XML 203 R189.htm IDEA: XBRL DOCUMENT
v3.19.1

Exploration in operating units (Details) - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2018 | Dec. 31, 2017 | Dec. 31, 2016
Disclosure Of Exploration In Operating Units [Line Items] |  |  |
Beginning balance of finished goods and products in process, net of depreciation and amortization | $ 5,157 | $ 5,309 | $ 3,106
Expense arising from exploration for and evaluation of Operating units | 90,343 | 94,928 | 96,149
Final balance of products in process and finished goods, net of depreciation and amortization | (2,837) | 5,157 | 5,309
Exploration in operating units | 90,343 | 94,928 | 96,149
Services provided by third parties |  |  |
Disclosure Of Exploration In Operating Units [Line Items] |  |  |
Expense arising from exploration for and evaluation of Operating units | 71,927 | 79,837 | 81,464
Consumption of materials and supplies |  |  |
Disclosure Of Exploration In Operating Units [Line Items] |  |  |
Expense arising from exploration for and evaluation of Operating units | 8,605 | 8,236 | 12,685
Direct labor |  |  |
Disclosure Of Exploration In Operating Units [Line Items] |  |  |
Expense arising from exploration for and evaluation of Operating units | 2,446 | 2,373 | 1,974
Rentals |  |  |
Disclosure Of Exploration In Operating Units [Line Items] |  |  |
Expense arising from exploration for and evaluation of Operating units | 2,072 | 1,527 | 1,608
Electricity and water |  |  |
Disclosure Of Exploration In Operating Units [Line Items] |  |  |
Expense arising from exploration for and evaluation of Operating units | 1,524 | 1,328 | 21
Maintenance and repair |  |  |
Disclosure Of Exploration In Operating Units [Line Items] |  |  |
Expense arising from exploration for and evaluation of Operating units | 450 | 100 | 62
Transport |  |  |
Disclosure Of Exploration In Operating Units [Line Items] |  |  |
Expense arising from exploration for and evaluation of Operating units | 192 | 587 | 317
Depreciation and amortization |  |  |
Disclosure Of Exploration In Operating Units [Line Items] |  |  |
Expense arising from exploration for and evaluation of Operating units | 23 | 0 | 0
Other |  |  |
Disclosure Of Exploration In Operating Units [Line Items] |  |  |
Expense arising from exploration for and evaluation of Operating units | $ 784 | $ 109 | $ 379

X
- Definition Balance of Products In Process And Finished Goods + References No definition available. + Details
Name: | cik0001013131_BalanceOfProductsInProcessAndFinishedGoods
Namespace Prefix: | cik0001013131_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- References No definition available. + Details
Name: | cik0001013131_DisclosureOfExplorationInOperatingUnitsLineItems
Namespace Prefix: | cik0001013131_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition The amount of expense arising from the search for mineral resources of operating units. + References No definition available. + Details
Name: | cik0001013131_ExpenseArisingFromExplorationForAndEvaluationOfOperatingUnits
Namespace Prefix: | cik0001013131_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition represents exploration In operating units net + References No definition available. + Details
Name: | cik0001013131_ExplorationInOperatingUnitsNet
Namespace Prefix: | cik0001013131_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Details
Name: | cik0001013131_ExpensesByNatureAxis=cik0001013131_ServicesProvidedByThirdPartiesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | cik0001013131_ExpensesByNatureAxis=cik0001013131_ConsumptionOfMaterialsAndSuppliesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | cik0001013131_ExpensesByNatureAxis=cik0001013131_DirectLaborMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | cik0001013131_ExpensesByNatureAxis=cik0001013131_RentalsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | cik0001013131_ExpensesByNatureAxis=cik0001013131_ElectricityAndWaterMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | cik0001013131_ExpensesByNatureAxis=cik0001013131_MaintenanceAndRepairMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | cik0001013131_ExpensesByNatureAxis=cik0001013131_TransportMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | cik0001013131_ExpensesByNatureAxis=cik0001013131_DepreciationAndAmortizationMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | cik0001013131_ExpensesByNatureAxis=cik0001013131_OtherMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |