to known amounts of cash and are subject to an insignificant risk of changes in value. Cash equivalents have maturities of three months or less at the date of acquisition. Interest earned is included in finance income on the consolidated income statements and in investing activities on the consolidated statements of cash flows. Amounts that are restricted from being used for at least twelve months after the reporting date are classified as non-current assets and presented in restricted cash on the consolidated balance sheets. Changes in restricted cash balances are classified as investing activities on the consolidated statements of cash flows.
Inventories [Policy Text Block]	f) Inventories consist of stockpiles, in-process inventory (concentrates and metals), metal products and supplies. Concentrates, metals and all other saleable products are valued at the lower of cost and estimated net realizable value. Net realizable value represents the estimated selling price for inventories less all estimated costs of completion and costs necessary to make the sale. Where the net realizable value is less than cost, the difference is charged to the consolidated income statements as an impairment charge in cost of sales. Costs associated with stripping activities in an open pit mine are capitalized to inventory and recorded through cost of sales unless the stripping activity can be shown to improve access to further quantities of ore that will be mined in future periods, in which case, the stripping costs are capitalized to property, plant and equipment. Cost of production of concentrate inventory is determined on a weighted average cost basis and the cost of production of finished metal inventory is determined using the first in first out basis. The cost of production includes direct costs associated with conversion of production inventory based on normal production capacity: material, labour, contractor expenses, purchased concentrates, and an attributable portion of production overheads and depreciation of all property, plant and equipment involved with the mining and production process. Hudbay measures in-process inventories based on assays of material received at metallurgical plants and estimates of recoveries in the production processes. Due to significant uncertainty associated with volume and metal content, immaterial costs are not allocated to routine operating levels of stockpiled ore. Estimates and judgements are required to assess the nature of any significant changes to levels of ore stockpiles and determining whether allocation of costs is required. Supplies are valued at the lower of average cost and net realizable value.
Intangible assets [Policy Text Block]	g) Computer software is measured at cost less accumulated amortization and accumulated impairment losses. Costs include all directly attributable costs necessary to create, produce and prepare the asset to be capable of operating it in the manner intended by management. Amortization methods, useful lives, and residual values if any, are reviewed at each year end and adjusted prospectively, if required. When an intangible asset is disposed of, or when no further economic benefits are expected, the asset is derecognized, and any resulting gain or loss is recorded in the consolidated income statements. Currently, the Company's intangible assets relate primarily to enterprise resource planning ("ERP") information systems, which are amortized over their estimated useful lives.
Exploration and evaluation expenditures [Policy Text Block]	h) Exploration and evaluation expenditures: Exploration and evaluation activity begins when Hudbay obtains legal rights to explore a specific area and involves the search for mineral reserves, the determination of technical feasibility, and the assessment of commercial viability of an identified resource. Expenditures incurred in the exploration and evaluation phase include the cost of acquiring interests in mineral rights, licenses and properties and the costs of Hudbay's exploration activities, such as researching and analyzing existing exploration data, gathering data through geological studies, exploratory drilling, trenching, sampling, and certain feasibility studies. Hudbay expenses the cost of its exploration and evaluation activities and capitalizes the cost of acquiring interests in mineral rights, licenses and properties in business combinations, asset acquisitions or option agreements. Amounts capitalized are recognized as exploration and evaluation assets and presented in property, plant and equipment. Exploration and evaluation assets acquired as a result of an asset acquisition or option agreement are initially recognized at cost, and those acquired in a business combination are recognized at fair value on the acquisition date. They are subsequently carried at cost less accumulated impairment. No depreciation is charged during the exploration and evaluation phase. Hudbay expenses the cost of subsequent exploration and evaluation activity related to acquired exploration and evaluation assets. Cash flows associated with acquiring exploration and evaluation assets are classified as investing activities in the consolidated statements of cash flows; those associated with exploration and evaluation expenses are classified as operating activities. Judgement is required in determining whether the respective costs are eligible for capitalization where applicable, and whether they are likely to be recoverable, which may be based on assumptions about future events and circumstances. Estimates and assumptions made may change if new information becomes available. Hudbay monitors exploration and evaluation assets for factors that may indicate their carrying amounts are not recoverable. If such indicators are identified, the Company tests the exploration and evaluation assets or their CGUs, as applicable, for impairment. Hudbay also tests for impairment when assets reach the end of the exploration and evaluation phase. Exploration and evaluation assets are transferred to capital works in progress within property, plant and equipment once the Company determines that probable future economic benefits will be generated as a result of the expenditures. Hudbay's determination of probable future economic benefit is based on management's evaluation of the technical feasibility and commercial viability of the geological properties of a given ore body based on information obtained through evaluation activities, including metallurgical testing, resource and reserve estimates and the economic assessment of whether the ore body can be mined economically. Tools that may be used to determine this include a preliminary feasibility study, confidence in converting resources into reserves and the probability that the property could be developed into a mine site. At that time, the property is considered to enter the development phase, and subsequent evaluation costs are capitalized.
Property, plant and equipment [Policy Text Block]	(i) Hudbay measures items of property, plant and equipment at cost less accumulated depreciation and any accumulated impairment losses. The initial cost of an item of property, plant and equipment includes its purchase price or construction costs, including import duties and non-refundable purchase taxes, any costs directly attributable to bringing the asset into operation, and for qualifying assets, borrowing costs. The initial cost of property, plant and equipment also includes the initial estimate of the cost of dismantling and removing the item and restoring the site on which it is located, the obligation which Hudbay incurs either when the item is acquired or as a consequence of having used the item during a particular period for purposes other than to produce inventories during that period. Capitalization of costs ceases once an asset is in the location and condition necessary for it to be capable of operating in the manner intended by management. At this time, depreciation commences. For a new mine, this occurs upon commencement of commercial production. Up to and including December 31, 2020, any revenue earned in the process of preparing an asset to be capable of operating in the manner intended by management is included in the cost of the constructed asset. Any other incidental revenue earned prior to commencement of commercial production is recognized in the consolidated income statements. Carrying amounts of property, plant and equipment, including right-of-use ("ROU") assets, are depreciated to their estimated residual value over the estimated useful lives of the assets or the estimated life of the related mine or plant, if shorter. Where components of an asset have different useful lives, depreciation is calculated on each separate component. Components may be physical or non-physical, including the cost of regular major inspections and overhauls required in order to continue operating an item of property, plant and equipment. Certain items of property, plant and equipment are depreciated on a unit-of-production basis. The unit-of-production method is based on proven and probable tonnes of ore reserves. There are numerous uncertainties inherent in estimating ore reserves, and assumptions that were valid at the reporting date may change when new information becomes available. The actual volume of ore extracted and any changes in these assumptions could affect prospective depreciation rates and carrying values. The carrying amount of an item of property, plant and equipment is derecognized on disposal or when no future economic benefits are expected from its use or disposal. Upon derecognition of an item of property, plant and equipment, the difference between its carrying value and net sales proceeds, if any, is presented as a gain or loss in other operating income or expense in the consolidated income statements. i. Capital works in progress: Capital works in progress consist of items of property, plant and equipment in the course of construction or mineral properties in the course of development, including those transferred upon completion of the exploration and evaluation phase. On completion of construction or development, costs are transferred to plant and equipment and/or mining properties as appropriate. Capital works in progress are not depreciated. ii. Mining properties: Mining properties consist of costs transferred from capital works in progress when a mining property reaches commercial production, costs of subsequent mine and exploration development, and acquired mining properties in the production stage. Mining properties include costs directly attributable to bringing a mineral asset into the state where it is capable of operating in the manner intended by management and includes such costs as the cost of shafts, ramps, track haulage drifts, ancillary drifts, pumps, electrical substations, refuge stations, ventilation raises, permanent manways, and ore and waste pass raises. The determination of development costs to be capitalized during the production stage of a mine operation requires the use of judgements and estimates such as estimates of tonnes of waste to be removed over the life of the mining area and economically recoverable reserves extracted as a result. A mining property is considered to be capable of operating in a manner intended by management when it commences commercial production based on pre-established criteria. Upon commencement of commercial production, a mining property is depreciated on a unit-of-production method. Unit-of-production depreciation rates are determined based on the related proven and probable mineral reserves and associated future development costs. Subsequent mine development costs are capitalized to the extent they are incurred in order to access reserves mineable over more than one year. Ongoing maintenance and development expenditures are expensed as incurred and included in cost of sales in profit or loss. These include ore stope access drifts, footwall and hangingwall drifts in stopes, drawpoints, drill drifts, sublevels, slots, drill raises, stope manway access raises and definition diamond drilling. iii. Plant and equipment: Plant and equipment consists of buildings and fixtures, surface and underground fixed and mobile equipment and assets under lease. Plant and equipment are depreciated on either unit-of-production or straight-line basis based on factors including the production life of assets and mineable reserves. In general, mining assets are depreciated using a unit-of-production method; equipment is depreciated using the straight-line method, based on the shorter of its useful life and that of the related mine or facility; and plants are depreciated using the straight-line method, with useful lives limited by those of related mining assets. iv. Right-of-use lease assets: At inception of a contract, Hudbay assesses whether a contract is, or contains, a lease. A contract is, or contains, a lease if the contract conveys the right to control the use of an identified asset for a period of time in exchange for consideration. The Company assesses the following criteria in the determination of whether a contract conveys the right to control the use of an identified asset: • The contract involves the use of an identified asset - this may be specified explicitly or implicitly, and should be physically distinct or represent substantially all of the capacity of a physically distinct asset. If the supplier has substantive substitution rights, then the asset is not identified; • Hudbay has the right to obtain substantially all of the economic benefits from use of the asset throughout the period of use; and • Hudbay has the right to direct the use of the asset by means of decision making rights that are most relevant to changing how and for what purpose the asset is used. In the case where decisions about the asset's purpose is predetermined, Hudbay is deemed to have the right to direct the use of the asset if either: • Hudbay has the right to operate the asset; or, • Hudbay designed the asset in a way that predetermines how and for what purpose it will be used. The Company recognizes a ROU asset and lease liability at the lease commencement date. The initial measurement of the ROU asset is on a present value basis. This is based on the calculated lease liability plus any initial direct costs incurred, an estimate of removal or restoration costs, and any payments made prior to commencement of the lease less any lease incentives received. The right of use asset is subsequently depreciated using the straight-line method from the commencement date to the earlier of the end of the useful life of the right-of-use asset or the end of the lease term. The estimated useful lives of the right-of-use assets are determined on the same basis as those of property and equipment. In addition, the right-of-use asset is periodically reduced by impairment losses, if any, and adjusted for certain remeasurements of the lease liability. The lease liability is measured at the present value of the lease payments that are yet to be paid at the commencement date, discounted using the interest rate implicit in the lease or, if that rate cannot be easily determined, Hudbay's incremental borrowing rate. Generally, the Company uses its incremental borrowing rate as the discount rate for applicable leases. Lease payments included in the measurement of the lease liability comprise fixed payments including in substance fixed payments and variable payments that depend on an index or rate, amounts expected to be payable under a residual value guarantee and the additional costs Hudbay reasonably expects to incur due to purchase options, extension options and termination options reasonably expected to be exercised. The lease liability is measured at amortized cost using the effective interest method. It is remeasured when there is a change in the expected future cash flows of a leasing contract either due to a change in index or rate, or due to a change in terms of the contract. When the lease liability is remeasured in this way, a corresponding adjustment is made to the carrying amount of the right-of-use asset, or is recorded in profit or loss if the carrying amount of the right-of-use asset is zero. Hudbay has elected not to separate non-lease components and account for the lease and non-lease components as a single lease component for lease contracts of all asset classes. The Company has elected not to recognize ROU assets and lease liabilities for short-term leases of machinery that have a lease term of 12 months or less and leases of low-value assets. Hudbay recognizes the lease payments associated with these leases as an expense on a straight-line basis over the lease term. Hudbay does not enter into transactions where the Company acts as a lessor. The incremental borrowing rate used for new ROU leases is a key management judgement. v. Depreciation rates of major categories of assets: • Capital works in progress - not depreciated • Mining properties - unit-of- production • Mining asset - unit-of- production • Plant and Equipment ◦ Equipment - straight-line over 1 to 20 years ◦ Other plant assets - straight-line over 1 to 20 years/unit-of-production • ROU Assets - straight -line over 1 to 20 years Hudbay reviews its depreciation methods, remaining useful lives and residual values at least annually and accounts for changes in estimates prospectively. vi. Commercial production: Commercial production is the level of activities intended by management for a mine, or a mine and mill complex, to be capable of operating in the manner intended by management. Hudbay considers a range of factors when determining the level of activity that represents commercial production for a particular project, including a predetermined percentage of design capacity for the mine and mill; achievement of continuous production, ramp-ups, or other output; or specific factors such as recoveries, grades, or inventory build-ups. In a phased mining approach, management may consider achievement of specific milestones at each phase of completion. In a non-phased mining approach, management considers average actual metrics that are at least 60% of average design capacity or plan over a continuous period. Management assesses the operation's ability to sustain production over a period of approximately one to three months, depending on the complexity related to the stability of continuous operation. Commercial production is considered to have commenced, and depreciation expense is recognized, at the beginning of the month after criteria have been met. vii. Capitalized borrowing costs: The Company capitalizes borrowing costs that are directly attributable to the acquisition, construction or production of qualifying assets, which are assets that necessarily take a substantial period of time, generally one year or more, to get ready for their intended use or sale. Capitalization of borrowing costs ceases once the qualifying assets commence commercial production or are otherwise ready for their intended use or sale. Where funds are borrowed specifically to finance a project, the amount capitalized represents the actual borrowing costs incurred. Where the funds used to finance a project form part of general borrowings, the amount capitalized is calculated using a weighted average of interest rates applicable to relevant general borrowings of Hudbay during the period, to a maximum of actual borrowing costs incurred. Investment income earned by temporarily investing specific borrowings pending their expenditure on qualifying assets is deducted from the borrowing costs eligible for capitalization. Capitalization of interest is suspended during extended periods in which active development is interrupted. All other borrowing costs are recognized in the consolidated income statements in the period in which they are incurred. viii. Capitalized stripping costs: Costs associated with stripping activities in an open pit mine are capitalized to inventory and recorded through cost of sales unless the stripping activity can be shown to improve access to further quantities of ore that will be mined in future periods, in which case, the stripping costs are capitalized to property, plant and equipment. Capitalized stripping costs are included in "mining properties" within property, plant and equipment. Capitalized stripping costs are depreciated using a units-of-production method over the expected reserves within a given phase of mine development.
Impairment of non-financial assets [Policy Text Block]	(j) financial assets: At the end of each reporting period, Hudbay reviews the carrying amounts of property, plant and equipment, exploration and evaluation assets and intangible assets - computer software to determine whether there is any indication of impairment. If any such indication exists, the Company estimates the recoverable amount of the asset in order to determine the extent of the impairment loss, if any. Hudbay generally assesses impairment at the level of CGUs, which are the smallest identifiable groups of assets that generate cash inflows that are largely independent of cash inflows from other assets. Hudbay's CGUs consist of Manitoba, Peru, Arizona and greenfield exploration and evaluation assets. The Company allocates near mine exploration and evaluation assets to CGUs based on their operating segment, geographic location and management's intended use for the property. Near mine exploration and evaluation assets are allocated to CGUs separate from those containing producing or development-phase assets, except where such exploration and evaluation assets have the potential to significantly affect the future production of producing or development-phase assets. Goodwill, if recorded, is tested for impairment annually and whenever there is an indication that the asset may be impaired. Where an indicator of impairment exists, a formal estimate of the recoverable amount of the asset or CGU is made. The recoverable amount is the higher of the fair value less costs of disposal and value in use: - - Hudbay estimates future cash flows based on estimated future recoverable mine production, expected sales prices (considering current and historical commodity prices, price trends and related factors), production levels and cash costs of production, all based on detailed engineering LOM plans. Future recoverable mine production is determined from reserves and resources after taking into account estimated dilution and recoveries during mining, and estimated losses during ore processing and treatment. Estimates of recoverable production from measured, indicated and inferred mineral resources not included in the LOM plan are assessed for economic recoverability and may also be included in the valuation of fair value less costs of disposal. Gains from the expected disposal of assets are not included in estimated future cash flows. Assumptions underlying future cash flow estimates are subject to risks and uncertainties. Changes in estimates may affect the expected recoverability of the Company's investments in mining properties. If the carrying amount of an asset or CGU exceeds its recoverable amount, the carrying amount is reduced to the recoverable amount, and an impairment loss is recognized in the consolidated income statements in the expense category consistent with the function of the impaired asset or CGU. Hudbay presents impairment losses on the consolidated income statements as part of results from operating activities. Impairment losses recognized in respect of a CGU are allocated first to reduce the carrying amount of any goodwill allocated to the CGU and then to reduce the carrying amounts of other assets in the CGU on a pro-rata basis for depreciable assets. The Company assesses previously recognized impairment losses each reporting date for any indications that the losses have decreased or no longer exist. Such an impairment loss is reversed, in full or in part, if there have been significant changes with a positive effect on the estimates used to determine the recoverable amount. An impairment loss is reversed only to the extent that the asset's carrying amount does not exceed the carrying amount that would have been determined, net of depreciation or amortization, if no impairment loss had been recognized for the asset in prior years. Such reversals of impairment losses are recognized in the consolidated income statements. An impairment loss recognized in relation to goodwill is not reversed for subsequent increases in the recoverable amount.
Assets held for sale [Policy Text Block]	(k) Assets held for sale: The Company classifies non-current assets, or disposal groups consisting of assets and liabilities, as held for sale when it expects to recover their carrying amounts primarily through sale rather than through continuing use. To meet criteria to be held for sale, the sale must be highly probable, and the assets or disposal groups must be available for immediate sale in their present condition. Hudbay must be committed to a plan to sell the assets or disposal group, and the sale should be expected to qualify for recognition as a completed sale within one year from the date of classification. The Company measures assets or disposal groups at the lower of their carrying amount and fair value less costs of disposal. Impairment losses on initial classification as held for sale and subsequent gains and losses on remeasurement are recognized in the consolidated income statements; however, gains are not recognized in excess of any cumulative impairment loss. Any impairment loss on a disposal group first is allocated to goodwill, and then to remaining assets and liabilities on pro rata basis, except that no loss is allocated to inventories, financial assets, deferred tax assets, employee benefit assets or investment property. Upon classifying assets or disposal groups as held for sale, Hudbay presents the assets separately as a single amount and the liabilities separately as a single amount on the consolidated balance sheets. When an asset no longer meets the criteria for classification as an asset held for sale, the Company records the asset at the lower of its recoverable amount and the carrying amount before the asset was classified as held for sale.
Pension and other employee benefits [Policy Text Block]	(l) Pension and other employee benefits: Hudbay has non-contributory and contributory defined benefit programs for the majority of its Canadian employees. The defined benefit pension benefits are based on years of service and final average salary for the salaried plans and are based on a flat dollar amount combined with years of service for the hourly plans. The Company provides non pension health and other post-employment benefits to certain active employees and pensioners (post-employment benefits) and also provides disability income, health benefits and other post-employment benefits to hourly and salaried disabled employees (other long-term employee benefits). Hudbay accrues its obligations under the defined benefit plans as the employees render the services necessary to earn the pension and post-employment benefits. The actuarial determination of the accrued benefit obligations for pensions and post-employment benefits uses the projected benefit method pro-rated on service (which incorporates management's best estimate of future salary levels, other cost escalation, retirement ages of employees and other actuarial factors). For other long-term employee benefits, the Company recognizes the full cost of the benefit obligation at the time the employee becomes disabled. Actuarial advice is provided by external consultants. For the funded defined benefit plans, Hudbay recognizes the deficit or excess of the fair value of plan assets over the present value of the defined benefit obligation as a liability or an asset in the consolidated balance sheets. However, the Company recognizes an excess of assets only to the extent that it represents a future economic benefit which is available in the form of refunds from the plan or reductions in future contributions to the plan. When these criteria are not met, it is not recognized but is disclosed in the notes to the consolidated financial statements. Impacts of minimum funding requirements in relation to past service are considered when determining the balance sheet position. Defined benefit costs are categorized as follows: - - - The first two components of defined benefit costs shown above are recognized in the consolidated income statements. Past service cost is recognized in the consolidated income statements in the period of a plan amendment. Net interest is calculated by applying the discount rate at the beginning of the period to the net defined benefit liability or asset. Remeasurement, comprising actuarial gains and losses, the effect of changes to the asset ceiling (if applicable) and the return on plan assets (excluding interest), is reflected immediately in the consolidated balance sheets with a gain or loss recognized in OCI in the period in which they occur. Remeasurement recognized in OCI is reflected in the remeasurement reserve and will not be reclassified to the consolidated income statements. For the other long-term employee benefits plan, remeasurements are recognized immediately in the consolidated income statements. Actuarial determinations used in estimating obligations relating to these plans incorporate assumptions using management's best estimates of factors including plan performance, salary escalation, retirement dates of employees and healthcare cost escalation rates. Due to the complexity of the valuation, the underlying assumptions and its long-term nature, a defined benefit obligation is highly sensitive to changes in these assumptions. All assumptions are reviewed at each reporting date. In determining the appropriate discount rate, management considers the interest rates on corporate bonds in the respective currency with at least an AA rating, with extrapolated maturities corresponding to the expected duration of the defined benefit obligation. The mortality rate is based on publicly available mortality tables for the specific country. Future salary increases and pension increases are based on expected future inflation rates for the respective country. Hudbay also has defined contribution plans providing pension benefits for certain of its salaried employees and certain of its US employees utilizing 401K plans. The Company recognizes the cost of the defined contribution plans based on the contributions required to be made during each period. Termination benefits are recognized as an expense when Hudbay is committed demonstrably, without realistic possibility of withdrawal, to a formal detailed plan to either terminate employment before the normal retirement date, or to provide termination benefits as a result of an offer made to encourage voluntary redundancy. Termination benefits for voluntary redundancies are recognized as an expense if the Company has made an offer of voluntary redundancy, it is probable that the offer will be accepted, and the number of acceptances can be estimated reliably. Benefits that are payable more than one year after the reporting period are discounted to their present value.
Provisions [Policy Text Block]	(m) Provisions: Provisions are recognized when Hudbay has a present obligation (legal or constructive) as a result of a past event, it is probable that an outflow of resources will be required to settle the obligation, and a reliable estimate can be made. The provisions are recorded as management's best estimate of the amount required to settle an obligation. Provisions are stated at their present value, which is determined by discounting the expected future cash flows at a pre-tax rate that reflects current market assessments of the time value of money and the risks specific to the liability. Decommissioning, restoration and similar liabilities Provisions are recorded for legal and constructive obligations associated with the future costs of rehabilitating the Company's current and previous operating and development sites. Such costs are associated with decommissioning and restoration activities such as dismantling and removing structures, rehabilitating mines and tailings, and reclamation and re-vegetation of affected areas. The present value of estimated costs is recorded in the period in which the asset is installed or the environment is disturbed and a reasonable estimate of future costs and discount rates can be made. The provision is discounted using a risk-free rate, and estimates of future cash flows are adjusted to reflect risk. Subsequent to the initial measurement, the obligation is adjusted to reflect the passage of time and changes in the estimated future cash flows underlying the obligation. The increase in the provision due to the passage of time is recognized as finance expense, whereas increases and decreases due to changes in the estimated future cash flows, which are not the result of current inventory production, are capitalized and depreciated over the life of the related asset. Actual costs incurred upon settlement of the site restoration obligation are charged against the provision to the extent the provision was established for those costs. Upon settlement of the liability, a gain or loss may be recorded. For closed sites, changes to estimated costs are recognized immediately in the consolidated income statements within other operating expenses. Hudbay assesses the reasonableness of its estimates and assumptions each year and when conditions change, the estimates are revised accordingly. Judgement is required to determine the scope of future decommissioning and restoration activities, as well as best available estimates and assumptions including discount rates, expected timing of decommissioning and restoration costs, inflationary factors and market risks. Changes in cost estimates, which may arise from changes in technology and pricing of the individual components of the cost may result in offsetting changes to the asset and liability and corresponding changes to the associated depreciation and finance costs. In view of the uncertainties concerning these future obligations, the ultimate timing and cost of reclamation and mine closure may differ materially from these estimates. If the change in estimate results in a significant increase in the decommissioning liability and therefore an addition to the carrying value of the asset, the Company considers whether this is an indication of impairment of the asset as a whole and, if so, tests for impairment in accordance with IAS 36, Impairment of Assets. If, for mature mines, the revised mine assets net of decommissioning and restoration liabilities exceeds the recoverable value, that portion of the increase is charged directly to expense as an impairment loss. In view of the uncertainties concerning environmental remediation, the ultimate cost of decommissioning and restoration liabilities could differ materially from the estimated amounts provided. The estimate of the total liability is subject to change based on amendments to laws and regulations and as new information concerning Hudbay's operations becomes available. Future changes, if any, to the estimated total liability as a result of amended requirements, laws, regulations and operating assumptions, as well as discount rates, may be significant and would be recognized prospectively as a change in accounting estimate, when applicable. Environmental laws and regulations are continually evolving in all regions in which the Company operates. Hudbay is not able to determine the impact, if any, of environmental laws and regulations that may be enacted in the future on its results of operations or financial position due to the uncertainty surrounding the ultimate form that such future laws and regulations may take. Onerous contracts A contract is considered to be onerous when the unavoidable costs of meeting obligations under the contract exceed the economic benefits expected to be received under it. Hudbay records a provision for any onerous contracts at the lesser of costs to comply with a contract and costs to terminate it. Restructuring provisions A provision for restructuring is recognized when management, with appropriate authority within Hudbay, has approved a detailed and formal restructuring plan, and the restructuring has either commenced or has been announced publicly. Future operating costs are not provided for.
Financial Instruments [Policy Text Block]	(n) Financial instruments: Non-derivative financial instruments are initially recognized at fair value plus, in the case of a financial asset or financial liability not measured at fair value through profit or loss, directly attributable transaction costs. Measurement in subsequent periods depends on the financial instrument's classification. Hudbay uses trade date accounting for regular way purchases or sales of financial assets. The Company determines the classification of its financial instruments and non-financial derivatives at initial recognition. Financial assets and liabilities are offset and the net amount presented in the consolidated balance sheets when, and only when, Hudbay has a legal right to offset the amounts and intends either to settle on a net basis or to realize the asset and settle the liability simultaneously. The classification of financial assets is based on the results of the contractual characteristics test and the business model assessment which will result in the financial asset being classified as either: amortized cost, fair value through profit or loss ("FVTPL") or fair value through other comprehensive income ("FVTOCI"). i. Non-derivative financial instruments - classification: Financial assets at fair value through profit or loss Provisionally priced copper sales receivables, warrants and investments in securities of junior mining companies are classified as financial assets at fair value through profit or loss and are measured at fair value. The unrealized gains or losses related to changes in fair value are reported in other finance income/expense in the consolidated income statements. Amortized cost Cash, certain receivables, payables and restricted cash are classified as and measured at amortized cost and are carried at amortized cost using the effective interest rate method, less impairment losses, if any. Non-derivative financial liabilities Accounts payable and senior unsecured notes are initially recognized at fair value and subsequently accounted for at amortized cost, using the effective interest method. The amortization of senior unsecured notes issue costs is calculated using the effective interest rate method. ii. Derivatives: Derivatives are initially recognized at fair value when Hudbay becomes a party to the derivative contract and are subsequently re-measured to fair value at the end of each reporting period. The resulting gain or loss is recognized in the consolidated income statements immediately unless the derivative is designated and effective as a hedging instrument. Derivatives with positive fair value are recognized as assets; derivatives with negative fair value are recognized as liabilities. Contracts to buy or sell non-financial items that meet the definition of a derivative but were entered into and are held in accordance with the Company's expected purchase, sale or usage requirements are not recognized as derivatives. Such contracts are recorded as non-derivative purchases and sales. iii. Embedded derivatives: Hudbay considers whether a contract contains an embedded derivative when it becomes a party to the contract. Derivatives embedded in other financial liabilities or other host contracts are treated as separate derivatives when their risks and characteristics are not closely related to those of the host contracts and the host contracts are not measured at FVTPL. iv. Fair values of financial instruments: The fair value of a financial instrument is the amount for which an asset could be exchanged, or a liability settled, between knowledgeable, willing parties in an arm's length transaction. Fair values of financial instruments traded in active markets are determined based on quoted market prices, where available. Bid prices are generally used for assets held or liabilities to be issued; asking prices are generally used for assets to be acquired or liabilities held. For financial instruments not traded in an active market, fair values are determined based on appropriate valuation techniques. Such techniques may include discounted cash flow analysis, using recent arm's length market transactions, reference to the current fair value of another instrument that is substantially the same, and other valuation models. The Company applies a hierarchy to classify valuation methods used to measure financial instruments carried at fair value. Levels 1 to 3 are defined based on the degree to which fair value inputs are observable and have a significant effect on the recorded fair value, as follows: - Level 1: Quoted prices (unadjusted) in active markets for identical assets or liabilities; - Level 2: Valuation techniques use significant observable inputs, either directly (i.e. as prices) or indirectly (i.e. derived from prices), or valuations are based on quoted prices for similar instruments; and, - Level 3: Valuation techniques use significant inputs that are not based on observable market data (unobservable inputs). An analysis of fair values of financial instruments is provided in note 27. v. Impairment of financial instruments: Hudbay recognizes loss allowances for Expected Credit Losses ("ECL") for trade receivables not measured at FVTPL. Loss allowances for trade receivables are measured at an amount equal to lifetime ECL. ECL is a probability-weighted estimate measured at the present value of all cash shortfalls including the impact of forward-looking information. Hudbay has established a provision based on the Company's historical credit loss experience, adjusted for forward-looking factors specific to the debtors and the economic environment. The loss allowance is presented as a deduction to trade receivables in the balance sheets. vi. Derecognition of financial instruments: Hudbay derecognizes financial assets when the contractual rights to the cash flows from the assets expire, or when the Company transfers the rights to receive the contractual cash flows on the financial assets in a transaction in which substantially all the risks and rewards of ownership of the financial asset are transferred. Any interest in the transferred financial assets that is created or retained by Hudbay is recognized as a separate asset or liability. Hudbay derecognizes financial liabilities when its contractual obligations are discharged, cancelled or expire or when its terms are modified and the cash flows of the modified liability are substantially different.
Taxation [Policy Text Block]	(o) Taxation: Current Tax Current income tax assets and liabilities for the current and prior periods are measured at the amount expected to be recovered from or paid to the taxation authorities. The tax rates and tax laws used to compute the amount are those that are enacted or substantively enacted by the balance sheet date. Hudbay is subject to income taxes in numerous jurisdictions. Significant judgement is required in determining the worldwide provision for income taxes due to the complexity of legislation. There are many transactions and calculations for which the ultimate tax determination is uncertain during the ordinary course of business. The Company recognizes liabilities for anticipated tax issues based on estimates of whether additional taxes will be due. Where the final tax outcome of these matters is different from the amounts that were initially recorded, such differences will affect the income tax and deferred tax provisions in the period in which such determination is made. Additionally, future changes in tax laws in the jurisdictions in which Hudbay operates could limit the ability of the Company to obtain tax deductions in future periods. Deferred Tax Deferred tax is recognized using the balance sheet method in respect of temporary differences at the balance sheet date between the tax basis of assets and liabilities, and their carrying amounts for financial reporting purposes. Deferred income tax liabilities are recognized for all taxable temporary differences, except: - - Deferred income tax assets are recognized for all deductible temporary differences, carry-forward of unused tax assets and unused tax losses, to the extent that it is probable that taxable profit will be available against which the deductible temporary differences, and the carry-forward of unused tax assets and unused tax losses can be utilized, except: - - To the extent that it is probable that taxable profit will be available to offset the deductible temporary differences, Hudbay recognizes the deferred tax asset regarding the temporary difference on decommissioning, restoration and similar liabilities and recognizes the corresponding deferred tax liability regarding the temporary difference on the related assets. The carrying amount of deferred income tax assets is reviewed at each balance sheet date and reduced to the extent that it is no longer probable that sufficient taxable profit will be available to allow all or part of the deferred income tax asset to be utilized. Unrecognized deferred income tax assets are reassessed at each balance sheet date and are recognized to the extent that it has become probable that future taxable profit will be available to allow the deferred tax asset to be recovered. Judgement is required in determining whether deferred tax assets are recognized on the consolidated balance sheets. Deferred tax assets, including those arising from unutilized tax losses, require management to assess the likelihood of taxable profit in future periods in order to utilize recognized deferred tax assets. Estimates of future taxable income are based on forecast cash flows from operations and the application of existing tax laws in each jurisdiction. To the extent that future cash flows and taxable income differ significantly from estimates, the ability to realize the net deferred tax assets recorded at the balance sheet date could be affected. Deferred tax is measured on an undiscounted basis at the tax rates that are expected to apply in the periods in which the asset is realized or the liability is settled, based on tax rates and tax laws enacted or substantively enacted at the balance sheet date. Deferred income tax assets and deferred income tax liabilities are offset if a legally enforceable right exists to offset current tax assets against current tax liabilities and the deferred income taxes relate to the same taxable entity and the same taxation authority. Current and deferred taxes relating to items recognized outside profit or loss (whether in other comprehensive income or directly in equity) are recognized outside profit or loss and not in the consolidated income statements. Mining taxes and royalties are treated and disclosed as current and deferred taxes if they have the characteristics of an income tax.
Share capital and reserves [Policy Text Block]	(p) Share capital and reserves: Transaction costs Transaction costs directly attributable to equity transactions are recognized as a deduction from equity. Other capital reserve The other capital reserve is used for equity-settled share-based compensation and includes amounts for stocks options granted and not exercised. Foreign currency translation reserve The foreign currency translation reserve is used to record exchange differences arising from the translation of the financial statements of foreign operations. Exchange differences arising from the translation of the financial statements of foreign operations form part of the net investment in the foreign operation. Translation gains and losses remain in the reserve until disposal of all or a portion of the foreign operation.
Share-based payments [Policy Text Block]	(q) Share-based compensation: Hudbay offers a Deferred Share Unit ("DSU") plan for non-employee members of the Board of Directors, a Restricted Share Unit ("RSU") plan for employees, a Performance Share Unit ("PSU") plan for employees and a stock option plan for employees. These plans are included in provisions on the consolidated balance sheets and further described in note 24. Changes in the fair value of the liabilities are recorded in the consolidated income statements. Cash-settled transactions, consisting of DSUs, RSUs and PSUs, are initially measured at fair value and recognized as an obligation at the grant date. The liabilities are remeasured to fair value at each reporting date up to and including the settlement date, with changes in fair value recognized in the consolidated income statements. Hudbay values the liabilities based on the change in the Company's share price. Additional DSUs, RSUs and PSUs are credited to reflect dividends paid on Hudbay common shares over the vesting period. The current portion of the liability reflects those grants that have vested or that are expected to vest within twelve months. DSUs vest on the grant date and are redeemable when a participant is no longer a member of the Board of Directors. Issue and redemption prices of DSUs are based on the average closing price of the Company's common shares for the five trading days prior to issuance or redemption. RSUs and PSUs are issued under Hudbay's Long Term Equity Plan ("LTEP Plan") and vest on or before December 31st of the third calendar year after the year in which the services corresponding to such share unit award were performed. RSUs and PSUs granted under the LTEP Plan may be settled in the form of the Company's common shares or, at the option of Hudbay, the cash equivalent based on the market price of the common shares as of the vesting date. Hudbay has historically settled RSUs in cash. Except in specified circumstances, RSUs and PSUs terminate when an employee ceases to be employed by the Company. Valuations of RSUs and PSUs reflect estimated forfeitures. Equity-settled transactions with employees relate to stock options and are measured by reference to the fair value at the earlier of the grant date and the date that the employee unconditionally became entitled to the award. Fair value is determined using a Black-Scholes option pricing model, which relies on estimates of the future risk-free interest rate, future dividend payments, future share price volatility and the expected average life of the options. Hudbay believes this model adequately captures the substantive features of the option awards and is appropriate to calculate their fair values. The fair value determined at the grant date is recognized over the vesting period in accordance with vesting terms and conditions, with a corresponding increase to other capital reserves. The amount recognized as an expense is adjusted to reflect the number of awards for which the related service and non-market vesting conditions are expected to be met.
Earnings per share [Policy Text Block]	(r) The Company presents basic and diluted earnings (loss) per share ("EPS") data for its common shares. Basic EPS is calculated by dividing the profit or loss attributable to common shareholders of the Company by the weighted average number of common shares outstanding during the period. Diluted EPS is determined by adjusting the profit or loss attributable to common shareholders and the weighted average number of common shares outstanding for the effects of all dilutive potential common shares, which previously consisted of stock options granted to employees and warrants. When calculating earnings per share for periods where the Company has a loss, Hudbay's calculation of diluted earnings per share excludes any incremental shares from the assumed conversion of stock options as they would be anti-dilutive.
Leases [Policy Text Block]	(s) Leases, under which substantially all the risks and rewards incidental to ownership of the leased item are transferred to Hudbay, are capitalized as assets at the inception of the lease at the lower of fair value or the present value of the minimum lease payments. Lease payments are apportioned between finance charges and the reduction of the liability so as to achieve a constant periodic rate of interest on the remaining balance of the liability. Finance charges are reflected in the consolidated income statements as finance costs. Non-ROU lease payments are recognized as an expense in the consolidated income statements on a straight-line basis over the lease term.
Segment reporting [Policy Text Block]	(t) An operating segment is a component of the Company that engages in business activities from which it may earn revenue and incur expenses and for which discrete financial information is available. Hudbay's chief executive officer regularly reviews the operating results of each operating segment to make decisions about resources to be allocated to the segment and assess its performance. In determining operating segments, Hudbay considers location and decision-making authorities. Refer to note 31.
Statements of cash flows [Policy Text Block]	(u) Hudbay presents interest paid and dividends paid as financing activities, except if the interest is related to capitalized borrowing costs, and interest received is presented as an investing activity in the consolidated statement of cash flow. Hudbay presents the consolidated statement of cash flows using the indirect method.

Significant accounting polici_3

Significant accounting policies (Tables)	12 Months Ended
Significant accounting policies (Tables)	Dec. 31, 2020
Significant Accounting Policies [Abstract]
Disclosure of detailed information about estimated useful life or depreciation rate [Table Text Block]	• Capital works in progress - not depreciated • Mining properties - unit-of- production • Mining asset - unit-of- production • Plant and Equipment ◦ Equipment - straight-line over 1 to 20 years ◦ Other plant assets - straight-line over 1 to 20 years/unit-of-production • ROU Assets - straight -line over 1 to 20 years

Acquisition of remaining inte_2

Acquisition of remaining interest in the Rosemont project (Tables)	12 Months Ended
	Dec. 31, 2020
Disclosure of detailed information about business combination [abstract]
Disclosure of detailed information about acquisition date fair value of consideration paid [Table Text Block]	Cash $ 45,000 Present value of future cash installments 23,557 Total consideration $ 68,557
Disclosure of detailed information about acquisition of remaining asset and liabilities [Table Text Block]	Current assets $ 343 Non-current assets 68,904 Liabilities (690 ) Net assets acquired $ 68,557

Revenue and expenses (Tables)

Revenue and expenses (Tables)	12 Months Ended
Revenue and expenses (Tables)	Dec. 31, 2020
Analysis of income and expense [abstract]
Disclosure of detailed information about revenue [Table Text Block]	Year ended 2020 2019 Copper $ 563,910 $ 786,332 Zinc 264,106 284,897 Gold 180,949 120,366 Silver 25,986 29,315 Molybdenum 25,627 31,270 Other 5,619 4,760 1,066,197 1,256,940 Non-cash streaming arrangement items 1 Amortization of deferred revenue - gold 27,854 32,028 Amortization of deferred revenue - silver 39,409 60,370 Amortization of deferred revenue - variable 6,668 (16,295 ) 73,931 76,103 Pricing and volume adjustments 2 9,178 (12,123 ) 1,149,306 1,320,920 Treatment and refining charges (56,888 ) (83,481 ) $ 1,092,418 $ 1,237,439 1 2
Disclosure of depreciation and amortization expense [Table Text Block]	Year ended December 31, 2020 2019 Cost of sales $ 361,827 $ 344,555 Selling and administrative expenses 1,776 2,079 $ 363,603 $ 346,634
Disclosure of detailed information about share-based payment expenses (recoveries) [Table Text Block]	Cash-settled Total share-based compensation expense RSUs DSUs PSUs Stock options Year ended December 31, 2020 Cost of sales $ 1,400 $ — $ — $ — $ 1,400 Selling and administrative 4,872 5,149 1,987 1,122 13,130 Other expenses 478 — — — 478 $ 6,750 $ 5,149 $ 1,987 $ 1,122 $ 15,008 Year ended December 31, 2019 Cost of sales $ 400 $ — $ — $ — $ 400 Selling and administrative 928 1,157 — — 2,085 Other expenses 229 — — — 229 $ 1,557 $ 1,157 $ — $ — $ 2,714
Disclosure of detailed information about other operating expense [Table Text Block]	Year ended December 31, 2020 2019 Regional costs $ 3,602 $ 3,780 Loss on disposal of property, plant and equipment 5,088 4,807 Closure cost adjustment - non-producing properties 2,721 2,289 Allocation of community costs 2,880 2,216 Write down of UCM receivable — 25,978 Pampacancha delivery obligation — 7,499 Other 3,292 4,547 $ 17,583 $ 51,116
Disclosure of detailed information about impairment [Table Text Block]	Arizona Pre-tax impairment to: Property, plant & equipment $ 322,249 Tax impact - (recovery) (80,143 ) After-tax impairment charge $ 242,106
Disclosure of detailed information about employee benefits expense [Table Text Block]	Year ended December 31, 2020 2019 Current employee benefits $ 179,486 $ 171,173 Share-based compensation (notes 6c, 19, 24) Equity settled stock options 1,122 — Cash-settled restricted share units 6,750 1,557 Cash-settled deferred share units 5,149 1,157 Cash-settled performance share units 1,987 — Employee share purchase plan 1,783 1,645 Post-employee pension benefits Defined benefit plans 11,671 10,643 Defined contribution plans 1,774 1,635 Other post-retirement employee benefits 9,305 8,457 Termination benefits 582 628 $ 219,609 $ 196,895
Disclosure of detailed information about finance income and expenses [Table Text Block]	Year ended December 31, 2020 2019 Net interest expense on long-term debt Interest expense on long-term debt $ 82,712 $ 78,265 Interest capitalized — (9,890 ) 82,712 68,375 Accretion on streaming arrangements (note 18) Current year additions 60,362 63,725 Variable consideration adjustments - prior periods (3,692 ) 6,047 56,670 69,772 Change in fair value of financial assets and liabilities at fair value through profit or loss Embedded derivatives (45,387 ) 3,708 Gold prepayment liability 20,141 — Investments (4,124 ) 4,539 (29,370 ) 8,247 Other net finance costs Net foreign exchange (gains) losses (1,644 ) 1,388 Accretion on community agreements measured at amortized cost 3,641 1,222 Unwinding of discounts on provisions 3,543 4,392 Withholding taxes 8,267 8,100 Premium paid on redemption of notes (note 17) 7,252 — Write-down of unamortized transaction costs (note 17) 3,817 — Other finance expense 8,826 11,027 Interest income (1,812 ) (8,527 ) 31,890 17,602 Net finance expense $ 141,902 $ 163,996

Trade and other receivables (Ta

Trade and other receivables (Tables)	12 Months Ended
Trade and other receivables (Tables)	Dec. 31, 2020
Trade and other receivables [abstract]
Disclosure of detailed information about trade and other receivables [Table Text Block]	Dec. 31, 2020 Dec. 31, 2019 Current Trade receivables $ 107,787 $ 87,332 Statutory receivables 28,445 16,543 Other receivables 4,967 2,119 141,199 105,994 Non-current Taxes receivable 16,941 17,669 Other receivables 1,627 1,595 18,568 19,264 $ 159,767 $ 125,258

Inventories (Tables)

Inventories (Tables)	12 Months Ended
Inventories (Tables)	Dec. 31, 2020
Disclosure Of Inventories [Abstract]
Disclosure of detailed information about inventories [Table Text Block]	Dec. 31, 2020 Dec. 31, 2019 Current Stockpile $ 13,906 $ 10,396 Work in progress 6,364 14,420 Finished goods 72,923 62,230 Materials and supplies 49,912 51,774 143,105 138,820 Non-current Stockpile 16,704 14,626 Materials and supplies 5,302 4,829 22,006 19,455 $ 165,111 $ 158,275

Other financial assets (Tables)

Other financial assets (Tables)	12 Months Ended
Other financial assets (Tables)	Dec. 31, 2020
Disclosure of financial assets [abstract]
Disclosure of detailed information about other financial assets [Table Text Block]	Dec. 31, 2020 Dec. 31, 2019 Current Derivative assets $ 2,736 $ 1,712 Restricted cash 337 337 3,073 2,049 Non-current Investments at fair value through profit or loss 15,669 11,287 $ 18,742 $ 13,336

Intangibles and other assets (T

Intangibles and other assets (Tables)	12 Months Ended
Intangibles and other assets (Tables)	Dec. 31, 2020
Disclosure of detailed information about intangible assets [abstract]
Disclosure of detailed information about intangible assets [Table Text Block]	Dec. 31, 2020 Dec. 31, 2019 Cost Balance, beginning of year $ 21,538 $ 18,557 Additions 1,466 2,325 Disposals — (96 ) Effects of movement in exchange rates 346 752 Balance, end of year 23,350 21,538 Accumulated amortization Balance, beginning of year 16,511 14,395 Additions 1,138 1,606 Disposals — (96 ) Effects of movement in exchange rates 292 606 Balance, end of year 17,941 16,511 Intangibles, net book value $ 5,409 $

Property, plant and equipment (

Property, plant and equipment (Tables)	12 Months Ended
Property, plant and equipment (Tables)	Dec. 31, 2020
Disclosure of detailed information about property, plant and equipment [abstract]
Disclosure of detailed information about property, plant and equipment [Table Text Block]	Dec. 31, 2020 Exploration and evaluation assets Capital works in progress Mining properties Plant and equipment Plant and equipment- ROU assets Total Balance, Jan. 1, 2020 $ 69,903 $ 733,874 $ 2,146,583 $ 2,653,752 $ 201,972 $ 5,806,084 Additions 809 256,251 311 28,523 17,759 303,653 Capitalized stripping and development — — 83,137 — — 83,137 Decommissioning and restoration — 263 6,849 39,680 — 46,792 Interest capitalized — — — — — — Transfers and other movements 8,040 (36,668 ) (41,256 ) 70,777 (893 ) — Disposals — — — (19,681 ) (5,884 ) (25,565 ) Effects of movements in exchange rates 307 3,442 21,837 20,668 1,349 47,603 Balance, Dec. 31, 2020 79,059 957,162 2,217,461 2,793,719 214,303 6,261,704 Accumulated depreciation Balance, Jan. 1, 2020 — — 963,530 1,069,687 110,308 2,143,525 Depreciation for the year — — 146,113 200,632 23,351 370,096 Disposals — — — (14,038 ) (2,475 ) (16,513 ) Effects of movement in exchange rates — — 16,631 15,300 1,010 32,941 Balance, Dec. 31, 2020 — — 1,126,274 1,271,581 132,194 2,530,049 Net book value $ 79,059 $ 957,162 $ 1,091,187 $ 1,522,138 $ 82,109 $ 3,731,655 Dec. 31, 2019 Exploration and evaluation assets Capital works in progress Mining properties Plant and equipment Plant and equipment- ROU assets 1 Total Balance, January 1, 2019 $ 52,206 $ 873,781 $ 1,998,439 $ 2,473,176 $ 180,151 $ 5,577,753 Additions 17,016 109,372 — 33,309 22,158 181,855 Acquisitions (note 5) — 91,332 3,157 — 373 94,862 Capitalized stripping and development — — 103,108 — — 103,108 Decommissioning and restoration — 41 3,314 86,053 — 89,408 Interest capitalized — 9,890 — — — 9,890 Transfers and other movements — (30,000 ) 642 30,406 (1,048 ) — Impairments (note 6e) — (322,249 ) — — — (322,249 ) Disposals — (2,029 ) — (10,747 ) (1,533 ) (14,309 ) Effects of movements in exchange rates 681 1,528 41,080 38,452 1,793 83,534 Other — 2,208 (3,157 ) 3,103 78 2,232 Balance, Dec. 31, 2019 69,903 733,874 2,146,583 2,653,752 201,972 5,806,084 Accumulated depreciation Balance, January 1, 2019 — — 780,754 872,330 89,877 1,742,961 Depreciation for the year — — 154,970 179,062 19,850 353,882 Disposals — — — (6,675 ) — (6,675 ) Effects of movement in exchange rates — — 27,806 24,970 581 53,357 Balance, Dec. 31, 2019 — — 963,530 1,069,687 110,308 2,143,525 Net book value $ 69,903 $ 733,874 $ 1,183,053 $ 1,584,065 $ 91,664 $ 3,662,559

Trade and other payables (Table

Trade and other payables (Tables)	12 Months Ended
Trade and other payables (Tables)	Dec. 31, 2020
Trade and other payables [abstract]
Disclosure of detailed information about trade and other payables [Table Text Block]	Dec. 31, 2020 Dec. 31, 2019 Trade payables $ 104,598 $ 68,742 Accruals and payables 72,698 80,375 Accrued interest 30,766 34,603 Exploration and evaluation payables 1,351 884 Statutory payables 23,734 7,800 $ 233,147 $ 192,404

Other liabilities (Tables)

Other liabilities (Tables)	12 Months Ended
Other liabilities (Tables)	Dec. 31, 2020
Miscellaneous current liabilities [abstract]
Disclosure of detailed information about other current liabilities [Table Text Block]	Dec. 31, 2020 Dec. 31, 2019 Current Provisions (note 19) $ 33,675 $ 33,575 Pension liability (note 20) 13,552 12,015 Other employee benefits (note 21) 3,154 2,806 Unearned revenue 1,590 1,015 $ 51,971 $ 49,411

Other financial liabilities (Ta

Other financial liabilities (Tables)	12 Months Ended
Other financial liabilities (Tables)	Dec. 31, 2020
Disclosure of financial liabilities [abstract]
Disclosure of detailed information about other financial liabilities [Table Text Block]	Dec. 31, 2020 Dec. 31, 2019 Current Derivative liabilities $ 15,312 $ 10,295 Embedded derivatives (note 27d) — 9,074 Other financial liabilities at amortized cost 9,401 8,707 24,713 28,076 Non-current Deferred Rosemont acquisition consideration 25,961 24,491 Gold prepayment liability 137,031 — Other financial liabilities at amortized cost 31,386 15,293 194,378 39,784 $ 219,091 $ 67,860
Disclosure of detailed information about changes in other financial liabilities at amortized cost [Table Text Block]	Balance, January 1, 2019 $ 21,361 Net additions 7,369 Disbursements (6,351 ) Accretion 1,222 Effects of changes in foreign exchange 399 Balance, December 31, 2019 $ 24,000 Net additions 116,233 Disbursements (98,375 ) Accretion 3,641 Effects of changes in foreign exchange (4,712 ) Balance, December 31, 2020 $ 40,787

Lease Liability (Tables)

Lease Liability (Tables)	12 Months Ended
Lease Liability (Tables)	Dec. 31, 2020
Lease liabilities [abstract]
Disclosure of detailed information about leasing activities for lessee [Table Text Block]	Balance, January 1, 2019 $ 89,215 Additional capitalized leases (note 12) 22,158 Lease payments (32,952 ) Accretion and other movements 3,526 Balance, December 31, 2019 $ 81,947 Additional capitalized leases (note 12) 17,759 Lease payments (35,980 ) Accretion and other movements (212 ) Balance, December 31, 2020 $ 63,514 Dec. 31, 2020 Dec. 31, 2019 Current $ 33,473 $ 32,781 Non-current 30,041 49,166 $ 63,514 $ 81,947
Disclosure of detailed information about expenses recognized to leases for which exemption applied [Table Text Block]	Year ended 2020 2019 Short-term leases $ 40,253 $ 45,745 Low value leases 353 92 Variable leases 57,389 56,152 Total $ 97,995 $ 101,989

Long-term debt (Tables)

Long-term debt (Tables)	12 Months Ended
Long-term debt (Tables)	Dec. 31, 2020
Disclosure of detailed information about borrowings [line items]
Disclosure of borrowings [Table Text Block]	Dec. 31, 2020 Dec. 31, 2019 Senior unsecured notes (a) $ 1,139,695 $ 991,558 Less: Unamortized transaction costs - revolving credit facilities (b) (4,020 ) (6,303 ) $ 1,135,675 $ 985,255
Senior unsecured notes [Member]
Disclosure of detailed information about borrowings [line items]
Disclosure of detailed information about borrowings [Table Text Block]	Balance, January 1, 2019 $ 989,306 Change in fair value of embedded derivative (prepayment option) 1,079 Accretion of transaction costs and premiums 1,173 Balance, December 31, 2019 $ 991,558 Addition to Principal, net of $8,176 transaction costs 591,824 Principal repayments (400,000 ) Change in fair value of embedded derivative (prepayment option) (47,169 ) Write-down of unamortized transaction costs 2,315 Accretion of transaction costs and premiums 1,167 Balance, December 31, 2020 $ 1,139,695
Unamortized transaction costs - revolving credit facilities [Member]
Disclosure of detailed information about borrowings [line items]
Disclosure of detailed information about unamortized transaction costs revolving credit facilities [Table Text Block]	Balance, January 1, 2019 $ 8,276 Accretion of transaction costs (2,342 ) Transaction costs 369 Balance, December 31, 2019 $ 6,303 Accretion of transaction costs (3,062 ) Write-down of unamortized transaction costs (1,502 ) Transaction costs 2,281 Balance, December 31, 2020 1 $ 4,020 1

Deferred revenue (Tables)

Deferred revenue (Tables)	12 Months Ended
Deferred revenue (Tables)	Dec. 31, 2020
Disclosure Of Deferred Revenue [Abstract]
Disclosure of detailed information about changes in deferred revenue [Table Text Block]	Balance, January 1, 2019 $ 566,078 Amortization of deferred revenue Liability drawdown (92,398 ) Variable consideration adjustments - prior periods 16,295 Accretion on streaming arrangements Current year additions 63,725 Variable consideration adjustments - prior periods 6,047 Effects of changes in foreign exchange 4,009 Balance, December 31, 2019 $ 563,756 Amortization of deferred revenue Liability drawdown (67,263 ) Variable consideration adjustments - prior periods (6,668 ) Accretion on streaming arrangements (note 6g) Current year additions 60,362 Variable consideration adjustments - prior periods (3,692 ) Effects of changes in foreign exchange 189 Balance, December 31, 2020 $ 546,684
Disclosure of detailed information about deferred revenue [Table Text Block]	Dec. 31, 2020 Dec. 31, 2019 Current $ 102,782 $ 86,933 Non-current 443,902 476,823 $ 546,684 $ 563,756

Provisions (Tables)

Provisions (Tables)	12 Months Ended
Provisions (Tables)	Dec. 31, 2020
Disclosure of other provisions [abstract]
Disclosure of detailed information about changes in provisions [Table Text Block]	Decommis- sioning, restoration and similar liabilities Deferred share units (note 24a) Restricted share units 1 (note 24a) Performan- ce share units (note 24a) Other Total Balance, January 1, 2020 $ 302,116 $ 3,876 $ 5,477 $ — $ 2,956 $ 314,425 Net additional provisions made 5,868 1,628 3,642 1,257 15 12,410 Amounts used (18,737 ) (497 ) (2,646 ) — (1,824 ) (23,704 ) Unwinding of discount (note 6g) 3,543 — — — — 3,543 Effect of change in discount rate 43,180 — — — — 43,180 Effect of foreign exchange 7,162 191 116 43 (3 ) 7,509 Effect of change in share price — 3,521 3,860 730 — 8,111 Balance, December 31, 2020 $ 343,132 $ 8,719 $ 10,449 $ 2,030 $ 1,144 $ 365,474 Decommis-sioning, restoration and similar liabilities Deferred share units (note 24a) Restricted share units 1 Performance share units (note 24a) Other Total Balance, January 1, 2019 $ 202,024 $ 4,288 $ 12,201 $ — $ 411 $ 218,924 Net additional provisions made 68,881 1,479 2,885 — 2,882 76,127 Amounts used (4,136 ) (1,668 ) (9,380 ) — (341 ) (15,525 ) Unwinding of discount (note 6g) 4,392 — — — — 4,392 Effect of change in discount rate 23,635 — — — — 23,635 Effect of foreign exchange 7,320 99 225 — 4 7,648 Effect of change in share price — (322 ) (454 ) — — (776 ) Balance, December 31, 2019 $ 302,116 $ 3,876 $ 5,477 $ — $ 2,956 $ 314,425 1
Disclosure of detailed information about provisions [Table Text Block]	December 31, 2020 Decommis-sioning, restoration and similar liabilities Deferred share units (note 24a) Restricted share units 1 (note 24a) Performance share units (note 24a) Other Total Current (note 14) $ 20,308 $ 8,719 $ 4,648 $ — $ — $ 33,675 Non-current 322,824 — 5,801 2,030 1,144 331,799 $ 343,132 $ 8,719 $ 10,449 $ 2,030 $ 1,144 $ 365,474

Pension obligations (Tables)

Pension obligations (Tables)	12 Months Ended
Pension obligations (Tables)	Dec. 31, 2020
Pension Obligations [Abstract]
Disclosure of additional information about defined benefit plans [Table Text Block]	Year ended Dec. 31, 2020 Dec. 31, 2019 Opening defined benefit obligation: $ 243,733 $ 211,512 Current service costs 11,044 9,880 Interest cost 6,569 7,156 Benefits paid from plan (35,384 ) (16,745 ) Benefits paid from employer (1,317 ) (934 ) Participant contributions 48 64 Effects of movements in exchange rates 2,780 11,660 Remeasurement actuarial (gains)/losses: Arising from changes in demographic assumptions (1,461 ) — Arising from changes in financial assumptions 16,967 29,609 Arising from experience adjustments (2,625 ) (2,258 ) Settlement payments from plan assets — (6,307 ) Loss on settlement — 96 Closing defined benefit obligation $ 240,354 $ 243,733
Disclosure of detailed information about defined benefit plans, balance by member group [Table Text Block]	Dec. 31, 2020 Dec. 31, 2019 Active members $ 211,861 $ 231,959 Deferred members 2,198 1,555 Retired members 26,295 10,219 Closing defined benefit obligation $ 240,354 $ 243,733
Disclosure of detailed information about changes in fair value of plan assets [Table Text Block]	Year ended Dec. 31, 2020 Dec. 31, 2019 Opening fair value of plan assets: $ 202,119 $ 175,795 Interest income 5,695 6,170 Remeasurement adjustment: Return on plan assets (excluding amounts included in net interest expense) 15,377 21,460 Contributions from the employer 12,987 11,952 Employer direct benefit payments 1,317 934 Contributions from plan participants 48 64 Benefit payment from employer (1,317 ) (934 ) Administrative expenses paid from plan assets (77 ) (82 ) Benefits paid (35,384 ) (16,745 ) Settlement payments from plan assets — (6,307 ) Effects of changes in foreign exchange rates 2,721 9,812 Closing fair value of plan assets $ 203,486 $ 202,119
Disclosure of detailed information about net defined benefit liability (asset) [Table Text Block]	Dec. 31, 2020 Dec. 31, 2019 Present value of funded defined benefit obligation $ 220,210 $ 224,364 Fair value of plan assets (203,486 ) (202,119 ) Present value of unfunded defined benefit obligation 20,144 19,369 Net liability arising from defined benefit obligation $ 36,868 $ 41,614
Disclosure of detailed information about pension obligation [Table Text Block]	Dec. 31, 2020 Dec. 31, 2019 Pension obligation - current (note 14) $ 13,552 $ 12,015 Pension obligation - non-current 23,316 29,599 Total pension obligation $ 36,868 $ 41,614
Disclosure of detailed information about pension expense [Table Text Block]	Dec. 31, 2020 Dec. 31, 2019 Service costs: Current service cost $ 11,044 $ 9,880 Loss on settlement — 96 Total service cost 11,044 9,976 Net interest expense 874 986 Administration cost 77 82 Defined benefit pension expense $ 11,995 $ 11,044 Defined contribution pension expense $ 1,791 $ 1,639
Disclosure of detailed information about remeasurement on the net defined benefit liability [Table Text Block]	Dec. 31, 2020 Dec. 31, 2019 Return on plan assets (excluding amounts included in net interest expense) $ (15,377 ) $ (21,460 ) Actuarial gains arising from changes in demographic assumptions (1,461 ) — Actuarial losses arising from changes in financial assumptions 16,967 29,609 Actuarial gains arising from experience adjustments (2,625 ) (2,258 ) Defined benefit (gain)/loss related to remeasurement $ (2,496 ) $ 5,891 Total pension cost $ 11,290 $ 18,574
Disclosure of detailed information about defined benefit plan, assumptions used [Table Text Block]	2020 2019 Defined benefit cost: Discount rate - benefit obligations 3.08 % 3.73 % Discount rate - service cost 3.10 % 3.75 % Expected rate of salary increase 1 2.75 % 2.75 % Average longevity at retirement age for current pensioners (years) 2 Males 21.2 21.1 Females 23.9 23.9 Defined benefit obligation: Discount rate 2.54 % 3.08 % Expected rate of salary increase 1 2.75 % 2.75 % Average longevity at retirement age for current pensioners (years) 2 Males 20.3 21.2 Females 23.7 23.9 Average longevity at retirement age for current employees (future pensioners) (years) 2 Males 22.2 23.0 Females 25.4 25.6 1 2
Disclosure of fair value of plan assets [Table Text Block]	December 31, 2020 Level 1 Level 2 Level 3 Total Investments: Money market instruments $ 4,766 $ — $ — $ 4,766 Pooled equity funds 68,926 — — 68,926 Pooled fixed income funds — 98,922 — 98,922 Alternative investment funds — 30,323 — 30,323 Balanced funds — 549 — 549 $ 73,692 $ 129,794 $ — $ 203,486 December 31, 2019 Level 1 Level 2 Level 3 Total Investments: Money market instruments $ 1,588 $ — $ — $ 1,588 Pooled equity funds 76,680 — — 76,680 Pooled fixed income funds — 103,646 — 103,646 Alternative investment funds — 19,438 — 19,438 Balanced funds — 767 — 767 $ 78,268 $ 123,851 $ — $ 202,119

Other employee benefits (Tables

Other employee benefits (Tables)	12 Months Ended
Other employee benefits (Tables)	Dec. 31, 2020
Other Employee Benefits [Abstract]
Disclosure of detailed information about other employee benefit plans [Table Text Block]	Year ended Dec. 31, 2020 Dec. 31, 2019 Opening defined benefit obligation $ 116,696 $ 93,528 Current service cost 1 4,140 3,060 Past service cost — — Interest cost 3,478 3,600 Effects of movements in exchange rates 2,423 4,864 Remeasurement actuarial (gains)/losses: Arising from changes in demographic assumptions (4,460 ) — Arising from changes in financial assumptions 10,043 14,094 Arising from experience adjustments (489 ) 87 Benefits paid (2,215 ) (2,537 ) Closing defined benefit obligation $ 129,616 $ 116,696 1
Disclosure of detailed information about other employee benefit plans, balance by member group [Table Text Block]	Dec. 31, 2020 Dec. 31, 2019 Active members $ 68,983 $ 60,801 Inactive members 60,633 55,895 Closing defined benefit obligation $ 129,616 $ 116,696
Disclosure of detailed information about changes in fair value of assets of other employee benefits plan [Table Text Block]	Dec. 31, 2020 Dec. 31, 2019 Employer contributions $ 2,215 $ 2,537 Benefits paid (2,215 ) (2,537 ) Closing fair value of assets $ — $ —
Disclosure of detailed information about net benefit liability for other employee benefits [Table Text Block]	Dec. 31, 2020 Dec. 31, 2019 Unfunded benefit obligation $ 129,616 $ 116,696 Vacation accrual and other - non-current 3,046 2,888 Net liability $ 132,662 $ 119,584
Disclosure of detailed information about other employee benefits plan [Table Text Block]	Dec. 31, 2020 Dec. 31, 2019 Other employee benefits liability - current (note 14) $ 3,154 $ 2,806 Other employee benefits liability - non-current 129,508 116,778 Net liability $ 132,662 $ 119,584
Disclosure of detailed information about employee future benefit expense [Table Text Block]	Dec. 31, 2020 Dec. 31, 2019 Current service cost 1 $ 4,140 $ 3,060 Net interest cost 3,478 3,600 Components recognized in consolidated income statements $ 7,618 $ 6,660 1
Disclosure of detailed information about remeasurement of other long term employee benefits [Table Text Block]	Dec. 31, 2020 Dec. 31, 2019 Remeasurement on the net defined benefit liability: Actuarial gains arising from changes in demographic assumptions $ (4,460 ) $ — Actuarial losses arising from changes in financial assumptions 10,043 14,094 Actuarial (gains)/losses arising from changes experience adjustments (489 ) 87 Components recognized in statements of comprehensive income $ 5,094 $ 14,181 Total other employee future benefit cost $ 12,712 $ 20,841
Disclosure of detailed information about other employee benefit plan, assumptions used [Table Text Block]	Dec. 31, 2020 Dec. 31, 2019 Defined benefit cost: Discount rate 3.17 % 3.88 % Initial weighted average health care trend rate 5.68 % 5.74 % Ultimate weighted average health care trend rate 4.00 % 4.00 % Average longevity at retirement age for current pensioners (years) 1 Males 21.2 21.1 Females 23.9 23.9 Dec. 31, 2020 Dec. 31, 2019 Defined benefit obligation: Discount rate 2.76 % 3.17 % Initial weighted average health care trend rate 5.66 % 5.68 % Ultimate weighted average health care trend rate 4.00 % 4.00 % Average longevity at retirement age for current pensioners (years) 1 Males 20.3 21.2 Females 23.7 23.9 Average longevity at retirement age for current employees (future pensioners) (years) 1 Males 22.2 23.1 Females 25.4 25.6 1

Income and mining taxes (Tables

Income and mining taxes (Tables)	12 Months Ended
Income and mining taxes (Tables)	Dec. 31, 2020
Major components of tax expense (income) [abstract]
Disclosure of detailed information about effective income tax expense recovery [Table Text Block]	Year ended 2020 2019 Current: Income taxes $ 4,458 $ 24,919 Mining taxes 4,671 4,720 Adjustments in respect of prior years (398 ) 6,273 8,731 35,912 Deferred: Income tax recoveries - origination, revaluation and/or reversal of temporary differences (39,411 ) (133,468 ) Mining tax recoveries - origination, revaluation and/or reversal of temporary difference (3,331 ) (12,214 ) Adjustments in respect of prior years (494 ) 817 (43,236 ) (144,865 ) $ (34,505 ) $ (108,953 )
Disclosure of detailed information about deferred taxes [Table Text Block]	Dec. 31, 2020 Dec. 31, 2019 Deferred income tax asset $ 94,070 $ 69,950 Deferred mining tax asset 7,829 5,096 101,899 75,046 Deferred income tax liability (220,568 ) (233,218 ) Deferred mining tax liability (8,865 ) (9,710 ) (229,433 ) (242,928 ) Net deferred tax liability balance, end of year $ (127,534 ) $ (167,882 )
Disclosure of detailed information about changes in deferred tax assets and liabilities [Table Text Block]	Year ended Dec. 31, 2020 Year ended Net deferred tax liability balance, beginning of year $ (167,882 ) $ (308,577 ) Deferred tax recovery 43,236 144,865 OCI transactions (759 ) 1,878 Foreign currency translation on the deferred tax liability (2,129 ) (6,048 ) Net deferred tax liability balance, end of year $ (127,534 ) $ (167,882 )
Disclosure of detailed information about reconciliation to statutory tax rate [Table Text Block]	Year ended December 31, 2020 2019 Statutory tax rate 26.3 % 27.0 % Tax recovery at statutory rate $ (47,047 ) $ (122,246 ) Effect of: Deductions related to mining taxes (1,369 ) (1,493 ) Adjusted income taxes (48,416 ) (123,739 ) Mining tax expense (recovery) 1,291 (6,674 ) (47,125 ) (130,413 ) Permanent differences related to: Capital items (160 ) 3,270 Other income tax permanent differences (1,165 ) 1,747 Impact of remeasurement on decommissioning liability 7,094 (12,018 ) Temporary income tax differences not recognized (1,827 ) (351 ) Other temporary income tax differences not recognized 2,927 2,323 Non-deductible impairment on UCM receivable — 7,041 Withholding tax on dividends — 6,826 Impact related to differences in tax rates in foreign operations 5,534 20,338 Impact of changes to statutory tax rates 2,412 (259 ) Foreign exchange on non-monetary items (3,628 ) (6,633 ) Impact related to tax assessments and tax return amendments 1,433 (824 ) Tax recovery $ (34,505 ) $ (108,953 )
Disclosure of temporary differences recognized [Table Text Block]	Balance sheet Income Statement Dec. 31, 2020 Dec. 31, Dec. 31, 2020 Dec. 31, Deferred income tax (liability) asset/ expense (recovery) Property, plant and equipment $ (88,368 ) $ (96,841 ) $ (8,473 ) $ 13,434 Pension obligation 9,467 11,332 1,294 (1,115 ) Other employee benefits 25,687 16,837 (8,850 ) (3,349 ) Decommissioning and restoration obligation 37,902 41,208 3,307 (33,391 ) Non-capital losses 110,374 90,446 (19,928 ) (17,976 ) Share issuance and debt cost 8,972 6,540 (2,768 ) 4,361 Embedded derivative (prepayment option) (13,137 ) (694 ) 12,443 245 Deferred revenue (809 ) (112 ) 697 (12,839 ) Other 3,982 1,234 (4,516 ) (7,755 ) Deferred income tax asset / expense (recovery) 94,070 69,950 (26,794 ) (58,385 ) Deferred income tax liability (asset)/ (recovery) expense Property, plant and equipment 292,858 259,145 33,713 (79,892 ) Other employee benefits 203 (80 ) (176 ) (320 ) Asset retirement obligations (1,588 ) (833 ) (756 ) 85 Non-capital losses (78,607 ) (28,643 ) (49,965 ) (1,269 ) Other 7,702 3,629 4,073 7,302 Deferred income tax liability/ expense (recovery) 220,568 233,218 (13,111 ) (74,094 ) Deferred income tax liability/ expense (recovery) $ (126,498 ) $ (163,268 ) $ (39,905 ) $ (132,479 )
Disclosure of detailed information about temporary differences not recognized [Table Text Block]	Dec. 31, 2020 Dec. 31, 2019 Property, plant and equipment $ 46,718 $ 33,269 Capital losses 166,227 159,545 Other employee benefits 51,226 68,866 Asset retirement obligations 193,898 146,679 Non-capital losses 115,902 122,979 Temporary differences not recognized $ 573,971 $ 531,338
Disclosure of detailed information about temporary differences - deferred mining tax assets and liabilities [Table Text Block]	Dec. 31, 2020 Dec. 31, 2019 Canada Property, plant and equipment $ 7,829 $ 5,095 Dec. 31, 2020 Dec. 31, 2019 Peru Property, plant and equipment $ (8,865 ) $ (9,710 )

Share capital (Tables)

Share capital (Tables)	12 Months Ended
Share capital (Tables)	Dec. 31, 2020
Disclosure of classes of share capital [abstract]
Disclosure of detailed information about shares, activity [Table Text Block]	Year ended December 31, 2020 Year ended Common shares Amount Common shares Amount Beginning and 261,272,151 $ 1,777,340 261,272,151 $ 1,777,340

Share-based compensation (Table

Share-based compensation (Tables)	12 Months Ended
Share-based compensation (Tables)	Dec. 31, 2020
Disclosure of terms and conditions of share-based payment arrangement [line items]
Disclosure of fair value assumptions used in the Black Scholes valuation of share options [Table Text Block]	For options granted during the year ended Dec. 31, 2020 Weighted average share price at grant date (CAD) $ 3.77 Risk-free rate 1.14% Expected dividend yield 0.5% Expected stock price volatility (based on historical volatility) 57.0% Expected life of option (months) 84 Weighted average per share fair value of stock options granted (CAD) $ 2.02
Disclosure of range of exercise prices of outstanding share options [Table Text Block]	Dec. 31, 2020 Range of Number of Weighted Weighted Number of Weighted $3.76 - $3.92 1,563,189 6.16 $ 3.77 — $ —
Disclosure of number and weighted average exercise prices of share options [Table Text Block]	Year ended Year ended Dec. 31, 2020 Dec. 31, 2019 Number of shares subject to option Weighted- average exercise price C$ Number of shares subject to option Weighted average exercise price C$ Balance, beginning of year — — — $ — Number of units granted during the year 1,581,385 $ 3.77 — $ — Forfeited (18,196 ) $ 3.76 — $ — Balance, end of year 1,563,189 $ 3.77 — $ —
Deferred Share Unit [Member]
Disclosure of terms and conditions of share-based payment arrangement [line items]
Disclosure of detailed information about number and weighted average exercise prices of other equity instruments [Table Text Block]	Year ended Dec. 31, 2020 Dec. 31, 2019 Granted during the year: Number of units 465,889 337,999 Weighted average price (C$/unit) $ 4.10 $ 5.89 Expenses recognized during the year 1 $ 5,149 $ 1,157 Payments made during the year (note 19) $ 497 $ 1,668 1
Restricted Share Unit [Member]
Disclosure of terms and conditions of share-based payment arrangement [line items]
Disclosure of detailed information about number and weighted average exercise prices of other equity instruments [Table Text Block]	Year ended Dec. 31, 2020 Dec. 31, 2019 Number of units, beginning of year 1 2,223,999 3,666,867 Number of units granted during the year 1,388,786 1,080,741 Credits for dividends 17,587 7,554 Number of units forfeited during the year (44,678 ) (573,914 ) Number of units vested (645,357 ) (1,957,249 ) Number of units, end of year 1 2,940,337 2,223,999 Weighted average price - granted (C$/unit) $ 3.98 $ 8.98 Expenses recognized during the year 2 $ 6,750 $ 1,557 Payments made during the year (note 19) $ 2,646 $ 9,380
Performance Share Unit [Member]
Disclosure of terms and conditions of share-based payment arrangement [line items]
Disclosure of detailed information about number and weighted average exercise prices of other equity instruments [Table Text Block]	Year ended Dec. 31, 2020 Dec. 31, 2019 Number of units, beginning of year — — Number of units granted during the year 1,089,569 — Credits for dividends 6,046 — Number of units, end of year 1,095,615 — Weighted average price - granted (C$/unit) $ 3.97 $ — Expenses recognized during the year (note 6c) $ 1,987 $ — Payments made during the year (note 19) $ — $ —

Earnings per share (Tables)

Earnings per share (Tables)	12 Months Ended
Earnings per share (Tables)	Dec. 31, 2020
Basic earnings per share [abstract]
Disclosure of earnings per share [Table Text Block]	Year ended Dec. 31, 2020 Dec. 31, 2019 Basic and diluted weighted average common shares outstanding 261,272,151 261,272,151

Financial instruments (Tables)

Financial instruments (Tables)	12 Months Ended
Financial instruments (Tables)	Dec. 31, 2020
Disclosure of detailed information about financial instruments [abstract]
Disclosure of fair value measurement [Table Text Block]	Dec. 31, 2020 Dec. 31, 2019 FV CV FV CV Financial assets at amortized cost Cash and cash equivalents 1 $ 439,135 $ 439,135 $ 396,146 $ 396,146 Restricted cash 1 337 337 337 337 Fair value through profit or loss Trade and other receivables 1, 2, 3 114,381 114,381 91,046 91,046 Non-hedge derivative assets 4 2,736 2,736 1,712 1,712 Investments 5 15,669 15,669 11,287 11,287 Total financial assets 572,258 572,258 500,528 500,528 Financial liabilities at amortized cost Trade and other payables 1, 2 209,413 209,413 184,604 184,604 Deferred Rosemont acquisition consideration 8 25,961 25,961 24,491 24,491 Other financial liabilities 6 41,912 40,787 21,338 24,000 Senior unsecured notes 7 1,277,124 1,139,695 1,050,126 991,558 Fair value through profit or loss Embedded derivatives 4 — — 9,074 9,074 Gold prepayment liability 9 137,031 137,031 — — Non-hedge derivative liabilities 4 15,312 15,312 10,295 10,295 Total financial liabilities 1,706,753 1,568,199 1,299,928 1,244,022 Net financial liability $ (1,134,495 ) $ (995,941 ) $ (799,400 ) $ (743,494 ) 1 2 3 4 5 6 7 8 9
Disclosure of detailed information about significant unobservable inputs used in fair value measurement of assets and liabilities [Table Text Block]	December 31, 2020 Level 1 Level 2 Level 3 Total Financial assets measured at fair value Financial assets at FVTPL: Non-hedge derivatives $ — $ 2,736 $ — $ 2,736 Investments 15,669 — — 15,669 $ 15,669 $ 2,736 $ — $ 18,405 Financial liabilities measured at fair value Financial liabilities at FVTPL: Non-hedge derivatives $ — $ 15,312 $ — $ 15,312 Gold prepayment liability 1 — 137,031 — 137,031 Financial liabilities at amortized cost: Other financial liabilities — — 41,912 41,912 Senior unsecured notes 1,277,124 — — 1,277,124 $ 1,277,124 $ 152,343 $ 41,912 $ 1,471,379 1 December 31, 2019 Level 1 Level 2 Level 3 Total Financial assets measured at fair value Financial assets at FVTPL: Non-hedge derivatives $ — $ 1,712 $ — $ 1,712 Investments 11,287 — — 11,287 $ 11,287 $ 1,712 $ — $ 12,999 Financial liabilities measured at fair value Financial liabilities at FVTPL: Embedded derivatives $ — $ 9,074 $ — $ 9,074 Non-hedge derivatives — 10,295 — 10,295 Financial liabilities at amortized cost: Other financial liabilities — — 21,338 21,338 Senior unsecured notes 1,050,126 — — 1,050,126 $ 1,050,126 $ 19,369 $ 21,338 $ 1,090,833
Disclosure of detailed information about net position of contracts awaiting final pricing [Table Text Block]	Metal in concentrate Sales awaiting final pricing Average YTD price ($/unit) Unit Dec. 31, 2020 Dec. 31, 2019 Dec. 31, 2020 Dec. 31, 2019 Copper pounds (in thousands) 47,901 72,977 3.52 2.80 Gold oz 18,106 16,152 1,894 1,522 Silver oz 123,380 124,371 26.35 17.86
Disclosure of detailed information about foreign currency risk [Table Text Block]	Dec. 31, 2020 Dec. 31, 2019 CAD 1 USD 2 PEN 3 CAD 1 USD 2 PEN 3 Cash and cash equivalent $ 7,791 $ 3,895 $ 4,141 $ 8,394 $ 21,217 $ 7,617 Trade and other receivables 31 43,316 36,951 374 56,998 25,413 Other financial assets 15,669 — — 11,287 — — Trade and other payables (6,104 ) (1,419 ) (34,622 ) (5,719 ) (435 ) (22,618 ) Other financial liabilities — — (40,787 ) — — (24,000 ) $ 17,387 $ 45,792 $ (34,317 ) $ 14,336 $ 77,780 $ (13,588 ) 1 2 3
Disclosure of detailed information about sensitivity analysis for foreign currency risk [Table Text Block]	December 31, 2020 Change of: Would have changed 2020 after-tax profit by: USD/CAD exchange rate 1 + 10% $ 1.1 million USD/CAD exchange rate 1 - 10% (1.4 ) million USD/PEN exchange rate 2 + 10% 2.0 million USD/PEN exchange rate 2 - 10% (2.5 ) million December 31, 2019 Change of: Would have changed 2019 after-tax profit by: USD/CAD exchange rate 1 + 10% $ 3.4 million USD/CAD exchange rate 1 - 10% (4.1 ) million USD/PEN exchange rate 2 + 10% 0.8 million USD/PEN exchange rate 2 - 10% (1.0 ) million
Disclosure of detailed information about commodity price risk [Table Text Block]	December 31, 2020 Change of: Would have changed 2 020 after-tax profit by: Copper prices ($/lb) 3 + $0.30 $ (1.4) million Copper prices ($/lb) 3 — $0.30 1.4 million Zinc prices ($/lb) 4 + $0.10 0.3 million Zinc prices ($/lb) 4 — $0.10 (0.3) million December 31, 2019 Change of: Would have changed 2019 after-tax profit by: Copper prices ($/lb) 3 + $0.30 (2.0) million Copper prices ($/lb) 3 — $0.30 2.0 million Zinc prices ($/lb) 4 + $0.10 1.0 million Zinc prices ($/lb) 4 — $0.10 (1.0) million 3 4
Disclosure of detailed information about share price risk [Table Text Block]	December 31, 2020 Change of: Would have changed 2020 after-tax profit by: Share prices + 25% $ 3.9 million Share prices — 25% (3.9) million December 31, 2019 Change of: Would have changed 2019 after-tax profit by: Share prices + 25% $ 2.8 million Share prices — 25% (2.8) million
Disclosure of detailed information about interest rate risk [Table Text Block]	December 31, 2020 Change of: Would have changed 2020 after-tax profit by: Interest rates + 2.00% $ (38.0) million Interest rates — 2.00% 48.5 million December 31, 2019 Change of: Would have changed 2019 after-tax profit by: Interest rates + 2.00% $ 2.3 million Interest rates — 2.00% (2.6) million (ii) Credit risk
Disclosure of detailed information about liquidity risk [Table Text Block]	Dec. 31, 2020 Carrying amount Contractual cash flows 12 months or less 13 - 36 months 37 - 60 months More than 60 months Assets used to manage liquidity risk Cash and cash equivalents $ 439,135 $ 439,135 $ 439,135 — $ — $ — Restricted cash 337 337 337 — — — Trade and other receivables 114,381 114,381 114,381 — — — Non-hedge derivative assets 2,736 2,736 2,736 — — — $ 556,589 $ 556,589 $ 556,589 $ — $ — $ — Non-derivative financial liabilities Trade and other payables, including embedded derivatives $ (209,413 ) $ (209,413 ) $ (209,413 ) $ — $ — $ — Other financial 1 (40,787 ) (58,837 ) (12,097 ) (9,483 ) (6,578 ) (30,679 ) Deferred Rosemont acquisition consideration (25,961 ) (30,000 ) — (20,000 ) (10,000 ) — Long-term debt, including embedded derivatives (1,139,695 ) (1,726,904 ) (87,966 ) (168,188 ) (742,125 ) (728,625 ) Gold prepayment obligation (137,031 ) (137,031 ) — (137,031 ) — — $ (1,552,887 ) $ (2,162,185 ) $ (309,476 ) $ (334,702 ) $ (758,703 ) $ (759,304 ) Derivative financial liabilities Non hedge derivative contracts $ (15,312 ) $ (15,312 ) $ (15,312 ) $ — $ — $ — $ (15,312 ) $ (15,312 ) $ (15,312 ) $ — $ — $ — 1 Dec. 31, 2019 Carrying amount Contractual cash flows 12 months or less 13 - 36 months 37 - 60 months More than 60 months Assets used to manage liquidity risk Cash and cash equivalents $ 396,146 $ 396,146 $ 396,146 $ — $ — $ — Restricted cash 337 337 337 Trade and other receivables 91,046 91,046 89,451 — — 1,595 Non-hedge derivative assets 1,712 1,712 1,712 — — — $ 489,241 $ 489,241 $ 487,646 $ — $ — $ 1,595 Non-derivative financial liabilities Trade and other payables, including embedded derivatives $ (184,604 ) $ (184,604 ) $ (184,604 ) $ — $ — $ — Other financial 1 (24,000 ) (33,723 ) (6,672 ) (4,811 ) (4,734 ) (17,506 ) Deferred Rosemont acquisition consideration (24,491 ) (30,000 ) — (10,000 ) (20,000 ) — Long-term debt, including embedded derivatives (991,558 ) (1,350,540 ) (72,165 ) (149,500 ) (1,128,875 ) — $ (1,224,653 ) $ (1,598,867 ) $ (263,441 ) $ (164,311 ) $ (1,153,609 ) $ (17,506 ) Derivative financial liabilities Embedded derivative $ (9,074 ) $ (9,074 ) $ (9,074 ) $ — $ — $ — Non-hedge derivative contracts (10,295 ) (10,295 ) (10,295 ) — — — $ (19,369 ) $ (19,369 ) $ (19,369 ) $ — $ — $ — 1

Commitments and contingencies (

Commitments and contingencies (Tables)	12 Months Ended
Commitments and contingencies (Tables)	Dec. 31, 2020
Notes to Financial Statements [Abstract]
Disclosure of maturity analysis of operating lease payments [Table Text Block]	2020 2019 Within one year $ 58,173 $ 57,860 After one year but not more than five years 2,192 26,395 More than five years — — $ 60,365 $ 84,255

Related parties (Tables)

Related parties (Tables)	12 Months Ended
Related parties (Tables)	Dec. 31, 2020
Disclosure of transactions between related parties [abstract]
Disclosure of subsidiaries [Table Text Block]	Beneficial ownership of ultimate controlling party (Hudbay Minerals Inc.) Name Jurisdiction Business Entity's Parent 2020 2019 HudBay Marketing & Sales Inc. Canada Marketing and sales HMI 100% 100% HudBay Peru Inc. British Columbia Holding company HMI 100% 100% HudBay Peru S.A.C. Peru Exploration/development Peru Inc. 100% 100% HudBay (BVI) Inc. British Virgin Islands Precious metals sales Peru Inc. 100% 100% Hudbay Arizona Inc. British Columbia Holding company HMI 100% 100% Rosemont Copper Company Arizona Exploration/development HudBay Arizona (US) Holding Corporation 100% 100%
Disclosure of information about key management personnel [Table Text Block]	2020 2019 Short-term employee benefits 1 $ 7,951 $ 8,319 Post-employment benefits 639 762 Long-term share-based awards 6,381 6,966 $ 14,971 $ 16,047 1

Supplementary cash flow infor_2

Supplementary cash flow information (Tables)	12 Months Ended
Supplementary cash flow information (Tables)	Dec. 31, 2020
Supplementary Cash Flow Information [Abstract]
Disclosure of detailed information about supplemental cash flow information [Table Text Block]	Year ended 2020 2019 Change in: Trade and other receivables $ (37,720 ) $ 3,252 Other financial assets/liabilities 4,077 12,540 Inventories (2,867 ) (11,759 ) Prepaid expenses (3,722 ) (3,484 ) Trade and other payables 36,247 5,613 Provisions and other liabilities 1,602 (2,590 ) $ (2,383 ) $ 3,572

Segmented information (Tables)

Segmented information (Tables)	12 Months Ended
Segmented information (Tables)	Dec. 31, 2020
Disclosure of operating segments [abstract]
Disclosure of segments [Table Text Block]	Year ended December 31, 2020 Manitoba Peru Arizona Corporate and other activities Total Revenue from external customers $ 615,699 $ 476,719 $ — $ — $ 1,092,418 Cost of sales Mine operating costs 391,504 300,087 — — 691,591 Depreciation and amortization 177,552 184,275 — — 361,827 Gross profit (loss) 46,643 (7,643 ) — — 39,000 Selling and administrative expenses — — — 41,408 41,408 Exploration and evaluation expenses 6,491 6,295 3,870 540 17,196 Other expenses 8,382 4,901 2,066 2,234 17,583 Results from operating activities $ 31,770 $ (18,839 ) $ (5,936 ) $ (44,182 ) $ (37,187 ) Net interest expense on long term debt 82,712 Accretion on streaming arrangements 56,670 Change in fair value of financial instruments (29,370 ) Other net finance costs 31,890 Loss before tax (179,089 ) Tax recovery (34,505 ) Loss for the year $ (144,584 ) Year ended December 31, 2019 Manitoba Peru Arizona Corporate and other activities Total Revenue from external customers $ 537,421 $ 700,018 $ — $ — $ 1,237,439 Cost of sales Mine operating costs 385,159 356,183 — — 741,342 Depreciation and amortization 135,429 209,126 — — 344,555 Gross profit 16,833 134,709 — — 151,542 Selling and administrative expenses — — — 36,170 36,170 Exploration and evaluation expenses 18,476 5,804 — 6,494 30,774 Other expenses 8,201 14,022 28,149 744 51,116 Impairment loss — — 322,249 — 322,249 Results from operating activities $ (9,844 ) $ 114,883 $ (350,398 ) $ (43,408 ) $ (288,767 ) Net interest expense on long term debt 68,375 Accretion on streaming arrangements 69,772 Change in fair value of financial instruments 8,247 Other net finance costs 17,602 Loss before tax (452,763 ) Tax recovery (108,953 ) Loss for the year $ (343,810 )
Disclosure of segments, assets and liabilities [Table Text Block]	December 31, 2020 Manitoba Peru Arizona Corporate and other activities Total Total assets $ 801,691 $ 2,535,939 $ 718,982 $ 610,033 $ 4,666,645 Total liabilities 562,013 973,756 76,926 1,354,144 2,966,839 Property, plant and equipment 1 699,884 2,290,097 709,939 31,735 3,731,655 1 December 31, 2019 Manitoba Peru Arizona Corporate and other activities Total Total assets $ 779,896 $ 2,556,895 $ 700,799 $ 423,467 $ 4,461,057 Total liabilities 556,267 926,642 78,988 1,051,037 2,612,934 Property, plant and equipment 1 684,679 2,253,404 691,538 32,938 3,662,559 1
Disclosure of segments, additions to property, plant and equipment [Table Text Block]	December 31, 2020 Manitoba Peru Arizona Corporate and other activities Total Additions to property, plant and equipment $ 159,313 $ 208,805 $ 18,640 $ 32 $ 386,790 December 31, 2019 Manitoba Peru Arizona Corporate and other activities Total Additions to property, plant and equipment $ 143,418 $ 101,717 $ 38,923 $ 905 $ 284,963
Disclosure of geographical areas, revenue by customer location [Table Text Block]	2020 2019 Revenue by customer location 1 Canada $ 422,403 $ 418,636 China 215,278 158,795 United States 206,906 209,382 Philippines 77,575 71,506 Peru 56,437 110,411 Switzerland 55,703 162,167 Singapore 29,314 71,506 Germany 11,725 10,731 Other 17,077 24,305 $ 1,092,418 $ 1,237,439 1

Basis of preparation (Narrative

Basis of preparation (Narrative) (Details)	Apr. 25, 2019
United Copper And Moly L L C [Member] \| Rosemont Project [Member]
Basis Of Presentation [Line Items]
Percentage of voting equity interests acquired	7.95%

Acquisition of remaining inte_3

Acquisition of remaining interest in the Rosemont project (Narrative) (Details) - Rosemont Project [Member] - Agreement with United Copper & Moly LLC ("UCM") [Member] $ in Thousands	1 Months Ended
	Apr. 25, 2019USD ($)
Disclosure of detailed information about business combination [line items]
Percentage of voting equity interests acquired	7.95%
Upfront cash consideration paid	$ 45,000
Commitment to pay three annual installments of per year, commencing July 1, 2022	10,000
Loan receivable balance written off	$ 25,978
Percentage of ownership interest held	100.00%

Revenue and expenses (Narrative

Revenue and expenses (Narrative) (Details) $ in Thousands	12 Months Ended
Revenue and expenses (Narrative) (Details) $ in Thousands	Dec. 31, 2020USD ($)Share	Dec. 31, 2019USD ($)Share
Revenue And Expenses [Line Items]
Variable consideration adjustment	$ 6,668	$ (16,295)
Stock options granted \| Share	1,581,385	0
Impairment loss recognised in profit or loss, property, plant and equipment		$ 322,249
Employee share purchase plan, matching contribution, percentage	75.00%	75.00%
Bottom of range [member]
Revenue And Expenses [Line Items]
Employee share purchase plan, contributions, percentage of pre-tax base salary	1.00%	1.00%
Top of range [member]
Revenue And Expenses [Line Items]
Employee share purchase plan, contributions, percentage of pre-tax base salary	10.00%	10.00%
Manitoba [Member]
Revenue And Expenses [Line Items]
Profit sharing plan, percentage	10.00%	10.00%
Peru [Member]
Revenue And Expenses [Line Items]
Profit sharing plan, percentage	8.00%	8.00%

Inventories (Narrative) (Detail

Inventories (Narrative) (Details) - USD ($) $ in Thousands	12 Months Ended
Inventories (Narrative) (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Disclosure Of Inventories [Abstract]
Cost of inventories recognised as expense during period	$ 921,895	$ 978,810
Inventory write-down	$ 32	$ 504

Intangibles and other assets (N

Intangibles and other assets (Narrative) (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Disclosure of detailed information about intangible assets [abstract]
Intangibles and other assets	$ 21,173	$ 10,411
Other assets	15,764	5,384
Intangible assets other than goodwill	$ 5,409	$ 5,027

Property, plant and equipment_2

Property, plant and equipment (Narrative) (Details) $ in Thousands	9 Months Ended	12 Months Ended
	Sep. 30, 2019USD ($)$ / lbs	Dec. 31, 2020USD ($)	Dec. 31, 2019USD ($)
Disclosure of detailed information about property, plant and equipment [line items]
Impairment loss		$ 0	$ 322,249
Cash generating units [Member] \| Arizona [Member]
Disclosure of detailed information about property, plant and equipment [line items]
Impairment loss			$ 322,249
Discount rate applied to cash flow projections	9.50%
Cash flow calculations utilized long-term copper price \| $ / lbs	3.10
Cash flow calculations utilized molybdenum long-term prices \| $ / lbs	11
Recoverable amount of asset or cash-generating unit	$ 615,368
Amount by which unit's recoverable amount exceeds its carrying amount	$ 242,106

Other financial liabilities (Na

Other financial liabilities (Narrative) (Details) $ in Thousands	May 07, 2020USD ($)Ounce$ / OZ	Dec. 31, 2020USD ($)
Disclosure of financial liabilities [abstract]
Proceeds from gold prepayment	$ 115,005	$ 115,005
Gold ounces sold \| Ounce	79,954
Gold forward curve average price per ounce \| $ / OZ	1,682
Gains (losses) on financial liabilities at fair value through profit or loss		$ (22,026)

Lease Liability (Narrative) (De

Lease Liability (Narrative) (Details) - Finance lease obligations [Member]	Dec. 31, 2020
Bottom of range [member]
Disclosure of quantitative information about right-of-use assets [line items]
Borrowings, interest rate	1.95%
Top of range [member]
Disclosure of quantitative information about right-of-use assets [line items]
Borrowings, interest rate	5.44%

Long-term debt (Narrative) (Det

Long-term debt (Narrative) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Sep. 23, 2020	Aug. 31, 2020
Disclosure of detailed information about borrowings [line items]
Write-down of unamortized transaction costs	$ 3,817	$ 0
Premium paid on redemption of notes	7,252
Repayments of borrowings	400,000
Senior secured revolving credit facilities [Member]
Disclosure of detailed information about borrowings [line items]
Face amount of debt instruments	400,000			$ 550,000
Senior secured revolving credit facilities [Member] \| Peru [Member]
Disclosure of detailed information about borrowings [line items]
Letters of credit issued to support reclamation or pension obligations	24,796
Surety bonds issued to support reclamation obligations	20,000
Letters of credit	45,000
Senior secured revolving credit facilities [Member] \| Manitoba [Member]
Disclosure of detailed information about borrowings [line items]
Surety bonds issued to support reclamation obligations	90,295
Senior secured revolving credit facilities [Member] \| Arizona [Member]
Disclosure of detailed information about borrowings [line items]
Surety bonds issued to support reclamation obligations	8,591
Senior unsecured notes [Member]
Disclosure of detailed information about borrowings [line items]
Face amount of debt instruments	1,200,000
Write-down of unamortized transaction costs	2,315
Repayments of borrowings	$ 400,000
Senior Notes Due 2023 [Member]
Disclosure of detailed information about borrowings [line items]
Borrowings, interest rate	7.25%
Repayments of borrowings	$ 400,000
Senior Notes Due 2025 [Member]
Disclosure of detailed information about borrowings [line items]
Face amount of debt instruments	$ 600,000
Borrowings, interest rate	7.625%
Senior Notes Due 2029 [Member]
Disclosure of detailed information about borrowings [line items]
Face amount of debt instruments	$ 600,000		$ 600,000
Borrowings, interest rate	6.125%		6.125%
Unamortized transaction costs - revolving credit facilities [Member]
Disclosure of detailed information about borrowings [line items]
Write-down of unamortized transaction costs	$ 1,502

Deferred revenue (Narrative) (D

Deferred revenue (Narrative) (Details) $ in Thousands	12 Months Ended
Deferred revenue (Narrative) (Details) $ in Thousands	Dec. 31, 2020USD ($)$ / OZ	Dec. 31, 2019USD ($)$ / OZ	Nov. 04, 2013USD ($)	Aug. 08, 2012USD ($)
Disclosure of disaggregation of revenue from contracts with customers [line items]
Deposits from customers			$ 885,000
Description of additional deposit payments	In addition to the aggregate deposit payments of $885,000, as gold and silver is delivered under the stream agreements, Hudbay receives cash payments equal to the lesser of (i) the market price and (ii) $400 per ounce (for gold) and $5.90 per ounce (for silver), subject to 1% annual escalation after three years, from the inception of the agreement.
Amortization of deferred revenue - variable consideration adjustments - prior periods	$ 6,668	$ (16,295)
Accretion on streaming arrangements - variable consideration adjustments - prior periods	$ 3,692	$ (6,047)
Stream transactions with 777 mine [Member]
Disclosure of disaggregation of revenue from contracts with customers [line items]
Deposits from customers				$ 455,100
Drawdown rate for gold \| $ / OZ	1,173	1,177
Drawdown rate for silver \| $ / OZ	22.43	22.51
Stream transactions with Constancia mine [Member]
Disclosure of disaggregation of revenue from contracts with customers [line items]
Deposits from customers			$ 429,900
Drawdown rate for gold \| $ / OZ	976	948
Drawdown rate for silver \| $ / OZ	21.52	21.77

Provisions (Narrative) (Details

Provisions (Narrative) (Details)	Dec. 31, 2020	Dec. 31, 2019
Bottom of range [member]
Disclosure of other provisions [line items]
Provision estimates, discount rate used	0.12%	1.59%
Top of range [member]
Disclosure of other provisions [line items]
Provision estimates, discount rate used	1.65%	2.39%

Pension obligations (Narrative)

Pension obligations (Narrative) (Details) - Pension obligations [Member] $ in Thousands	12 Months Ended
	Dec. 31, 2020USD ($)Year	Dec. 31, 2019
Statements [Line Items]
Estimate of contributions expected to be paid to plan for next annual reporting period	$ 12,437
Weighted average duration of defined benefit obligation	21 years 2 months 12 days	19 years 3 months 18 days
Return on plan assets, percentage	10.80%	15.10%
Actuarial assumption of discount rates [Member]
Statements [Line Items]
Reasonably possible increase in actuarial assumption, basis points	50
Increase (decrease) in defined benefit obligation due to reasonably possible increase in actuarial assumption	$ (22,846)
Reasonably possible decrease in actuarial assumption, basis points	50
Increase (decrease) in defined benefit obligation due to reasonably possible decrease in actuarial assumption	$ 26,250
Actuarial assumption of expected rates of salary increases [Member]
Statements [Line Items]
Percentage of reasonably possible increase in actuarial assumption	1.00%
Increase (decrease) in defined benefit obligation due to reasonably possible increase in actuarial assumption	$ 3,526
Percentage of reasonably possible decrease in actuarial assumption	1.00%
Increase (decrease) in defined benefit obligation due to reasonably possible decrease in actuarial assumption	$ (3,158)
Actuarial assumptions of life expectancy [Member]
Statements [Line Items]
Reasonably possible increase in life expectancy (years) \| Year	1
Increase (decrease) in defined benefit obligation due to reasonably possible increase in actuarial assumption	$ 2,978
Reasonably possible decrease in life expectancy (years) \| Year	1
Increase (decrease) in defined benefit obligation due to reasonably possible decrease in actuarial assumption	$ (3,039)
Active members [Member]
Statements [Line Items]
Weighted average duration of defined benefit obligation	22 years 3 months 18 days	19 years 8 months 12 days
Deferred members [Member]
Statements [Line Items]
Weighted average duration of defined benefit obligation	21 years 10 months 24 days	22 years
Retired members [Member]
Statements [Line Items]
Weighted average duration of defined benefit obligation	12 years	10 years 6 months

Other employee benefits (Narrat

Other employee benefits (Narrative) (Details) - Other employee benefits [Member] $ in Thousands	12 Months Ended
	Dec. 31, 2020USD ($)Year	Dec. 31, 2019Year
Other Employee Benefits [Line Items]
Weighted average duration of non-pension post employment obligation \| Year	19.4	19.6
Actuarial assumption of discount rates [Member]
Other Employee Benefits [Line Items]
Reasonably possible increase in actuarial assumption, basis points	50
Increase (decrease) in defined benefit obligation due to reasonably possible increase in actuarial assumption	$ (11,585)
Reasonably possible decrease in actuarial assumption, basis points	50
Increase (decrease) in defined benefit obligation due to reasonably possible decrease in actuarial assumption	$ 13,392
Actuarial assumption of health care cost trend rates [Member]
Other Employee Benefits [Line Items]
Percentage of reasonably possible increase in actuarial assumption	1.00%
Increase (decrease) in defined benefit obligation due to reasonably possible increase in actuarial assumption	$ 27,392
Percentage of reasonably possible decrease in actuarial assumption	1.00%
Increase (decrease) in defined benefit obligation due to reasonably possible decrease in actuarial assumption	$ (21,023)
Actuarial assumptions of life expectancy [Member]
Other Employee Benefits [Line Items]
Reasonably possible increase in life expectancy (years) \| Year	1
Increase (decrease) in defined benefit obligation due to reasonably possible increase in actuarial assumption	$ 5,553
Reasonably possible decrease in life expectancy (years) \| Year	1
Increase (decrease) in defined benefit obligation due to reasonably possible decrease in actuarial assumption	$ (5,645)
Active members [Member]
Other Employee Benefits [Line Items]
Weighted average duration of non-pension post employment obligation \| Year	24.6	24.9
Inactive members [Member]
Other Employee Benefits [Line Items]
Weighted average duration of non-pension post employment obligation \| Year	13.6	13.9

Income and mining taxes (Narrat

Income and mining taxes (Narrative) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Disclosure of temporary difference, unused tax losses and unused tax credits [line items]
Deductible temporary differences for which no deferred tax asset is recognised	$ 573,971	$ 531,338
Description of expiry date of deductible temporary differences, unused tax losses and unused tax credits	The Canadian non-capital losses were incurred between 2006 and 2020 and expire between 2026 and 2040. Hudbay incurred United States net operating losses between 2004 and 2020 which have a twenty year carry forward period. Peruvian net operating losses were incurred in 2020 which have a four year carry forward period.
Mining tax effect of temporary differences recognized [Member]
Disclosure of temporary difference, unused tax losses and unused tax credits [line items]
Deductible temporary differences for which no deferred tax asset is recognised	$ 7,544	$ 5,361

Share capital (Narrative) (Deta

Share capital (Narrative) (Details) $ / shares in Units, $ in Thousands, $ in Thousands	1 Months Ended					12 Months Ended
	Feb. 18, 2021$ / shares	Sep. 25, 2020USD ($)	Mar. 27, 2020USD ($)	Sep. 27, 2019USD ($)	Mar. 29, 2019USD ($)	Dec. 31, 2020$ / shares	Dec. 31, 2020USD ($)	Dec. 31, 2019USD ($)	Mar. 26, 2021CAD ($)
Disclosure of classes of share capital [line items]
Dividends declared, amount per share \| $ / shares						$ 0.01
Dividends paid \| $		$ 1,979	$ 1,804	$ 1,972	$ 1,955		$ 3,783	$ 3,927
Dividends declared after reporting period [Member]
Disclosure of classes of share capital [line items]
Dividends declared, amount per share \| $ / shares	$ 0.01
Dividends declared \| $									$ 2,613

Share-based compensation (Narra

Share-based compensation (Narrative) (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2020USD ($)Shareshares	Dec. 31, 2019USD ($)Shareshares	Dec. 31, 2018Share
Disclosure of terms and conditions of share-based payment arrangement [line items]
Stock options granted \| Share	1,581,385	0
Stock options forfeited \| Share	18,196	0
Number of options outstanding \| Share	1,563,189	0	0
Deferred Share Unit [Member]
Disclosure of terms and conditions of share-based payment arrangement [line items]
Liability related to share unit plans \| $	$ 8,719	$ 3,876
Restricted Share Unit [Member]
Disclosure of terms and conditions of share-based payment arrangement [line items]
Liability related to share unit plans \| $	$ 10,449	$ 5,477
Restricted share units vested, but unreleased and unpaid \| shares	738,002	616,397
Performance Share Unit [Member]
Disclosure of terms and conditions of share-based payment arrangement [line items]
Liability related to share unit plans \| $	$ 2,030	$ 0
Stock option plan [Member]
Disclosure of terms and conditions of share-based payment arrangement [line items]
Description of stock option plan, number of options authorized	The Company's stock option plan was approved in June 2005 and amended in May 2008 (the "Plan"). Under the amended Plan, the Company may grant to employees, officers, directors or consultants of the Company or its affiliates options to purchase up to a maximum of 13 million common shares of Hudbay. The Company has determined that the appropriate accounting treatment is to classify the stock options as equity settled transactions.
Maximum number of common shares purchaseable under stock option plan \| shares	13,000,000

Earnings per share (Narrative)

Earnings per share (Narrative) (Details) - shares	12 Months Ended
Earnings per share (Narrative) (Details) - shares	Dec. 31, 2020	Dec. 31, 2019
Basic earnings per share [abstract]
Weighted average stock options with potential future dilutive effect not included in calculation of diluted earnings per share	1,292,840
Diluted weighted average common shares outstanding	261,272,151	261,272,151

Capital management (Narrative)

Capital management (Narrative) (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Statements [Line Items]
Long-term debt	$ 1,135,675	$ 985,255
Cash and cash equivalents	$ 439,135	$ 396,146	$ 515,497

Financial instruments (Narrativ

Financial instruments (Narrative) (Details) $ in Thousands, lb in Millions	12 Months Ended
	Dec. 31, 2020USD ($)lb$ / lbs	Dec. 31, 2019USD ($)lb$ / lbs
Disclosure of detailed information about financial instruments [line items]
Prepayment option - embedded derivative	$ 49,754	$ 2,585
Gold prepayment revaluation	$ (1,885)	$ 0
Pounds of copper fixed for floating swaps \| lb	43.4	66.1
Average price recorded for copper fixed for floating swaps \| $ / lbs	3.22	2.67
Pounds of zinc forward sales contracts \| lb	3.5	12.7
Derivative financial assets	$ 2,736	$ 1,712
Derivative financial liabilities	15,312	10,295
Aggregate fair value of other embedded derivatives		9,074
Precious metal credits delivered to settle liability	10,856
Gold prepayment liability	$ 137,031	$ 0
Deposits and other investments with Schedule 1 Canadian banks, as a percentage of total cash and cash equivalents	90.00%	92.00%
Percentage of entity's trade receivables that are insured	95.00%	96.00%
Credit insurance deductible	10.00%
Percentage of receivables that represent largest customers	56.00%	63.00%
Copper fixed for floating swaps [Member]
Disclosure of detailed information about financial instruments [line items]
Derivative financial liabilities	$ 13,198	$ 8,362
Non-hedge derivative zinc contracts [Member]
Disclosure of detailed information about financial instruments [line items]
Derivative financial assets	$ 622
Derivative financial liabilities		$ 221
Non-hedge derivative zinc contracts [Member] \| Bottom of range [member]
Disclosure of detailed information about financial instruments [line items]
Range of zinc forward sales contracts prices \| $ / lbs	0.87	1
Non-hedge derivative zinc contracts [Member] \| Top of range [member]
Disclosure of detailed information about financial instruments [line items]
Range of zinc forward sales contracts prices \| $ / lbs	1.30	1.15
Provisional pricing - copper and zinc [Member]
Disclosure of detailed information about financial instruments [line items]
Derivative financial assets	$ 21,295	$ 10,165

Commitments and contingencies_2

Commitments and contingencies (Narrative) (Details) $ in Thousands	Dec. 31, 2020USD ($)
Canada [Member]
Statements [Line Items]
Capital commitments	$ 22,539
Canada [Member] \| Amounts which can be terminated [Member]
Statements [Line Items]
Capital commitments	19,014
Peru [Member] \| Amounts which can be terminated [Member]
Statements [Line Items]
Capital commitments	39,078
Rosemont project in Arizona [Member]
Statements [Line Items]
Capital commitments	179,656
Rosemont project in Arizona [Member] \| Amounts which can be terminated [Member]
Statements [Line Items]
Capital commitments	$ 89,312

Supplementary cash flow infor_3

Supplementary cash flow information (Narrative) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Apr. 25, 2019
Supplementary Cash Flow Information [Line Items]
Increase to property, plant and equipment assets due to remeasurements of decommissioning and restoration liabilities	$ 46,792	$ 89,408
Additions	17,759	22,158
Plant and equipment- ROU assets [Member] \| Cost [Member]
Supplementary Cash Flow Information [Line Items]
Additions	17,759	22,158
Agreements With Communities [Member]
Supplementary Cash Flow Information [Line Items]
Additions	$ 116,233	$ 7,369
Rosemont Project [Member] \| Agreement with United Copper & Moly LLC ("UCM") [Member]
Supplementary Cash Flow Information [Line Items]
Loan receivable balance written off			$ 25,978

Segmented information (Narrativ

Segmented information (Narrative) (Details)	12 Months Ended
Segmented information (Narrative) (Details)	Dec. 31, 2020	Dec. 31, 2019
Customer 1 [Member]
Disclosure of major customers [line items]
Percentage of entity's revenue	36.00%	24.00%
Customer 2 [Member]
Disclosure of major customers [line items]
Percentage of entity's revenue	17.00%	9.00%
Customer 3 [Member]
Disclosure of major customers [line items]
Percentage of entity's revenue	13.00%	9.00%
Customer 4 [Member]
Disclosure of major customers [line items]
Percentage of entity's revenue	7.00%	8.00%
Customer 5 [Member]
Disclosure of major customers [line items]
Percentage of entity's revenue	7.00%	5.00%
Customer 6 [Member]
Disclosure of major customers [line items]
Percentage of entity's revenue	5.00%	5.00%
Customer 7 [Member]
Disclosure of major customers [line items]
Percentage of entity's revenue	5.00%
Customer 8 [Member]
Disclosure of major customers [line items]
Percentage of entity's revenue	5.00%

Events after the reporting pe_2

Events after the reporting period (Narrative) (Details) - Events after the reporting period [Member] Tonne in Millions	Sep. 30, 2021Ounce	Jun. 30, 2021Tonne
Pampacancha delivery obligation [Member]
Disclosure of non-adjusting events after reporting period [line items]
Tonnes of ore contracts no longer expects to mine \| Tonne		4
Stream transactions with Wheaton [Member]
Disclosure of non-adjusting events after reporting period [line items]
Additional ounces of gold required to be delivered \| Ounce	8,020

Significant accounting polici_4

Significant accounting policies (Schedule of detailed information about estimated useful life or depreciation rate explanatory) (Details)	12 Months Ended
	Dec. 31, 2020
Equipment [Member]
Disclosure of detailed information about property, plant and equipment [line items]
Useful lives or depreciation rates, property, plant and equipment	straight-line over 1 to 20 years
Other plant assets [Member]
Disclosure of detailed information about property, plant and equipment [line items]
Useful lives or depreciation rates, property, plant and equipment	straight-line over 1 to 20 years/unit-of-production
ROU Assets [Member]
Disclosure of detailed information about property, plant and equipment [line items]
Useful lives or depreciation rates, property, plant and equipment	straight -line over 1 to 20 years

Acquisition of remaining inte_4

Acquisition of remaining interest in the Rosemont project (Schedule of detailed information about consideration paid) (Details) - Rosemont Project [Member] - Agreement with United Copper & Moly LLC ("UCM") [Member] $ in Thousands	Apr. 25, 2019USD ($)
Disclosure of detailed information about business combination [line items]
Cash	$ 45,000
Present value of future cash installments	23,557
Total consideration	$ 68,557

Acquisition of remaining inte_5

Acquisition of remaining interest in the Rosemont project (Schedule of detailed information about assets acquired and liabilities assumed) (Details) - Rosemont Project [Member] - Agreement with United Copper & Moly LLC ("UCM") [Member] $ in Thousands	Apr. 25, 2019USD ($)
Disclosure of detailed information about business combination [line items]
Current assets	$ 343
Non-current assets	68,904
Liabilities	(690)
Net assets acquired	$ 68,557

Revenue and expenses (Schedule

Revenue and expenses (Schedule of detailed information about revenue) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Analysis of income and expense [abstract]
Copper	$ 563,910	$ 786,332
Zinc	264,106	284,897
Gold	180,949	120,366
Silver	25,986	29,315
Molybdenum	25,627	31,270
Other	5,619	4,760
Revenue from sale of goods	1,066,197	1,256,940
Non-cash streaming arrangement items
Amortization of deferred revenue - gold	27,854	32,028
Amortization of deferred revenue - silver	39,409	60,370
Amortization of deferred revenue - variable consideration adjustments - prior periods	6,668	(16,295)
Amortization of deferred revenue	73,931	76,103
Pricing and volume adjustments	9,178	(12,123)
Revenue excluding treatment and refining charges	1,149,306	1,320,920
Treatment and refining charges	(56,888)	(83,481)
Revenue	$ 1,092,418	$ 1,237,439

Revenue and expenses (Schedul_2

Revenue and expenses (Schedule of depreciation and amortization expense) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Revenue And Expenses [Line Items]
Depreciation and amortization	$ 363,603	$ 346,634
Cost of sales [Member]
Revenue And Expenses [Line Items]
Depreciation and amortization	361,827	344,555
Selling and administrative expenses [Member]
Revenue And Expenses [Line Items]
Depreciation and amortization	$ 1,776	$ 2,079

Revenue and expenses (Schedul_3

Revenue and expenses (Schedule of detailed information about share-based expense (recoveries) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Revenue And Expenses [Line Items]
Share-based compensation expenses	$ 15,008	$ 2,714
Cost of sales [Member]
Revenue And Expenses [Line Items]
Share-based compensation expenses	1,400	400
Selling and administrative expenses [Member]
Revenue And Expenses [Line Items]
Share-based compensation expenses	13,130	2,085
Other expenses [Member]
Revenue And Expenses [Line Items]
Share-based compensation expenses	478	229
Restricted Share Unit [Member]
Revenue And Expenses [Line Items]
Share-based compensation expenses	6,750	1,557
Restricted Share Unit [Member] \| Cost of sales [Member]
Revenue And Expenses [Line Items]
Share-based compensation expenses	1,400	400
Restricted Share Unit [Member] \| Selling and administrative expenses [Member]
Revenue And Expenses [Line Items]
Share-based compensation expenses	4,872	928
Restricted Share Unit [Member] \| Other expenses [Member]
Revenue And Expenses [Line Items]
Share-based compensation expenses	478	229
Deferred Share Unit [Member]
Revenue And Expenses [Line Items]
Share-based compensation expenses	5,149	1,157
Deferred Share Unit [Member] \| Cost of sales [Member]
Revenue And Expenses [Line Items]
Share-based compensation expenses	0	0
Deferred Share Unit [Member] \| Selling and administrative expenses [Member]
Revenue And Expenses [Line Items]
Share-based compensation expenses	5,149	1,157
Deferred Share Unit [Member] \| Other expenses [Member]
Revenue And Expenses [Line Items]
Share-based compensation expenses	0	0
Performance Share Unit [Member]
Revenue And Expenses [Line Items]
Share-based compensation expenses	1,987	0
Performance Share Unit [Member] \| Cost of sales [Member]
Revenue And Expenses [Line Items]
Share-based compensation expenses	0	0
Performance Share Unit [Member] \| Selling and administrative expenses [Member]
Revenue And Expenses [Line Items]
Share-based compensation expenses	1,987	0
Performance Share Unit [Member] \| Other expenses [Member]
Revenue And Expenses [Line Items]
Share-based compensation expenses	0	0
Stock Options [Member]
Revenue And Expenses [Line Items]
Share-based compensation expenses	1,122	0
Stock Options [Member] \| Cost of sales [Member]
Revenue And Expenses [Line Items]
Share-based compensation expenses	0	0
Stock Options [Member] \| Selling and administrative expenses [Member]
Revenue And Expenses [Line Items]
Share-based compensation expenses	1,122	0
Stock Options [Member] \| Other expenses [Member]
Revenue And Expenses [Line Items]
Share-based compensation expenses	$ 0	$ 0

Revenue and expenses (Schedul_4

Revenue and expenses (Schedule of other operating expenses) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Revenue And Expenses [Line Items]
Other operating expenses	$ 17,583	$ 51,116
Regional costs [Member]
Revenue And Expenses [Line Items]
Other operating expenses	3,602	3,780
Loss on disposal of property,plant & equipment [Member]
Revenue And Expenses [Line Items]
Other operating expenses	5,088	4,807
Closure cost adjustment - non-producing properties [Member]
Revenue And Expenses [Line Items]
Other operating expenses	2,721	2,289
Allocation of community costs [Member]
Revenue And Expenses [Line Items]
Other operating expenses	2,880	2,216
Write down of UCM receivable [Member]
Revenue And Expenses [Line Items]
Other operating expenses	0	25,978
Pampacancha delivery obligation [Member]
Revenue And Expenses [Line Items]
Other operating expenses	0	7,499
Other [Member]
Revenue And Expenses [Line Items]
Other operating expenses	$ 3,292	$ 4,547

Revenue and expenses (Schedul_5

Revenue and expenses (Schedule of detailed information about impairment) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Revenue And Expenses [Line Items]
Asset impairment loss	$ 0	$ 322,249
Arizona [Member]
Revenue And Expenses [Line Items]
Asset impairment loss		322,249
Tax impact - (recovery)		(80,143)
After-tax impairment charge		$ 242,106

Revenue and expenses (Schedul_6

Revenue and expenses (Schedule of detailed information about employee benefits expense) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Revenue And Expenses [Line Items]
Current employee benefits	$ 179,486	$ 171,173
Share-based payments	15,008	2,714
Employee share purchase plan	1,783	1,645
Defined benefit plans	11,671	10,643
Defined contribution plans	1,774	1,635
Other post-retirement employee benefits	9,305	8,457
Termination benefits	582	628
Employee benefits expense	219,609	196,895
Stock Options [Member]
Revenue And Expenses [Line Items]
Share-based payments	1,122	0
Restricted Share Unit [Member]
Revenue And Expenses [Line Items]
Share-based payments	6,750	1,557
Deferred Share Unit [Member]
Revenue And Expenses [Line Items]
Share-based payments	5,149	1,157
Performance Share Unit [Member]
Revenue And Expenses [Line Items]
Share-based payments	$ 1,987	$ 0

Revenue and expenses (Schedul_7

Revenue and expenses (Schedule of Finance income and expenses) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Net interest expense on long-term debt
Interest expense on long-term debt	$ 82,712	$ 78,265
Interest capitalized	0	(9,890)
Net interest expense on long-term debt	82,712	68,375
Accretion on streaming arrangements
Current year additions	60,362	63,725
Variable consideration adjustments - prior periods	(3,692)	6,047
Accretion on streaming arrangements	56,670	69,772
Change in fair value of financial assets and liabilities at fair value through profit or loss
Embedded derivatives	(45,387)	3,708
Gold prepayment liability	20,141	0
Investments	(4,124)	4,539
Change in fair value of financial assets and liabilities at fair value through profit or loss	(29,370)	8,247
Other net finance costs
Net foreign exchange (gains) losses	(1,644)	1,388
Accretion on community agreements measured at amortized cost	3,641	1,222
Unwinding of discounts on provisions	3,543	4,392
Withholding taxes	8,267	8,100
Premium paid on redemption of notes	7,252	0
Write-down of unamortized transaction costs	3,817	0
Other finance expense	8,826	11,027
Interest income	(1,812)	(8,527)
Other net finance costs	31,890	17,602
Net finance expense	$ 141,902	$ 163,996

Trade and other receivables (Sc

Trade and other receivables (Schedule of detailed information about trade and other receivables explanatory) (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Current
Trade receivables	$ 107,787	$ 87,332
Statutory receivables	28,445	16,543
Other receivables	4,967	2,119
Total current trade and other receivables	141,199	105,994
Non-current
Taxes receivable	16,941	17,669
Other receivables	1,627	1,595
Trade and other non-current receivables	18,568	19,264
Trade and other receivables	$ 159,767	$ 125,258

Inventories (Schedule of detail

Inventories (Schedule of detailed information about inventories) (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Current
Stockpile	$ 13,906	$ 10,396
Work in progress	6,364	14,420
Finished goods	72,923	62,230
Materials and supplies	49,912	51,774
Current Inventories	143,105	138,820
Non-current
Stockpile	16,704	14,626
Materials and supplies	5,302	4,829
Non current Inventories	22,006	19,455
Total Inventories	$ 165,111	$ 158,275

Other financial assets (Schedul

Other financial assets (Schedule of other financial assets) (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Current
Derivative assets	$ 2,736	$ 1,712
Restricted cash	337	337
Other current financial assets	3,073	2,049
Non-current
Investments at fair value through profit or loss	15,669	11,287
Total other financial assets	$ 18,742	$ 13,336

Intangibles and other assets (S

Intangibles and other assets (Schedule of detailed information about intangible assets) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Disclosure of reconciliation of changes in intangible assets [line items]
Balance, beginning of year	$ 5,027
Balance, end of year	5,409	$ 5,027
Cost [Member]
Disclosure of reconciliation of changes in intangible assets [line items]
Balance, beginning of year	21,538	18,557
Additions	1,466	2,325
Disposals	0	(96)
Effects of movement in exchange rates	346	752
Balance, end of year	23,350	21,538
Accumulated amortization [Member]
Disclosure of reconciliation of changes in intangible assets [line items]
Balance, beginning of year	16,511	14,395
Additions	1,138	1,606
Disposals	0	(96)
Effects of movement in exchange rates	292	606
Balance, end of year	$ 17,941	$ 16,511

Property, plant and equipment_3

Property, plant and equipment (Schedule of detailed information about property, plant and equipment) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Disclosure of detailed information about property, plant and equipment [line items]
Balance, beginning of year	$ 3,662,559
Additions	17,759	$ 22,158
Decommissioning and restoration	46,792	89,408
Interest capitalized	0	9,890
Impairments		(322,249)
Balance, end of year	3,731,655	3,662,559
Cost [Member]
Disclosure of detailed information about property, plant and equipment [line items]
Balance, beginning of year	5,806,084	5,577,753
Additions	303,653	181,855
Acquisitions		94,862
Capitalized stripping and development	83,137	103,108
Decommissioning and restoration	46,792	89,408
Interest capitalized	0	9,890
Transfers and other movements	0	0
Impairments		(322,249)
Disposals	(25,565)	(14,309)
Effects of movement in exchange rates	47,603	83,534
Other		2,232
Balance, end of year	6,261,704	5,806,084
Accumulated depreciation [Member]
Disclosure of detailed information about property, plant and equipment [line items]
Balance, beginning of year	2,143,525	1,742,961
Depreciation for the year	370,096	353,882
Disposals	(16,513)	(6,675)
Effects of movement in exchange rates	32,941	53,357
Balance, end of year	2,530,049	2,143,525
Exploration and evaluation assets [Member]
Disclosure of detailed information about property, plant and equipment [line items]
Balance, beginning of year	69,903
Balance, end of year	79,059	69,903
Exploration and evaluation assets [Member] \| Cost [Member]
Disclosure of detailed information about property, plant and equipment [line items]
Balance, beginning of year	69,903	52,206
Additions	809	17,016
Acquisitions		0
Capitalized stripping and development	0	0
Decommissioning and restoration	0	0
Interest capitalized	0	0
Transfers and other movements	8,040	0
Impairments		0
Disposals	0	0
Effects of movement in exchange rates	307	681
Other		0
Balance, end of year	79,059	69,903
Exploration and evaluation assets [Member] \| Accumulated depreciation [Member]
Disclosure of detailed information about property, plant and equipment [line items]
Balance, beginning of year	0	0
Depreciation for the year	0	0
Disposals	0	0
Effects of movement in exchange rates	0	0
Balance, end of year	0	0
Capital works in progress [Member]
Disclosure of detailed information about property, plant and equipment [line items]
Balance, beginning of year	733,874
Balance, end of year	957,162	733,874
Capital works in progress [Member] \| Cost [Member]
Disclosure of detailed information about property, plant and equipment [line items]
Balance, beginning of year	733,874	873,781
Additions	256,251	109,372
Acquisitions		91,332
Capitalized stripping and development	0	0
Decommissioning and restoration	263	41
Interest capitalized	0	9,890
Transfers and other movements	(36,668)	(30,000)
Impairments		(322,249)
Disposals	0	(2,029)
Effects of movement in exchange rates	3,442	1,528
Other		2,208
Balance, end of year	957,162	733,874
Capital works in progress [Member] \| Accumulated depreciation [Member]
Disclosure of detailed information about property, plant and equipment [line items]
Balance, beginning of year	0	0
Depreciation for the year	0	0
Disposals	0	0
Effects of movement in exchange rates	0	0
Balance, end of year	0	0
Mining properties [Member]
Disclosure of detailed information about property, plant and equipment [line items]
Balance, beginning of year	1,183,053
Balance, end of year	1,091,187	1,183,053
Mining properties [Member] \| Cost [Member]
Disclosure of detailed information about property, plant and equipment [line items]
Balance, beginning of year	2,146,583	1,998,439
Additions	311	0
Acquisitions		3,157
Capitalized stripping and development	83,137	103,108
Decommissioning and restoration	6,849	3,314
Interest capitalized	0	0
Transfers and other movements	(41,256)	642
Impairments		0
Disposals	0	0
Effects of movement in exchange rates	21,837	41,080
Other		(3,157)
Balance, end of year	2,217,461	2,146,583
Mining properties [Member] \| Accumulated depreciation [Member]
Disclosure of detailed information about property, plant and equipment [line items]
Balance, beginning of year	963,530	780,754
Depreciation for the year	146,113	154,970
Disposals	0	0
Effects of movement in exchange rates	16,631	27,806
Balance, end of year	1,126,274	963,530
Plant and equipment [Member]
Disclosure of detailed information about property, plant and equipment [line items]
Balance, beginning of year	1,584,065
Balance, end of year	1,522,138	1,584,065
Plant and equipment [Member] \| Cost [Member]
Disclosure of detailed information about property, plant and equipment [line items]
Balance, beginning of year	2,653,752	2,473,176
Additions	28,523	33,309
Acquisitions		0
Capitalized stripping and development	0	0
Decommissioning and restoration	39,680	86,053
Interest capitalized	0	0
Transfers and other movements	70,777	30,406
Impairments		0
Disposals	(19,681)	(10,747)
Effects of movement in exchange rates	20,668	38,452
Other		3,103
Balance, end of year	2,793,719	2,653,752
Plant and equipment [Member] \| Accumulated depreciation [Member]
Disclosure of detailed information about property, plant and equipment [line items]
Balance, beginning of year	1,069,687	872,330
Depreciation for the year	200,632	179,062
Disposals	(14,038)	(6,675)
Effects of movement in exchange rates	15,300	24,970
Balance, end of year	1,271,581	1,069,687
Plant and equipment- ROU assets [Member]
Disclosure of detailed information about property, plant and equipment [line items]
Balance, beginning of year	91,664
Balance, end of year	82,109	91,664
Plant and equipment- ROU assets [Member] \| Cost [Member]
Disclosure of detailed information about property, plant and equipment [line items]
Balance, beginning of year	201,972	180,151
Additions	17,759	22,158
Acquisitions		373
Capitalized stripping and development	0	0
Decommissioning and restoration	0	0
Interest capitalized	0	0
Transfers and other movements	(893)	(1,048)
Impairments		0
Disposals	(5,884)	(1,533)
Effects of movement in exchange rates	1,349	1,793
Other		78
Balance, end of year	214,303	201,972
Plant and equipment- ROU assets [Member] \| Accumulated depreciation [Member]
Disclosure of detailed information about property, plant and equipment [line items]
Balance, beginning of year	110,308	89,877
Depreciation for the year	23,351	19,850
Disposals	(2,475)	0
Effects of movement in exchange rates	1,010	581
Balance, end of year	$ 132,194	$ 110,308

Trade and other payables (Sched

Trade and other payables (Schedule of detailed information about trade and other payables) (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Trade and other payables [abstract]
Trade payables	$ 104,598	$ 68,742
Accruals and payables	72,698	80,375
Accrued interest	30,766	34,603
Exploration and evaluation payables	1,351	884
Statutory payables	23,734	7,800
Trade and other payables	$ 233,147	$ 192,404

Other liabilities (Schedule of

Other liabilities (Schedule of other current liabilities) (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Current
Provisions	$ 33,675	$ 33,575
Pension liability	13,552	12,015
Other employee benefits	3,154	2,806
Unearned revenue	1,590	1,015
Other liabilities	$ 51,971	$ 49,411

Other financial liabilities (Sc

Other financial liabilities (Schedule of detailed information about other financial liabilities) (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Current
Derivative liabilities	$ 15,312	$ 10,295
Embedded derivatives	0	9,074
Other financial liabilities at amortized cost	9,401	8,707
Other financial liabilities, current	24,713	28,076
Non-current
Deferred Rosemont acquisition consideration	25,961	24,491
Gold prepayment liability	137,031	0
Other financial liabilities at amortized cost	31,386	15,293
Other financial liabilities, non-current	194,378	39,784
Other financial liabilities	$ 219,091	$ 67,860

Other financial liabilities (_2

Other financial liabilities (Schedule of detailed information about changes in other financial liabilities at amortized cost) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Disclosure of financial liabilities [abstract]
Beginning balance	$ 24,000	$ 21,361
Net additions	116,233	7,369
Disbursements	(98,375)	(6,351)
Accretion	3,641	1,222
Effects of changes in foreign exchange	(4,712)	399
Ending balance	$ 40,787	$ 24,000

Lease Liability (Schedule of ad

Lease Liability (Schedule of additional information about leasing activities for lessee) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2020	Dec. 31, 2019
Lease liabilities [abstract]
Beginning balance	$ 81,947	$ 89,215
Additional capitalized leases	17,759	22,158
Lease payments	(35,980)	(32,952)
Accretion and other movements	(212)	3,526
Ending balance	63,514	81,947
Current lease liabilities			$ 33,473	$ 32,781
Non-current lease liabilities			30,041	49,166
Lease Liabilities	$ 63,514	$ 81,947	$ 63,514	$ 81,947

Lease Liability (Schedule of ex

Lease Liability (Schedule of expenses recognized to leases for which exemption applied) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Lease liabilities [abstract]
Short-term leases	$ 40,253	$ 45,745
Low value leases	353	92
Variable leases	57,389	56,152
Total	$ 97,995	$ 101,989

Long-term debt (Schedule of bor

Long-term debt (Schedule of borrowings) (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Disclosure of detailed information about borrowings [line items]
Total debt	$ 1,135,675	$ 985,255
Senior unsecured notes [Member]
Disclosure of detailed information about borrowings [line items]
Total debt	1,139,695	991,558	$ 989,306
Unamortized transaction costs - revolving credit facilities [Member]
Disclosure of detailed information about borrowings [line items]
Less: Unamortized transaction costs - revolving credit facilities	$ (4,020)	$ (6,303)	$ (8,276)

Long-term debt (Schedule of det

Long-term debt (Schedule of detailed information about borrowings) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Disclosure of detailed information about borrowings [line items]
Borrowings, beginning balance	$ 985,255
Addition to Principal	591,824
Principal repayments	(400,000)
Transaction costs	16,204	$ 26,149
Write-down of unamortized transaction costs	3,817	0
Borrowings, ending balance	1,135,675	985,255
Senior unsecured notes [Member]
Disclosure of detailed information about borrowings [line items]
Borrowings, beginning balance	991,558	989,306
Addition to Principal	591,824
Principal repayments	(400,000)
Transaction costs	8,176
Change in fair value of embedded derivative (prepayment option)	(47,169)	1,079
Write-down of unamortized transaction costs	2,315
Accretion of transaction costs and premiums	1,167	1,173
Borrowings, ending balance	$ 1,139,695	$ 991,558

Long-term debt (Schedule of d_2

Long-term debt (Schedule of detailed information about unamortized transaction costs - revolving credit facilities) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Disclosure of detailed information about borrowings [line items]
Write-down of unamortized transaction costs	$ (3,817)	$ 0
Unamortized transaction costs - revolving credit facilities [Member]
Disclosure of detailed information about borrowings [line items]
Unamortized transaction costs, beginning balance	6,303	8,276
Accretion of transaction costs	(3,062)	(2,342)
Write-down of unamortized transaction costs	(1,502)
Transaction costs	2,281	369
Unamortized transaction costs, ending balance	$ 4,020	$ 6,303

Deferred revenue (Schedule of c

Deferred revenue (Schedule of changes in deferred revenue) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Disclosure Of Deferred Revenue [Abstract]
Stream accounting - Deferred revenue, beginning balance	$ 563,756	$ 566,078
Amortization of deferred revenue
Liability drawdown	(67,263)	(92,398)
Variable consideration adjustments - prior periods	(6,668)	16,295
Accretion on streaming arrangements
Current year additions	60,362	63,725
Variable consideration adjustments - prior periods	(3,692)	6,047
Effects of changes in foreign exchange	189	4,009
Stream accounting - Deferred revenue, ending balance	$ 546,684	$ 563,756

Deferred revenue (Schedule of d

Deferred revenue (Schedule of detailed information about deferred revenue) (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Disclosure Of Deferred Revenue [Abstract]
Current	$ 102,782	$ 86,933
Non-current	443,902	476,823
Deferred revenue	$ 546,684	$ 563,756	$ 566,078

Provisions (Schedule of changes

Provisions (Schedule of changes in provisions) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Disclosure of other provisions [line items]
Provisions, beginning balance	$ 314,425	$ 218,924
Net additional provisions made	12,410	76,127
Amounts used	(23,704)	(15,525)
Unwinding of discount	3,543	4,392
Effect of change in discount rate	43,180	23,635
Effect of foreign exchange	7,509	7,648
Effect of change in share price	8,111	(776)
Provisions, ending balance	365,474	314,425
Decommissioning, restoration and similar liabilities [Member]
Disclosure of other provisions [line items]
Provisions, beginning balance	302,116	202,024
Net additional provisions made	5,868	68,881
Amounts used	(18,737)	(4,136)
Unwinding of discount	3,543	4,392
Effect of change in discount rate	43,180	23,635
Effect of foreign exchange	7,162	7,320
Effect of change in share price	0	0
Provisions, ending balance	343,132	302,116
Deferred share units [Member]
Disclosure of other provisions [line items]
Provisions, beginning balance	3,876	4,288
Net additional provisions made	1,628	1,479
Amounts used	(497)	(1,668)
Unwinding of discount	0	0
Effect of change in discount rate	0	0
Effect of foreign exchange	191	99
Effect of change in share price	3,521	(322)
Provisions, ending balance	8,719	3,876
Restricted share units [Member]
Disclosure of other provisions [line items]
Provisions, beginning balance	5,477	12,201
Net additional provisions made	3,642	2,885
Amounts used	(2,646)	(9,380)
Unwinding of discount	0	0
Effect of change in discount rate	0	0
Effect of foreign exchange	116	225
Effect of change in share price	3,860	(454)
Provisions, ending balance	10,449	5,477
Performance share unit [Member]
Disclosure of other provisions [line items]
Provisions, beginning balance	0	0
Net additional provisions made	1,257	0
Amounts used	0	0
Unwinding of discount	0	0
Effect of change in discount rate	0	0
Effect of foreign exchange	43	0
Effect of change in share price	730	0
Provisions, ending balance	2,030	0
Other provisions [Member]
Disclosure of other provisions [line items]
Provisions, beginning balance	2,956	411
Net additional provisions made	15	2,882
Amounts used	(1,824)	(341)
Unwinding of discount	0	0
Effect of change in discount rate	0	0
Effect of foreign exchange	(3)	4
Effect of change in share price	0	0
Provisions, ending balance	$ 1,144	$ 2,956

Provisions (Schedule of detaile

Provisions (Schedule of detailed information about provisions) (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Disclosure of other provisions [line items]
Current provisions	$ 33,675	$ 33,575
Non-current provisions	331,799	280,850
Total provisions	365,474	314,425	$ 218,924
Decommissioning, restoration and similar liabilities [Member]
Disclosure of other provisions [line items]
Current provisions	20,308	23,621
Non-current provisions	322,824	278,495
Total provisions	343,132	302,116	202,024
Deferred share units [Member]
Disclosure of other provisions [line items]
Current provisions	8,719	3,876
Non-current provisions	0	0
Total provisions	8,719	3,876	4,288
Restricted share units [Member]
Disclosure of other provisions [line items]
Current provisions	4,648	4,468
Non-current provisions	5,801	1,009
Total provisions	10,449	5,477	12,201
Performance share unit [Member]
Disclosure of other provisions [line items]
Current provisions	0	0
Non-current provisions	2,030
Total provisions	2,030	0	0
Other provisions [Member]
Disclosure of other provisions [line items]
Current provisions	0	1,610
Non-current provisions	1,144	1,346
Total provisions	$ 1,144	$ 2,956	$ 411

Pension obligations (Schedule o

Pension obligations (Schedule of additional information about defined benefit plans) - (Details) - Pension obligations [Member] - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Pension Obligations [Line Items]
Opening defined benefit obligation	$ 243,733	$ 211,512
Current service cost	11,044	9,880
Interest cost	6,569	7,156
Benefits paid from plan	(35,384)	(16,745)
Benefits paid from employer	(1,317)	(934)
Participant contributions	48	64
Effects of movements in exchange rates	2,780	11,660
Arising from changes in demographic assumptions	(1,461)	0
Arising from changes in financial assumptions	16,967	29,609
Arising from experience adjustments	(2,625)	(2,258)
Settlement payments from plan assets	0	(6,307)
Loss on settlement	0	96
Closing defined benefit obligation	$ 240,354	$ 243,733

Pension obligations (Schedule_2

Pension obligations (Schedule of additional information about defined benefit plans, balance by member group) - (Details) - Pension obligations [Member] - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Pension Obligations [Line Items]
Closing defined benefit obligation	$ 240,354	$ 243,733	$ 211,512
Active members [Member]
Pension Obligations [Line Items]
Closing defined benefit obligation	211,861	231,959
Deferred members [Member]
Pension Obligations [Line Items]
Closing defined benefit obligation	2,198	1,555
Retired members [Member]
Pension Obligations [Line Items]
Closing defined benefit obligation	$ 26,295	$ 10,219

Pension obligations (Schedule_3

Pension obligations (Schedule of changes in fair value of plan assets) - (Details) - Pension obligations [Member] - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Pension Obligations [Line Items]
Opening fair value of plan assets	$ 202,119	$ 175,795
Interest income	5,695	6,170
Return on plan assets (excluding amounts included in net interest expense)	15,377	21,460
Contributions from the employer	12,987	11,952
Employer direct benefit payments	1,317	934
Contributions from plan participants	48	64
Benefit payment from employer	(1,317)	(934)
Administrative expenses paid from plan assets	(77)	(82)
Benefits paid	(35,384)	(16,745)
Settlement payments from plan assets	0	(6,307)
Effects of changes in foreign exchange rates	2,721	9,812
Closing fair value of plan assets	$ 203,486	$ 202,119

Pension obligations (Schedule_4

Pension obligations (Schedule of net defined benefit liability (asset)) - (Details) - Pension obligations [Member] - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Pension Obligations [Line Items]
Present value of funded defined benefit obligation	$ 220,210	$ 224,364
Fair value of plan assets	(203,486)	(202,119)	$ (175,795)
Present value of unfunded defined benefit obligation	20,144	19,369
Net liability arising from defined benefit obligation	$ 36,868	$ 41,614

Pension obligations (Schedule_5

Pension obligations (Schedule of detailed information about pension obligation) - (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Pension Obligations [Line Items]
Pension obligation - non-current	$ 23,316	$ 29,599
Pension obligations [Member]
Pension Obligations [Line Items]
Pension obligation - current	13,552	12,015
Pension obligation - non-current	23,316	29,599
Net liability	$ 36,868	$ 41,614

Pension obligations (Schedule_6

Pension obligations (Schedule of detailed information about pension expense) - (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Pension Obligations [Line Items]
Defined benefit pension expense	$ 11,671	$ 10,643
Defined contribution pension expense	1,774	1,635
Pension obligations [Member]
Pension Obligations [Line Items]
Current service cost	11,044	9,880
Loss on settlement	0	96
Total service cost	11,044	9,976
Net interest expense	874	986
Administration cost	77	82
Defined benefit pension expense	11,995	11,044
Defined contribution pension expense	$ 1,791	$ 1,639

Pension obligations (Schedule_7

Pension obligations (Schedule of detailed information about remeasurement on net defined benefit liability) - (Details) - Pension obligations [Member] - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Pension Obligations [Line Items]
Return on plan assets (excluding amounts included in net interest expense)	$ (15,377)	$ (21,460)
Actuarial gains arising from changes in demographic assumptions	(1,461)	0
Actuarial losses arising from changes in financial assumptions	16,967	29,609
Actuarial (gains)/losses arising from changes experience adjustments	(2,625)	(2,258)
Components recognized in statements of comprehensive income	(2,496)	5,891
Total pension cost	$ 11,290	$ 18,574

Pension obligations (Schedule_8

Pension obligations (Schedule of defined benefit plan, assumptions used) - (Details) - Pension obligations [Member] - USD ($)	Dec. 31, 2020	Dec. 31, 2019
Defined benefit cost [Member]
Pension Obligations [Line Items]
Expected rate of salary increase	2.75%	2.75%
Defined benefit cost [Member] \| Benefit obligations [Member]
Pension Obligations [Line Items]
Discount rate	3.08%	3.73%
Defined benefit cost [Member] \| Service cost [Member]
Pension Obligations [Line Items]
Discount rate	3.10%	3.75%
Defined benefit cost [Member] \| Males [Member]
Pension Obligations [Line Items]
Average longevity at retirement age for current pensioners (years)	21.2	21.1
Defined benefit cost [Member] \| Females [Member]
Pension Obligations [Line Items]
Average longevity at retirement age for current pensioners (years)	23.9	23.9
Defined benefit obligation [Member]
Pension Obligations [Line Items]
Discount rate	2.54%	3.08%
Expected rate of salary increase	2.75%	2.75%
Defined benefit obligation [Member] \| Males [Member]
Pension Obligations [Line Items]
Average longevity at retirement age for current pensioners (years)	20.3	21.2
Average longevity at retirement age for current employees (future pensioners) (years)	22.2	23
Defined benefit obligation [Member] \| Females [Member]
Pension Obligations [Line Items]
Average longevity at retirement age for current pensioners (years)	23.7	23.9
Average longevity at retirement age for current employees (future pensioners) (years)	25.4	25.6

Pension obligations (Schedule_9

Pension obligations (Schedule of fair value of plan assets) - (Details) - Pension obligations [Member] - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Pension Obligations [Line Items]
Plan assets, at fair value	$ 203,486	$ 202,119	$ 175,795
Level 1 [Member]
Pension Obligations [Line Items]
Plan assets, at fair value	73,692	78,268
Level 2 [Member]
Pension Obligations [Line Items]
Plan assets, at fair value	129,794	123,851
Level 3 [Member]
Pension Obligations [Line Items]
Plan assets, at fair value	0	0
Money market instruments [Member]
Pension Obligations [Line Items]
Cash and cash equivalents, amount contributed to fair value of plan assets	4,766	1,588
Money market instruments [Member] \| Level 1 [Member]
Pension Obligations [Line Items]
Cash and cash equivalents, amount contributed to fair value of plan assets	4,766	1,588
Money market instruments [Member] \| Level 2 [Member]
Pension Obligations [Line Items]
Cash and cash equivalents, amount contributed to fair value of plan assets	0	0
Money market instruments [Member] \| Level 3 [Member]
Pension Obligations [Line Items]
Cash and cash equivalents, amount contributed to fair value of plan assets	0	0
Pooled equity funds [Member]
Pension Obligations [Line Items]
Investment funds, amount contributed to fair value of plan assets	68,926	76,680
Pooled equity funds [Member] \| Level 1 [Member]
Pension Obligations [Line Items]
Investment funds, amount contributed to fair value of plan assets	68,926	76,680
Pooled equity funds [Member] \| Level 2 [Member]
Pension Obligations [Line Items]
Investment funds, amount contributed to fair value of plan assets	0	0
Pooled equity funds [Member] \| Level 3 [Member]
Pension Obligations [Line Items]
Investment funds, amount contributed to fair value of plan assets	0	0
Pooled fixed income funds [Member]
Pension Obligations [Line Items]
Investment funds, amount contributed to fair value of plan assets	98,922	103,646
Pooled fixed income funds [Member] \| Level 1 [Member]
Pension Obligations [Line Items]
Investment funds, amount contributed to fair value of plan assets	0	0
Pooled fixed income funds [Member] \| Level 2 [Member]
Pension Obligations [Line Items]
Investment funds, amount contributed to fair value of plan assets	98,922	103,646
Pooled fixed income funds [Member] \| Level 3 [Member]
Pension Obligations [Line Items]
Investment funds, amount contributed to fair value of plan assets	0	0
Alternative investment funds [Member]
Pension Obligations [Line Items]
Investment funds, amount contributed to fair value of plan assets	30,323	19,438
Alternative investment funds [Member] \| Level 1 [Member]
Pension Obligations [Line Items]
Investment funds, amount contributed to fair value of plan assets	0	0
Alternative investment funds [Member] \| Level 2 [Member]
Pension Obligations [Line Items]
Investment funds, amount contributed to fair value of plan assets	30,323	19,438
Alternative investment funds [Member] \| Level 3 [Member]
Pension Obligations [Line Items]
Investment funds, amount contributed to fair value of plan assets	0	0
Balanced Fund [Member]
Pension Obligations [Line Items]
Investment funds, amount contributed to fair value of plan assets	549	767
Balanced Fund [Member] \| Level 1 [Member]
Pension Obligations [Line Items]
Investment funds, amount contributed to fair value of plan assets	0	0
Balanced Fund [Member] \| Level 2 [Member]
Pension Obligations [Line Items]
Investment funds, amount contributed to fair value of plan assets	549	767
Balanced Fund [Member] \| Level 3 [Member]
Pension Obligations [Line Items]
Investment funds, amount contributed to fair value of plan assets	$ 0	$ 0

Other employee benefits (Schedu

Other employee benefits (Schedule of additional information about other employee benefit plans) - (Details) - Other employee benefits [Member] - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Other Employee Benefits [Line Items]
Opening defined benefit obligation	$ 116,696	$ 93,528
Current service cost	4,140	3,060
Past service cost	0	0
Interest cost	3,478	3,600
Effects of movements in exchange rates	2,423	4,864
Remeasurement actuarial (gains)/losses:
Arising from changes in demographic assumptions	(4,460)	0
Arising from changes in financial assumptions	10,043	14,094
Arising from experience adjustments	(489)	87
Benefits paid	(2,215)	(2,537)
Closing defined benefit obligation	$ 129,616	$ 116,696

Other employee benefits (Sche_2

Other employee benefits (Schedule of additional information about other employee benefit plans, balance by member group) - (Details) - Other employee benefits [Member] - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Other Employee Benefits [Line Items]
Closing defined benefit obligation	$ 129,616	$ 116,696	$ 93,528
Active members [Member]
Other Employee Benefits [Line Items]
Closing defined benefit obligation	68,983	60,801
Inactive members [Member]
Other Employee Benefits [Line Items]
Closing defined benefit obligation	$ 60,633	$ 55,895

Other employee benefits (Sche_3

Other employee benefits (Schedule of changes in fair value of assets of other employee benefits plan) (Details) - Other employee benefits [Member] - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Other Employee Benefits [Line Items]
Employer contributions	$ 2,215	$ 2,537
Benefits paid	(2,215)	(2,537)
Closing fair value of assets	$ 0	$ 0

Other employee benefits (Sche_4

Other employee benefits (Schedule of net benefit liability for other employee benefits (Details) - Other employee benefits [Member] - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Other Employee Benefits [Line Items]
Unfunded benefit obligation	$ 129,616	$ 116,696	$ 93,528
Vacation accrual and other - non-current	3,046	2,888
Net liability	$ 132,662	$ 119,584

Other employee benefits (Sche_5

Other employee benefits (Schedule of detailed information about other employee benefits plan) (Details) - Other employee benefits [Member] - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Other Employee Benefits [Line Items]
Other employee benefits liability - current	$ 3,154	$ 2,806
Other employee benefits liability - non-current	129,508	116,778
Net liability	$ 132,662	$ 119,584

Other employee benefits (Sche_6

Other employee benefits (Schedule of detailed information about employee future benefit expense) (Details) - Other employee benefits [Member] - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Other Employee Benefits [Line Items]
Current service cost	$ 4,140	$ 3,060
Net interest expense	3,478	3,600
Components recognized in consolidated income statements	$ 7,618	$ 6,660

Other employee benefits (Sche_7

Other employee benefits (Schedule of detailed information about remeasurement of other long term employee benefits) (Details) - Other employee benefits [Member] - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Other Employee Benefits [Line Items]
Actuarial gains arising from changes in demographic assumptions	$ (4,460)	$ 0
Actuarial losses arising from changes in financial assumptions	10,043	14,094
Actuarial (gains)/losses arising from changes experience adjustments	(489)	87
Components recognized in statements of comprehensive income	5,094	14,181
Total other employee future benefit cost	$ 12,712	$ 20,841

Other employee benefits (Sche_8

Other employee benefits (Schedule of other employee benefit plan, assumptions used (Details) - Other employee benefits [Member] - USD ($)	Dec. 31, 2020	Dec. 31, 2019
Defined benefit cost [Member]
Other Employee Benefits [Line Items]
Discount rate	3.17%	3.88%
Defined benefit cost [Member] \| Initial [Member]
Other Employee Benefits [Line Items]
Weighted average health care trend rate	5.68%	5.74%
Defined benefit cost [Member] \| Ultimate [Member]
Other Employee Benefits [Line Items]
Weighted average health care trend rate	4.00%	4.00%
Defined benefit cost [Member] \| Males [Member]
Other Employee Benefits [Line Items]
Average longevity at retirement age for current pensioners (years)	21.2	21.1
Defined benefit cost [Member] \| Females [Member]
Other Employee Benefits [Line Items]
Average longevity at retirement age for current pensioners (years)	23.9	23.9
Defined benefit obligation [Member]
Other Employee Benefits [Line Items]
Discount rate	2.76%	3.17%
Defined benefit obligation [Member] \| Initial [Member]
Other Employee Benefits [Line Items]
Weighted average health care trend rate	5.66%	5.68%
Defined benefit obligation [Member] \| Ultimate [Member]
Other Employee Benefits [Line Items]
Weighted average health care trend rate	4.00%	4.00%
Defined benefit obligation [Member] \| Males [Member]
Other Employee Benefits [Line Items]
Average longevity at retirement age for current pensioners (years)	20.3	21.2
Average longevity at retirement age for current employees (future pensioners) (years)	22.2	23.1
Defined benefit obligation [Member] \| Females [Member]
Other Employee Benefits [Line Items]
Average longevity at retirement age for current pensioners (years)	23.7	23.9
Average longevity at retirement age for current employees (future pensioners) (years)	25.4	25.6

Income and mining taxes (Schedu

Income and mining taxes (Schedule of detailed information about effective income tax expense recovery) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Major components of tax expense (income) [abstract]
Current income tax expense	$ 4,458	$ 24,919
Mining taxes	4,671	4,720
Adjustments in respect of prior years	(398)	6,273
Current tax expense (income) and adjustments for current tax of prior periods	8,731	35,912
Income tax recoveries - origination, revaluation and/or reversal of temporary differences	(39,411)	(133,468)
Mining tax recoveries - origination, revaluation and/or reversal of temporary difference	(3,331)	(12,214)
Adjustments in respect of prior years	(494)	817
Deferred tax expense (income)	(43,236)	(144,865)
Tax recovery	$ (34,505)	$ (108,953)

Income and mining taxes (Sche_2

Income and mining taxes (Schedule of deferred taxes) (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Disclosure of temporary difference, unused tax losses and unused tax credits [line items]
Deferred income tax asset	$ 101,899	$ 75,046
Deferred income tax liability	(229,433)	(242,928)
Net deferred tax asset (liability)	(127,534)	(167,882)	$ (308,577)
Income tax effect of temporary differences [Member]
Disclosure of temporary difference, unused tax losses and unused tax credits [line items]
Deferred income tax asset	94,070	69,950
Deferred income tax liability	(220,568)	(233,218)
Net deferred tax asset (liability)	(126,498)	(163,268)
Mining tax effect of temporary differences recognized [Member]
Disclosure of temporary difference, unused tax losses and unused tax credits [line items]
Deferred income tax asset	7,829	5,096
Deferred income tax liability	$ (8,865)	$ (9,710)

Income and mining taxes (Sche_3

Income and mining taxes (Schedule of changes in deferred tax assets and liabilities) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Major components of tax expense (income) [abstract]
Net deferred tax liability balance, beginning of year	$ (167,882)	$ (308,577)
Deferred tax recovery	43,236	144,865
OCI transactions	(759)	1,878
Foreign currency translation on the deferred tax liability	(2,129)	(6,048)
Net deferred tax liability balance, end of year	$ (127,534)	$ (167,882)

Income and mining taxes (Sche_4

Income and mining taxes (Schedule of reconciliation to statutory tax rate) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Major components of tax expense (income) [abstract]
Statutory tax rate	26.30%	27.00%
Tax expense at statutory rate	$ (47,047)	$ (122,246)
Effect of Deductions related to mining taxes	(1,369)	(1,493)
Adjusted income taxes	(48,416)	(123,739)
Mining tax expense (recovery)	1,291	(6,674)
Adjusted income tax expense after mining tax expense (recovery)	(47,125)	(130,413)
Permanent differences related to capital items	(160)	3,270
Permanent differences related to other income tax permanent differences	(1,165)	1,747
Impact of remeasurement on decommissioning liability	7,094	(12,018)
Temporary income tax differences not recognized	(1,827)	(351)
Other temporary income tax differences not recognized	2,927	2,323
Non-deductible impairment on UCM receivable	0	7,041
Withholding tax on dividends	0	6,826
Impact related to differences in tax rates in foreign operations	5,534	20,338
Impact of changes to statutory tax rates	2,412	(259)
Foreign exchange on non-monetary items	(3,628)	(6,633)
Impact related to tax assessments and tax return amendments	1,433	(824)
Tax recovery	$ (34,505)	$ (108,953)

Income and mining taxes (Sche_5

Income and mining taxes (Schedule of temporary differences recognized) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Disclosure of temporary difference, unused tax losses and unused tax credits [line items]
Deferred income tax (liability) asset	$ (127,534)	$ (167,882)	$ (308,577)
Property, plant and equipment [Member]
Disclosure of temporary difference, unused tax losses and unused tax credits [line items]
Deferred income tax asset	(88,368)	(96,841)
Deferred income tax (recovery) expense	(8,473)	13,434
Deferred income tax liability	292,858	259,145
Deferred income tax expense (recovery)	33,713	(79,892)
Pension obligation [Member]
Disclosure of temporary difference, unused tax losses and unused tax credits [line items]
Deferred income tax asset	9,467	11,332
Deferred income tax (recovery) expense	1,294	(1,115)
Other employee benefits [Member]
Disclosure of temporary difference, unused tax losses and unused tax credits [line items]
Deferred income tax asset	25,687	16,837
Deferred income tax (recovery) expense	(8,850)	3,349
Deferred income tax liability	203	(80)
Deferred income tax expense (recovery)	(176)	(320)
Decommissioning and restoration obligation [Member]
Disclosure of temporary difference, unused tax losses and unused tax credits [line items]
Deferred income tax asset	37,902	41,208
Deferred income tax (recovery) expense	3,307	(33,391)
Asset retirement obligations [Member]
Disclosure of temporary difference, unused tax losses and unused tax credits [line items]
Deferred income tax liability	(1,588)	(833)
Deferred income tax expense (recovery)	(756)	85
Non-capital losses [Member]
Disclosure of temporary difference, unused tax losses and unused tax credits [line items]
Deferred income tax asset	110,374	90,446
Deferred income tax (recovery) expense	(19,928)	(17,976)
Deferred income tax liability	(78,607)	(28,643)
Deferred income tax expense (recovery)	(49,965)	(1,269)
Share issue and debt costs [Member]
Disclosure of temporary difference, unused tax losses and unused tax credits [line items]
Deferred income tax asset	8,972	6,540
Deferred income tax (recovery) expense	(2,768)	4,361
Embedded derivative (prepayment option) [Member]
Disclosure of temporary difference, unused tax losses and unused tax credits [line items]
Deferred income tax asset	(13,137)	(694)
Deferred income tax (recovery) expense	12,443	245
Deferred revenue [Member]
Disclosure of temporary difference, unused tax losses and unused tax credits [line items]
Deferred income tax asset	(809)	(112)
Deferred income tax (recovery) expense	697	(12,839)
Other [Member]
Disclosure of temporary difference, unused tax losses and unused tax credits [line items]
Deferred income tax asset	3,982	1,234
Deferred income tax (recovery) expense	(4,516)	(7,755)
Deferred income tax liability	7,702	3,629
Deferred income tax expense (recovery)	4,073	7,302
Income tax effect of temporary differences [Member]
Disclosure of temporary difference, unused tax losses and unused tax credits [line items]
Deferred income tax asset	94,070	69,950
Deferred income tax (recovery) expense	(26,794)	(58,385)
Deferred income tax liability	220,568	233,218
Deferred income tax expense (recovery)	(13,111)	(74,094)
Deferred income tax (liability) asset	(126,498)	(163,268)
et deferred income tax expense (recovery)	$ (39,905)	$ (132,479)

Income and mining taxes (Sche_6

Income and mining taxes (Schedule of temporary differences not recognized) (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Disclosure of temporary difference, unused tax losses and unused tax credits [line items]
Temporary differences not recognized	$ 573,971	$ 531,338
Property, plant and equipment [Member]
Disclosure of temporary difference, unused tax losses and unused tax credits [line items]
Temporary differences not recognized	46,718	33,269
Capital losses [Member]
Disclosure of temporary difference, unused tax losses and unused tax credits [line items]
Temporary differences not recognized	166,227	159,545
Other employee benefits [Member]
Disclosure of temporary difference, unused tax losses and unused tax credits [line items]
Temporary differences not recognized	51,226	68,866
Asset retirement obligations [Member]
Disclosure of temporary difference, unused tax losses and unused tax credits [line items]
Temporary differences not recognized	193,898	146,679
Non-capital losses [Member]
Disclosure of temporary difference, unused tax losses and unused tax credits [line items]
Temporary differences not recognized	$ 115,902	$ 122,979

Income and mining taxes (Sche_7

Income and mining taxes (Schedule of temporary differences - deferred mining tax assets and liabilities) (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Disclosure of temporary difference, unused tax losses and unused tax credits [line items]
Net deferred tax asset (liability)	$ (127,534)	$ (167,882)	$ (308,577)
Mining tax effect of temporary differences recognized [Member] \| Canada [Member]
Disclosure of temporary difference, unused tax losses and unused tax credits [line items]
Net deferred tax asset (liability)	7,829	5,095
Mining tax effect of temporary differences recognized [Member] \| Peru [Member]
Disclosure of temporary difference, unused tax losses and unused tax credits [line items]
Net deferred tax asset (liability)	$ (8,865)	$ (9,710)

Share capital (Schedule of deta

Share capital (Schedule of detailed information about shares activity) (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Disclosure of classes of share capital [line items]
Beginning and end of year - Amount	$ 1,699,806	$ 1,848,123	$ 2,178,856
Share capital [Member]
Disclosure of classes of share capital [line items]
Beginning and end of year - Common shares	261,272,151	261,272,151
Beginning and end of year - Amount	$ 1,777,340	$ 1,777,340	$ 1,777,340

Share-based compensation (Sched

Share-based compensation (Schedule of number and weighted average exercise prices of other equity instruments) (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2020$ / shares	Dec. 31, 2020USD ($)	Dec. 31, 2019$ / shares	Dec. 31, 2019USD ($)
Deferred Share Unit [Member]
Disclosure of terms and conditions of share-based payment arrangement [line items]
Number of units granted during the year		465,889		337,999
Weighted average price (C$/unit) \| $ / shares	$ 4.10		$ 5.89
Expenses recognized during the year		$ 5,149		$ 1,157
Payments made during the year		$ 497		$ 1,668
Restricted Share Unit [Member]
Disclosure of terms and conditions of share-based payment arrangement [line items]
Number of restricted share units, beginning of year		2,223,999		3,666,867
Number of units granted during the year		1,388,786		1,080,741
Credits for dividends		17,587		7,554
Number of units forfeited during the year		(44,678)		(573,914)
Number of units vested		(645,357)		(1,957,249)
Number of restricted share units, end of year		2,940,337		2,223,999
Weighted average price (C$/unit) \| $ / shares	3.98		8.98
Expenses recognized during the year		$ 6,750		$ 1,557
Payments made during the year		$ 2,646		$ 9,380
Performance Share Unit [Member]
Disclosure of terms and conditions of share-based payment arrangement [line items]
Number of performance units, beginning of year		0		0
Number of units granted during the year		1,089,569		0
Credits for dividends		6,046		0
Number of performance units, end of year		1,095,615		0
Weighted average price (C$/unit) \| $ / shares	$ 3.97		$ 0
Expenses recognized during the year		$ 1,987		$ 0
Payments made during the year		$ 0		$ 0

Share-based compensation (Sch_2

Share-based compensation (Schedule of weighted average fair value assumptions used in the Black-Scholes valuation) (Details)	12 Months Ended
	Dec. 31, 2020Month$ / shares
Disclosure of terms and conditions of share-based payment arrangement [abstract]
Weighted average share price at grant date (CAD)	$ 3.77
Risk-free rate	1.14%
Expected dividend yield	0.50%
Expected stock price volatility (based on historical volatility)	57.00%
Expected life of option (months) \| Month	84
Weighted average per share fair value of stock options granted (CAD)	$ 2.02

Share-based compensation (Sch_3

Share-based compensation (Schedule of range of exercise prices of share options) (Details)	12 Months Ended
	Dec. 31, 2020Share$ / shares	Dec. 31, 2019Share$ / shares	Dec. 31, 2018Share$ / shares
Disclosure of range of exercise prices of outstanding share options [line items]
Number of options outstanding \| Share	1,563,189	0	0
Weighted average exercise price	$ 3.77	$ 0	$ 0
Range of exercise prices $3.76 - $3.92 [Member]
Disclosure of range of exercise prices of outstanding share options [line items]
Number of options outstanding \| Share	1,563,189
Weighted average remaining contractual life (years)	6 years 1 month 28 days
Weighted average exercise price	$ 3.77
Number of options exercisable \| Share	0
Weighted average share price at exercise date	$ 0
Range of exercise prices $3.76 - $3.92 [Member] \| Bottom of range [Member]
Disclosure of range of exercise prices of outstanding share options [line items]
Weighted average exercise price	3.76
Range of exercise prices $3.76 - $3.92 [Member] \| Top of range [Member]
Disclosure of range of exercise prices of outstanding share options [line items]
Weighted average exercise price	$ 3.92

Share-based compensation (Sch_4

Share-based compensation (Schedule of number and weighted average exercise prices of share options) (Details)	12 Months Ended
	Dec. 31, 2020Share$ / shares	Dec. 31, 2019Share$ / shares
Disclosure of terms and conditions of share-based payment arrangement [abstract]
Number of shares subject to option, beginning of year \| Share	0	0
Weighted average exercise price of share options outstanding at beginning of period \| $ / shares	$ 0	$ 0
Number of units granted during the year \| Share	1,581,385	0
Weighted average exercise price of options granted \| $ / shares	$ 3.77	$ 0
Stock options forfeited \| Share	(18,196)	0
Weighted average exercise price of options forfeited \| $ / shares	$ 3.76	$ 0
Number of shares subject to option, end of year \| Share	1,563,189	0
Weighted average exercise price of share options outstanding at end of period \| $ / shares	$ 3.77	$ 0

Earnings per share (Schedule of

Earnings per share (Schedule of earnings per share) (Details) - shares	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Basic earnings per share [abstract]
Basic and diluted weighted average common shares outstanding	261,272,151	261,272,151

Financial instruments (Schedule

Financial instruments (Schedule of fair value measurement) (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Disclosure of fair value measurement of assets [line items]
Cash and cash equivalents	$ 439,135	$ 396,146	$ 515,497
Non-hedge derivative assets	2,736	1,712
Prepayment option - embedded derivative	49,754	2,585
Investments	15,669	11,287
Deferred Rosemont acquisition consideration	25,961	24,491
Finance leases	63,514	81,947	$ 89,215
Other financial liabilities	219,091	67,860
Senior unsecured notes	1,277,124	1,050,126
Embedded derivatives		9,074
Gold prepayment liability	137,031	0
Non-hedge derivative liabilities	15,312	10,295
Fair value [Member]
Disclosure of fair value measurement of assets [line items]
Cash and cash equivalents	439,135	396,146
Restricted cash	337	337
Trade and other receivables	114,381	91,046
Non-hedge derivative assets	2,736	1,712
Investments	15,669	11,287
Total financial assets	572,258	500,528
Trade and other payables	209,413	184,604
Deferred Rosemont acquisition consideration	25,961	24,491
Other financial liabilities	41,912	21,338
Senior unsecured notes	1,277,124	1,050,126
Embedded derivatives	0	9,074
Gold prepayment liability	137,031	0
Non-hedge derivative liabilities	15,312	10,295
Total financial liabilities	1,706,753	1,299,928
Net financial liability	(1,134,495)	(799,400)
Carrying Amounts [Member]
Disclosure of fair value measurement of assets [line items]
Cash and cash equivalents	439,135	396,146
Restricted cash	337	337
Trade and other receivables	114,381	91,046
Non-hedge derivative assets	2,736	1,712
Investments	15,669	11,287
Total financial assets	572,258	500,528
Trade and other payables	209,413	184,604
Deferred Rosemont acquisition consideration	25,961	24,491
Other financial liabilities	40,787	24,000
Senior unsecured notes	1,139,695	991,558
Embedded derivatives	0	9,074
Gold prepayment liability	137,031	0
Non-hedge derivative liabilities	15,312	10,295
Total financial liabilities	1,568,199	1,244,022
Net financial liability	$ (995,941)	$ (743,494)

Financial instruments (Schedu_2

Financial instruments (Schedule of significant unobservable inputs used in fair value measurement of assets and liabilities) (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Disclosure of fair value measurement of assets [line items]
Non-hedge derivatives	$ 2,736	$ 1,712
Investments at FVTPL	15,669	11,287
Financial assets measured at fair value	18,405	12,999
Embedded derivatives		9,074
Non-hedge derivatives	15,312	10,295
Gold prepayment liability	137,031	0
Other financial liabilities	41,912	21,338
Senior unsecured notes	1,277,124	1,050,126
Financial liabilities measured at fair value	1,471,379	1,090,833
Level 1 [Member]
Disclosure of fair value measurement of assets [line items]
Non-hedge derivatives	0	0
Investments at FVTPL	15,669	11,287
Financial assets measured at fair value	15,669	11,287
Embedded derivatives		0
Non-hedge derivatives	0	0
Gold prepayment liability	0
Other financial liabilities	0	0
Senior unsecured notes	1,277,124	1,050,126
Financial liabilities measured at fair value	1,277,124	1,050,126
Level 2 [Member]
Disclosure of fair value measurement of assets [line items]
Non-hedge derivatives	2,736	1,712
Investments at FVTPL	0	0
Financial assets measured at fair value	2,736	1,712
Embedded derivatives		9,074
Non-hedge derivatives	15,312	10,295
Gold prepayment liability	137,031
Other financial liabilities	0	0
Senior unsecured notes	0	0
Financial liabilities measured at fair value	152,343	19,369
Level 3 [Member]
Disclosure of fair value measurement of assets [line items]
Non-hedge derivatives	0	0
Investments at FVTPL	0	0
Financial assets measured at fair value	0	0
Embedded derivatives		0
Non-hedge derivatives	0	0
Gold prepayment liability	0
Other financial liabilities	41,912	21,338
Senior unsecured notes	0	0
Financial liabilities measured at fair value	$ 41,912	$ 21,338

Financial instruments (Schedu_3

Financial instruments (Schedule of net position consisted of contracts awaiting final pricing) (Details) - Embedded Derivatives [Member] lb in Thousands	Dec. 31, 2020lboz$ / OZ$ / lbs	Dec. 31, 2019lboz$ / OZ$ / lbs
Copper [Member]
Disclosure of risk management strategy related to hedge accounting [line items]
Sales awaiting final pricing \| lb	47,901	72,977
Average YTD price ($/unit) \| $ / lbs	3.52	2.80
Gold [Member]
Disclosure of risk management strategy related to hedge accounting [line items]
Sales awaiting final pricing \| oz	18,106	16,152
Average YTD price ($/unit) \| $ / OZ	1,894	1,522
Silver [Member]
Disclosure of risk management strategy related to hedge accounting [line items]
Sales awaiting final pricing \| oz	123,380	124,371
Average YTD price ($/unit) \| $ / OZ	26.35	17.86

Financial instruments (Schedu_4

Financial instruments (Schedule of detailed information about foreign currency risk) (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Disclosure of detailed information about financial instruments [line items]
Cash and cash equivalents	$ 439,135	$ 396,146	$ 515,497
Other financial assets	18,742	13,336
Other financial liabilities	(219,091)	(67,860)
Currency risk [Member] \| Amounts Held In CAD [Member]
Disclosure of detailed information about financial instruments [line items]
Cash and cash equivalents	7,791	8,394
Trade and other receivables	31	374
Other financial assets	15,669	11,287
Trade and other payables	(6,104)	(5,719)
Other financial liabilities	0	0
Net financial liability	17,387	14,336
Currency risk [Member] \| Amounts Held In USD [Member]
Disclosure of detailed information about financial instruments [line items]
Cash and cash equivalents	3,895	21,217
Trade and other receivables	43,316	56,998
Other financial assets	0	0
Trade and other payables	(1,419)	(435)
Other financial liabilities	0	0
Net financial liability	45,792	77,780
Currency risk [Member] \| Amounts Held In PEN [Member]
Disclosure of detailed information about financial instruments [line items]
Cash and cash equivalents	4,141	7,617
Trade and other receivables	36,951	25,413
Other financial assets	0	0
Trade and other payables	(34,622)	(22,618)
Other financial liabilities	(40,787)	(24,000)
Net financial liability	$ (34,317)	$ (13,588)

Financial instruments (Schedu_5

Financial instruments (Schedule of foreign currency risk) (Details) - Currency risk [Member] - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
USD / CAD exchange rate [Member]
Disclosure of detailed information about financial instruments [line items]
Sensitivity analysis, variance, percentage	10.00%	10.00%
Effect of variance increase on after-tax profit	$ 1.1	$ 3.4
Effect of variance decrease on after-tax profit	$ (1.4)	$ (4.1)
USD / PEN exchange rate [Member]
Disclosure of detailed information about financial instruments [line items]
Sensitivity analysis, variance, percentage	10.00%	10.00%
Effect of variance increase on after-tax profit	$ 2	$ 0.8
Effect of variance decrease on after-tax profit	$ (2.5)	$ (1)

Financial instruments - (Schedu

Financial instruments - (Schedule of commodity price risk) (Details) - Commodity price risk [Member] $ in Millions	12 Months Ended
	Dec. 31, 2020USD ($)$ / lbs	Dec. 31, 2019USD ($)$ / lbs
Copper prices [Member]
Disclosure of detailed information about financial instruments [line items]
Sensitivity analysis, variance, price \| $ / lbs	0.30	0.30
Effect of variance increase on after-tax profit	$ (1.4)	$ (2)
Effect of variance decrease on after-tax profit	$ 1.4	$ 2
Zinc prices [Member]
Disclosure of detailed information about financial instruments [line items]
Sensitivity analysis, variance, price \| $ / lbs	0.10	0.10
Effect of variance increase on after-tax profit	$ 0.3	$ 1
Effect of variance decrease on after-tax profit	$ (0.3)	$ (1)

Financial instruments - (Sche_2

Financial instruments - (Schedule of share price risk) (Details) - Share price risk [Member] - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Disclosure of detailed information about financial instruments [line items]
Sensitivity analysis, variance, percentage	25.00%	25.00%
Effect of variance increase on after-tax profit	$ 3.9	$ 2.8
Effect of variance decrease on after-tax profit	$ (3.9)	$ (2.8)

Financial instruments - (Sche_3

Financial instruments - (Schedule of interest rate risk) (Details) - Interest rate risk [Member] - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Disclosure of detailed information about financial instruments [line items]
Sensitivity analysis, variance, percentage	2.00%	2.00%
Effect of variance increase on after-tax profit	$ (38)	$ 2.3
Effect of variance decrease on after-tax profit	$ 48.5	$ (2.6)

Financial instruments - (Sche_4

Financial instruments - (Schedule of liquidity risk) (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Disclosure of detailed information about financial instruments [line items]
Cash and cash equivalents	$ 439,135	$ 396,146	$ 515,497
Non-hedge derivative assets	2,736	1,712
Other financial liabilities	(219,091)	(67,860)
Long-term debt, including embedded derivative	(1,135,675)	(985,255)
Gold prepayment obligation	(137,031)	0
Finance lease liabilities	(63,514)	(81,947)	$ (89,215)
Embedded derivative		(9,074)
Derivative financial liabilities	(15,312)	(10,295)
Within one year [Member]
Disclosure of detailed information about financial instruments [line items]
Cash and cash equivalents	439,135	396,146
Restricted cash	337	337
Trade and other receivables	114,381	89,451
Non-hedge derivative assets	2,736	1,712
Assets used to manage liquidity risk	556,589	487,646
Trade and other payables, including embedded derivative	(209,413)	(184,604)
Other financial liabilities	(12,097)	(6,672)
Deferred Rosemont acquisition consideration	0	0
Long-term debt, including embedded derivative	(87,966)	(72,165)
Gold prepayment obligation	0
Non-derivative financial liabilities	(309,476)	(263,441)
Embedded derivative		(9,074)
Non-hedge derivative contracts	(15,312)	(10,295)
Derivative financial liabilities	(15,312)	(19,369)
13-36 months [Member]
Disclosure of detailed information about financial instruments [line items]
Cash and cash equivalents	0	0
Restricted cash	0
Trade and other receivables	0	0
Non-hedge derivative assets	0	0
Assets used to manage liquidity risk	0	0
Trade and other payables, including embedded derivative	0	0
Other financial liabilities	(9,483)	(4,811)
Deferred Rosemont acquisition consideration	(20,000)	(10,000)
Long-term debt, including embedded derivative	(168,188)	(149,500)
Gold prepayment obligation	(137,031)
Non-derivative financial liabilities	(334,702)	(164,311)
Embedded derivative		0
Non-hedge derivative contracts	0	0
Derivative financial liabilities	0	0
37-60 months [Member]
Disclosure of detailed information about financial instruments [line items]
Cash and cash equivalents	0	0
Restricted cash	0
Trade and other receivables	0	0
Non-hedge derivative assets	0	0
Assets used to manage liquidity risk	0	0
Trade and other payables, including embedded derivative	0	0
Other financial liabilities	(6,578)	(4,734)
Deferred Rosemont acquisition consideration	(10,000)	(20,000)
Long-term debt, including embedded derivative	(742,125)	(1,128,875)
Gold prepayment obligation	0
Non-derivative financial liabilities	(758,703)	(1,153,609)
Embedded derivative		0
Non-hedge derivative contracts	0	0
Derivative financial liabilities	0	0
More than 60 months [Member]
Disclosure of detailed information about financial instruments [line items]
Cash and cash equivalents	0	0
Restricted cash	0
Trade and other receivables	0	1,595
Non-hedge derivative assets	0	0
Assets used to manage liquidity risk	0	1,595
Trade and other payables, including embedded derivative	0	0
Other financial liabilities	(30,679)	(17,506)
Deferred Rosemont acquisition consideration	0	0
Long-term debt, including embedded derivative	(728,625)	0
Gold prepayment obligation	0
Non-derivative financial liabilities	(759,304)	(17,506)
Embedded derivative		0
Non-hedge derivative contracts	0	0
Derivative financial liabilities	0	0
Carrying amount [Member]
Disclosure of detailed information about financial instruments [line items]
Cash and cash equivalents	439,135	396,146
Restricted cash	337	337
Trade and other receivables	114,381	91,046
Non-hedge derivative assets	2,736	1,712
Assets used to manage liquidity risk	556,589	489,241
Trade and other payables, including embedded derivative	(209,413)	(184,604)
Other financial liabilities	(40,787)	(24,000)
Deferred Rosemont acquisition consideration	(25,961)	(24,491)
Long-term debt, including embedded derivative	(1,139,695)	(991,558)
Gold prepayment obligation	(137,031)
Non-derivative financial liabilities	(1,552,887)	(1,224,653)
Embedded derivative		(9,074)
Non-hedge derivative contracts	(15,312)	(10,295)
Derivative financial liabilities	(15,312)	(19,369)
Contractual cash flows [Member]
Disclosure of detailed information about financial instruments [line items]
Cash and cash equivalents	439,135	396,146
Restricted cash	337	337
Trade and other receivables	114,381	91,046
Non-hedge derivative assets	2,736	1,712
Assets used to manage liquidity risk	556,589	489,241
Trade and other payables, including embedded derivative	(209,413)	(184,604)
Other financial liabilities	(58,837)	(33,723)
Deferred Rosemont acquisition consideration	(30,000)	(30,000)
Long-term debt, including embedded derivative	(1,726,904)	(1,350,540)
Gold prepayment obligation	(137,031)
Non-derivative financial liabilities	(2,162,185)	(1,598,867)
Embedded derivative		(9,074)
Non-hedge derivative contracts	(15,312)	(10,295)
Derivative financial liabilities	$ (15,312)	$ (19,369)

Commitments and contingencies -

Commitments and contingencies - (Schedule of maturity analysis of operating lease payments) (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Disclosure of maturity analysis of operating lease payments [line items]
Minimum lease payments payable under non-cancellable operating lease	$ 60,365	$ 84,255
Within one year [Member]
Disclosure of maturity analysis of operating lease payments [line items]
Minimum lease payments payable under non-cancellable operating lease	58,173	57,860
After one year but not more than five years [Member]
Disclosure of maturity analysis of operating lease payments [line items]
Minimum lease payments payable under non-cancellable operating lease	2,192	26,395
More than five years [Member]
Disclosure of maturity analysis of operating lease payments [line items]
Minimum lease payments payable under non-cancellable operating lease	$ 0	$ 0

Related parties - (Schedule of

Related parties - (Schedule of Subsidiaries) (Details)	12 Months Ended
Related parties - (Schedule of Subsidiaries) (Details)	Dec. 31, 2020	Dec. 31, 2019
HudBay Marketing & Sales Inc. [Member]
Disclosure of transactions between related parties [line items]
Beneficial ownership of ultimate controlling party (HudBay Minerals Inc.)	100.00%	100.00%
HudBay Peru Inc. [Member]
Disclosure of transactions between related parties [line items]
Beneficial ownership of ultimate controlling party (HudBay Minerals Inc.)	100.00%	100.00%
HudBay Peru S.A.C. [Member]
Disclosure of transactions between related parties [line items]
Beneficial ownership of ultimate controlling party (HudBay Minerals Inc.)	100.00%	100.00%
HudBay (BVI) Inc. [Member]
Disclosure of transactions between related parties [line items]
Beneficial ownership of ultimate controlling party (HudBay Minerals Inc.)	100.00%	100.00%
Hudbay Arizona Inc. [Member]
Disclosure of transactions between related parties [line items]
Beneficial ownership of ultimate controlling party (HudBay Minerals Inc.)	100.00%	100.00%
Rosemont Copper Company [Member]
Disclosure of transactions between related parties [line items]
Beneficial ownership of ultimate controlling party (HudBay Minerals Inc.)	100.00%	100.00%

Related parties - (Schedule o_2

Related parties - (Schedule of Information about key management personnel) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Disclosure of transactions between related parties [abstract]
Short-term employee benefits	$ 7,951	$ 8,319
Post-employment benefits	639	762
Long-term share-based awards	6,381	6,966
Total key management personnel compensation	$ 14,971	$ 16,047

Supplementary cash flow infor_4

Supplementary cash flow information (Schedule of change in non-cash working capital) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Supplementary Cash Flow Information [Abstract]
Trade and other receivables	$ (37,720)	$ 3,252
Other financial assets/liabilities	4,077	12,540
Inventories	(2,867)	(11,759)
Prepaid expenses	(3,722)	(3,484)
Trade and other payables	36,247	5,613
Provisions and other liabilities	1,602	(2,590)
Increase (decrease) in working capital	$ (2,383)	$ 3,572

Segmented information (Schedule

Segmented information (Schedule of segments) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Disclosure of operating segments [line items]
Revenue from external customers	$ 1,092,418	$ 1,237,439
Cost of sales
Mine operating costs	691,591	741,342
Depreciation and amortization	361,827	344,555
Gross profit	39,000	151,542
Selling and administrative expenses	41,408	36,170
Exploration and evaluation expenses	17,196	30,774
Other expenses	17,583	51,116
Impairment loss	0	322,249
Results from operating activities	(37,187)	(288,767)
Net interest expense on long term debt	82,712	68,375
Accretion on streaming arrangements	56,670	69,772
Change in fair value of financial instruments	(29,370)	8,247
Other net finance costs	31,890	17,602
Loss before tax	(179,089)	(452,763)
Tax recovery	(34,505)	(108,953)
Loss for the year	(144,584)	(343,810)
Manitoba [Member]
Disclosure of operating segments [line items]
Revenue from external customers	615,699	537,421
Cost of sales
Mine operating costs	391,504	385,159
Depreciation and amortization	177,552	135,429
Gross profit	46,643	16,833
Selling and administrative expenses	0	0
Exploration and evaluation expenses	6,491	18,476
Other expenses	8,382	8,201
Impairment loss		0
Results from operating activities	31,770	(9,844)
Peru [Member]
Disclosure of operating segments [line items]
Revenue from external customers	476,719	700,018
Cost of sales
Mine operating costs	300,087	356,183
Depreciation and amortization	184,275	209,126
Gross profit	7,643	134,709
Selling and administrative expenses	0	0
Exploration and evaluation expenses	6,295	5,804
Other expenses	4,901	14,022
Impairment loss		0
Results from operating activities	(18,839)	114,883
Arizona [Member]
Disclosure of operating segments [line items]
Revenue from external customers	0	0
Cost of sales
Mine operating costs	0	0
Depreciation and amortization	0	0
Gross profit	0	0
Selling and administrative expenses	0	0
Exploration and evaluation expenses	3,870	0
Other expenses	2,066	28,149
Impairment loss		322,249
Results from operating activities	(5,936)	(350,398)
Corporate and other activities [Member]
Disclosure of operating segments [line items]
Revenue from external customers	0	0
Cost of sales
Mine operating costs	0	0
Depreciation and amortization	0	0
Gross profit	0	0
Selling and administrative expenses	41,408	36,170
Exploration and evaluation expenses	540	6,494
Other expenses	2,234	744
Impairment loss		0
Results from operating activities	$ (44,182)	$ (43,408)

Segmented information (Schedu_2

Segmented information (Schedule of segments, assets and liabilities) (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Disclosure of operating segments [line items]
Total assets	$ 4,666,645	$ 4,461,057
Total liabilities	2,966,839	2,612,934
Property, plant and equipment	3,731,655	3,662,559
Manitoba [Member]
Disclosure of operating segments [line items]
Total assets	801,691	779,896
Total liabilities	562,013	556,267
Property, plant and equipment	699,884	684,679
Peru [Member]
Disclosure of operating segments [line items]
Total assets	2,535,939	2,556,895
Total liabilities	973,756	926,642
Property, plant and equipment	2,290,097	2,253,404
Arizona [Member]
Disclosure of operating segments [line items]
Total assets	718,982	700,799
Total liabilities	76,926	78,988
Property, plant and equipment	709,939	691,538
Corporate and other activities [Member]
Disclosure of operating segments [line items]
Total assets	610,033	423,467
Total liabilities	1,354,144	1,051,037
Property, plant and equipment	31,735	32,938
Corporate and other activities [Member] \| Nevada [Member]
Disclosure of operating segments [line items]
Property, plant and equipment	$ 27,500	$ 27,300

Segmented information (Schedu_3

Segmented information (Schedule of segments, additions to property, plant and equipment) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Disclosure of operating segments [line items]
Additions to property, plant and equipment	$ 386,790	$ 284,963
Manitoba [Member]
Disclosure of operating segments [line items]
Additions to property, plant and equipment	159,313	143,418
Peru [Member]
Disclosure of operating segments [line items]
Additions to property, plant and equipment	208,805	101,717
Arizona [Member]
Disclosure of operating segments [line items]
Additions to property, plant and equipment	18,640	38,923
Corporate and other activities [Member]
Disclosure of operating segments [line items]
Additions to property, plant and equipment	$ 32	$ 905

Segmented information (Schedu_4

Segmented information (Schedule of geographical areas, revenue by customer location) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Disclosure of operating segments [line items]
Revenue from external customers	$ 1,092,418	$ 1,237,439
Canada [Member]
Disclosure of operating segments [line items]
Revenue from external customers	422,403	418,636
China [Member]
Disclosure of operating segments [line items]
Revenue from external customers	215,278	158,795
United States [Member]
Disclosure of operating segments [line items]
Revenue from external customers	206,906	209,382
Philippines [Member]
Disclosure of operating segments [line items]
Revenue from external customers	77,575	71,506
Peru [Member]
Disclosure of operating segments [line items]
Revenue from external customers	56,437	110,411
Switzerland [Member]
Disclosure of operating segments [line items]
Revenue from external customers	55,703	162,167
Singapore [Member]
Disclosure of operating segments [line items]
Revenue from external customers	29,314	71,506
Germany [Member]
Disclosure of operating segments [line items]
Revenue from external customers	11,725	10,731
Other [Member]
Disclosure of operating segments [line items]
Revenue from external customers	$ 17,077	$ 24,305