XML 87 R73.htm IDEA: XBRL DOCUMENT
v3.8.0.1

Tax situation (Tables) | 12 Months Ended
--- | ---
Dec. 31, 2017
Disclosure Of Income Tax Explanatory [Line Items] |
Disclosure Of Detailed Information Income Tax Years To Review [Text Block] | The Income Tax and Value Added Tax returns for the following years are open to review by the Tax Authorities:
Entity | Years open to review by the Tax Authorities
Compañía de Minas Buenaventura S.A.A. | 2013-2017
Bisa Construcción S.A. (absorbed by Buenaventura Ingenieros S.A. in 2015) | 2014-2015
Buenaventura Ingenieros S.A. | 2013, 2015-2017
Compañía de Exploraciones, Desarrollo e Inversiones Mineras S.A.C. – CEDIMIN (absorbed by the Company in 2013) | 2013
Compañía Minera Condesa S.A. | 2013-2017
Compañía Minera Colquirrumi S.A. | 2013-2017
Consorcio Energético de Huancavelica S.A. | 2013-2017
Contacto Corredores de Seguros S.A. | 2014-2017
El Molle Verde S.A.C. | 2013-2017
Empresa de Generación Huanza S.A. | 2013, 2015, 2016, 2017
Inversiones Colquijirca S.A. | 2013-2017
Minera La Zanja S.R.L. | 2014-2017
Sociedad Minera El Brocal S.A.A. | 2014-2017
S.M.R.L. Chaupiloma Dos de Cajamarca | 2014-2017
Procesadora Industrial Río Seco S. A. | 2014-2017
Apu Coropuna S.R.L. | 2013-2017
Cerro Hablador S. A. C. | 2013-2017
Minera Azola S. R. L. | 2014-2017
Minera Yanacocha SRL and subsidiary [Member] |
Disclosure Of Income Tax Explanatory [Line Items] |
Disclosure Of Detailed Information Income Tax Years To Review [Text Block] | The Company has entered into the following tax stability agreements, each with a term of 15 years:
Mine | Effective | Date of the Tax Agreement | Tax Regimes in Force
Cerro Yanacocha | January 1, 2000 | September 16, 1998 | May 22, 1997
La Quinua | January 1, 2004 | August 25, 2003 | August 25, 2003
Disclosure Of Detailed Information About Income Tax Provision [Text Block] | The Company's income tax provision consisted of the following:
|  | 2017 |  | 2016 |  | 2015 |
|  | US$(000) |  | US$(000) |  | US$(000) |
Current Peruvian income tax |  |  | 3,877 |  |  | 41,105 |  |  | 98,319 |
Royalties and mining taxes |  |  | 4,944 |  |  | 10,249 |  |  | 21,721 |
Other taxes |  |  | 211 |  |  | 323 |  |  | 639 |
Income tax prior year adjustments |  |  | (2,006) |  |  | (2,092) |  |  | (1,766) |
Income tax prior years refunds |  |  | - |  |  | (6,458) |  |  | - |
Current income tax expense |  |  | 7,026 |  |  | 43,127 |  |  | 118,913 |
Deferred income tax expense (benefit) |  |  | - |  |  | - |  |  | 483,804 |
Income tax expense |  |  | 7,026 |  |  | 43,127 |  |  | 602,717 |
Disclosure of detailed deferred taxes [Text Block] | Components of deferred income tax assets (liabilities) are as follows:
|  | 2017 |  | 2016 |
|  | US$(000) |  | US$(000) |
Deferred income tax assets, net |  |  |  |  |  |  |
Property, plant and mine development |  |  | 571,210 |  |  | 608,783 |
Reclamation |  |  | 233,843 |  |  | 160,261 |
Accounts payable and accrued expenses |  |  | 78,241 |  |  | 64,703 |
Inventories |  |  | 61,435 |  |  | 60,018 |
Other |  |  | 3,073 |  |  | 3,077 |
|  |  | 947,802 |  |  | 896,842 |
Allowance of deferred income tax asset |  |  | (947,802) |  |  | (896,842) |
Net deferred income tax asset |  |  | - |  |  | - |
Disclosure Of Tax Expense Reconciliation Of Accounting Profit Multiplied By Applicable Tax Rates [Text Block] | Below is a reconciliation of tax expense and the accounts profit multiplied by the statutory tax rate for the years 2017 and 2016:
|  | 2017 |  | 2016 |  | 2015 |
|  | US$(000) |  | US$(000) |  | US$(000) |
Income (loss) before income tax |  |  | (168,428) |  |  | (1,000,625) |  |  | 152,522 |
Peruvian statutory tax rate |  |  | 29.5 | % |  | 28 | % |  | 28 | %
Income tax expense (income) |  |  | (49,686) |  |  | (280,175) |  |  | 42,706 |
Valuation allowance on deferred tax asset |  |  | 50,960 |  |  | 386,763 |  |  | 510,004 |
Effect of change in income tax rate |  |  | - |  |  | (66,667) |  |  | 16,576 |
Mining taxes |  |  | 3,530 |  |  | 7,392 |  |  | 15,639 |
Non-deductible expenses |  |  | 4,204 |  |  | 3,296 |  |  | 15,288 |
Adjustment due to income tax rate applicable to la Quinua |  |  | (124) |  |  | (1,024) |  |  | 2,504 |
Income tax prior years refunds / payments |  |  | (1,858) |  |  | (6,458) |  |  | - |
Total income tax expense |  |  | 7,026 |  |  | 43,127 |  |  | 602,717 |
Disclosure Of Temporary Difference Unused Tax Losses And Unused Tax Credits Explanatory [Text Block] | The Company recognizes the effect of temporary differences between the accounting base for financial reporting purposes and the tax base. The composition of this item is made up as follows:
|  | December 31, |  | December 31, |  | December 31, |
|  | 2017 |  | 2016 |  | 2015 |
|  | US$(000) |  | US$(000) |  | US$(000) |
Income tax |  |  |  |  |  |  |  |  |  |
Asset |  |  |  |  |  |  |  |  |  |
Royalty accrual |  |  | 127,475 |  |  | - |  |  | - |
Provision for remediation and mine closure |  |  | 12,083 |  |  | 9,180 |  |  | 5,638 |
Provision for mining taxes |  |  | 8,742 |  |  | 4,003 |  |  | 1,505 |
Unpaid vacations |  |  | 5,293 |  |  | 4,055 |  |  | 2,515 |
SUNAT Assessments |  |  | 4,077 |  |  | - |  |  | - |
Cost of net asset for the construction of the tailing dam |  |  | 2,007 |  |  | 2,321 |  |  | 1,682 |
Development costs |  |  | 183 |  |  | 228 |  |  | 332 |
Price adjustment of copper concentrates and cathode |  |  | - |  |  | - |  |  | 7,849 |
Other provisions |  |  | 4,240 |  |  | 5,248 |  |  | 4,750 |
|  |  | 164,100 |  |  | 25,035 |  |  | 24,271 |
Liability |  |  |  |  |  |  |  |  |  |
Difference in depreciation method |  |  | 261,434 |  |  | 283,882 |  |  | 245,670 |
Price adjustment of copper concentrate and cathode |  |  | 25,840 |  |  | 24,128 |  |  | - |
|  | December 31, |  | December 31, |  | December 31, |
|  | 2017 |  | 2016 |  | 2015 |
|  | US$(000) |  | US$(000) |  | US$(000) |
Stripping activity asset |  |  | 22,014 |  |  | 23,594 |  |  | 17,820 |
Difference in valuation of inventories |  |  | 16,264 |  |  | 25,087 |  |  | 10,997 |
Debt issuance costs |  |  | 2,663 |  |  | - |  |  | - |
|  |  | 328,215 |  |  | 356,691 |  |  | 274,487 |
Deferred liabilities, net |  |  | 164,115 |  |  | 331,656 |  |  | 250,216 |
Supplementary retirement fund |  |  |  |  |  |  |  |  |  |
Deferred liability |  |  | 1,890 |  |  | 3,458 |  |  | 2,937 |
Total deferred income tax liability, net |  |  | 166,005 |  |  | 335,114 |  |  | 253,153 |
Sociedad Minera El Brocal S.A.A. [Member] |
Disclosure Of Income Tax Explanatory [Line Items] |
Disclosure Of Detailed Information About Income Tax Provision [Text Block] | The income tax expenses (benefit) for the years ended December 31, 2017, 2016 and 2015 is shown below:
|  | 2017 |  | 2016 |  | 2015 |
|  | US$(000) |  | US$(000) |  | US$(000) |
Income tax |  |  |  |  |  |  |  |  |  |
Current |  |  | 430,974 |  |  | 141,153 |  |  | (832) |
Deferred |  |  | (167,541) |  |  | 81,441 |  |  | 32,015 |
|  |  | 263,433 |  |  | 222,594 |  |  | 31,183 |
Mining taxes |  |  |  |  |  |  |  |  |  |
Current mining royalty and special mining tax |  |  | 213,280 |  |  | 37,763 |  |  | 14,599 |
Supplementary retirement fund |  |  |  |  |  |  |  |  |  |
Current |  |  | 10,897 |  |  | 2,205 |  |  | 54 |
Deferred |  |  | (1,567) |  |  | 520 |  |  | 410 |
|  |  | 9,330 |  |  | 2,725 |  |  | 464 |
Income tax expense reported in the statements of comprehensive income |  |  | 486,043 |  |  | 263,082 |  |  | 46,246 |
Disclosure of detailed information about the other tax assesment [Text Block] | The Company has also received assessments from SUNAT for additional taxes (other than the mining royalty explained in 14(d) above), including penalties and interest. The Company has filed or will file objections to the assessments because it believes it has properly determined and paid its taxes. A summary of these assessments follows:
|  |  |  | Penalty and |  |  |
Year |  | Taxes |  | interest |  | Total |
|  | US$(000) |  | US$(000) |  | US$(000) |
2003 – 2005 |  |  | 15,909 |  |  | 54,053 |  |  | 69,962 |
2006 |  |  | 6,545 |  |  | 59,454 |  |  | 65,999 |
2007 |  |  | 12,376 |  |  | 17,809 |  |  | 30,185 |
2008 |  |  | 20,797 |  |  | 12,968 |  |  | 33,765 |
2009 |  |  | 58,495 |  |  | 49,112 |  |  | 107,607 |
2010 |  |  | 65,997 |  |  | 107,139 |  |  | 173,136 |
2011 |  |  | 49,055 |  |  | 63,931 |  |  | 112,986 |
2014 –2017 |  |  | 23,450 |  |  | - |  |  | 23,450 |
|  |  | 252,624 |  |  | 364,466 |  |  | 617,090 |
Disclosure of detailed information reconciliation of income tax rate [Text Block] | For the years ended December 31, 2017, 2016 and 2015, the income tax expense recorded differs from the result of applying the legal rate to the Company’s profit before income tax, as detailed below:
|  | 2017 |  | 2016 |  | 2015 |
|  | US$(000) |  | US$(000) |  | US$(000) |
Profit before income tax |  |  | 835,924 |  |  | 603,989 |  |  | 79,530 |
Income tax rate |  |  | 32 | % |  | 32 | % |  | 32 | %
Expected income tax expense |  |  | 267,496 |  |  | 193,276 |  |  | 25,450 |
Non - deductible expenses |  |  | 25,217 |  |  | 27,788 |  |  | 19,534 |
Royalty case |  |  | (12,029) |  |  | - |  |  | - |
Special mining tax and mining royalties |  |  | (21,704) |  |  | (12,084) |  |  | (4,672) |
Income tax rate change effect on deferred taxes for change in Peruvian tax law once the current Stability Contract expires (from 32% to 31.35%) |  |  | (1,632) |  |  | 13,850 |  |  | - |
Income tax true – ups |  |  | 10,210 |  |  | 1,677 |  |  | (6,082) |
Others |  |  | (4,125) |  |  | (1,913) |  |  | (3,047) |
Current and deferred income tax charges to results |  |  | 263,433 |  |  | 222,594 |  |  | 31,183 |
Mining taxes charged to results |  |  | 213,280 |  |  | 37,763 |  |  | 14,599 |
Supplementary retirement fund charged to results |  |  | 9,330 |  |  | 2,725 |  |  | 464 |
|  |  | 486,043 |  |  | 263,082 |  |  | 46,246 |
Effective income tax |  |  | 58.14 | % |  | 43.56 | % |  | 58.15 | %

X
- Definition The disclosure of deferred taxes. [Refer: Deferred tax liabilities; Deferred tax assets] + References No definition available. + Details
Name: | cik0001013131_DisclosureOfDetailedDeferredTaxesTextBlock
Namespace Prefix: | cik0001013131_
Data Type: | nonnum:textBlockItemType
Balance Type: | na
Period Type: | duration

X
- References No definition available. + Details
Name: | cik0001013131_DisclosureOfDetailedInformationAboutIncomeTaxProvisionTextBlock
Namespace Prefix: | cik0001013131_
Data Type: | nonnum:textBlockItemType
Balance Type: | na
Period Type: | duration

X
- Definition The disclosure of detailed information about other tax assessments. + References No definition available. + Details
Name: | cik0001013131_DisclosureOfDetailedInformationAboutOtherTaxAssesmentTextBlock
Namespace Prefix: | cik0001013131_
Data Type: | nonnum:textBlockItemType
Balance Type: | na
Period Type: | duration

X
- Definition The disclosure of detailed information of income tax years for review by tax authorities. + References No definition available. + Details
Name: | cik0001013131_DisclosureOfDetailedInformationIncomeTaxYearsToReviewTextBlock
Namespace Prefix: | cik0001013131_
Data Type: | nonnum:textBlockItemType
Balance Type: | na
Period Type: | duration

X
- References No definition available. + Details
Name: | cik0001013131_DisclosureOfDetailedInformationReconciliationOfIncomeTaxRateTextBlock
Namespace Prefix: | cik0001013131_
Data Type: | nonnum:textBlockItemType
Balance Type: | na
Period Type: | duration

X
- References No definition available. + Details
Name: | cik0001013131_DisclosureOfIncomeTaxExplanatoryLineItems
Namespace Prefix: | cik0001013131_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition The disclosure of reconciliation of accounting profit multiplied by applicable tax rates. + References No definition available. + Details
Name: | cik0001013131_DisclosureOfTaxExpenseReconciliationOfAccountingProfitMultipliedByApplicableTaxRatesTextBlock
Namespace Prefix: | cik0001013131_
Data Type: | nonnum:textBlockItemType
Balance Type: | na
Period Type: | duration

X
- Definition The disclosure of types of temporary differences, unused tax losses and unused tax credits. [Refer: Unused tax credits [member]; Unused tax losses [member]; Temporary differences [member]] + References No definition available. + Details
Name: | cik0001013131_DisclosureOfTemporaryDifferenceUnusedTaxLossesAndUnusedTaxCreditsExplanatory1TextBlock
Namespace Prefix: | cik0001013131_
Data Type: | nonnum:textBlockItemType
Balance Type: | na
Period Type: | duration

X
- Details
Name: | ifrs-full_SignificantInvestmentsInAssociatesAxis=cik0001013131_MineraYanacochaSrlAndSubsidiaryMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_SignificantInvestmentsInAssociatesAxis=cik0001013131_SociedadMineraElBrocalSaaMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |