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v3.19.1

Provisions and contingent liabilities (Details Textual) - USD ($) | 12 Months Ended |  |
--- | --- | --- | ---
Dec. 31, 2018 | Dec. 31, 2017 | Dec. 31, 2016 | Dec. 31, 2013 | Jun. 27, 2016 | Dec. 31, 2015
Disclosure of provisions [Line Items] |  |  |  |  |  |
Provision for closure of mining units and exploration projects at future value | $ 280,300,000 |  |  |  |  |
Provision for closure of mining units and exploration projects | 225,877,000 | $ 200,183,000 | $ 206,462,000 |  |  |
Letter of credit | $ 119,700,000 | 109,600,000 |  |  |  |
Employee's profit share on annual taxable income | 8.00% |  |  |  |  |
Other provisions | $ 758,000 | 1,364,000 |  |  |  |
Notional amount | $ 275,000,000 | 275,000,000 |  |  | $ 275,000,000 |
Future value of non current provisions |  | $ 374,400,000 | $ 368,800,000 |  |  |
Annual risk free rate | 2.99% | 2.73% | 2.97% |  |  |
Increase (decrease) through transfers and other changes, other provisions | $ 32,000,000 |  |  |  |  |
Disputed mining royalties, noncurrent | 113,800,000 |  |  | $ 70,000,000 |  |
Net asset tax included in provisions | 19,600,000 | $ 9,800,000 |  |  |  |
Income and non-income tax contingencies included in other long-term liabilities | 6,200,000 | 11,400,000 |  |  |  |
Special Mining Tax |  |  |  | $ 50,800,000 |  |
Ministry of Energy and Mines [Member] |  |  |  |  |  |
Disclosure of provisions [Line Items] |  |  |  |  |  |
Notional amount | 42,700,000 |  |  |  |  |
Provision for remediation and mine closure [Member] |  |  |  |  |  |
Disclosure of provisions [Line Items] |  |  |  |  |  |
Non-current provisions | 131,900,000 | 156,900,000 | $ 153,300,000 |  |  |
Future value of non current provisions | 374,400,000 |  |  |  |  |
Increase (decrease) through transfers and other changes, other provisions | (32,017,000) | (3,710,000) | (16,091,000) |  |  |
La Joya [Member] | Irrigation Project [Member] | Provision for social commitments [Member] |  |  |  |  |  |
Disclosure of provisions [Line Items] |  |  |  |  |  |
Other provisions | 4,500,000 |  |  |  |  |
Alata-Congata Road [Member] | Repaving Project [Member] | Provision for social commitments [Member] |  |  |  |  |  |
Disclosure of provisions [Line Items] |  |  |  |  |  |
Other provisions | $ 5,400,000 |  |  |  |  |
Number of days of work [Member] |  |  |  |  |  |
Disclosure of provisions [Line Items] |  |  |  |  |  |
Percentage of distribution | 50.00% |  |  |  |  |
Annual salary levels [Member] |  |  |  |  |  |
Disclosure of provisions [Line Items] |  |  |  |  |  |
Percentage of distribution | 50.00% |  |  |  |  |
Minera Yanacocha SRL and subsidiary [Member] |  |  |  |  |  |
Disclosure of provisions [Line Items] |  |  |  |  |  |
Provision for closure of mining units and exploration projects | $ 1,294,464,000 | 1,234,731,000 | 1,012,888,000 |  |  | $ 578,959,000
Reclamation Expense | 16,284,000 | 124,124,000 | $ 78,494,000 |  |  |
Other provisions | 2,785,000 | 1,403,000 |  |  |  |
Minera Yanacocha SRL and subsidiary [Member] | Asset retirement and mine closure cost asset [member] |  |  |  |  |  |
Disclosure of provisions [Line Items] |  |  |  |  |  |
Additions other than through business combinations, property, plant and equipment | $ 27,200,000 | $ 97,000,000 |  |  |  |
Bottom of range [member] |  |  |  |  |  |
Disclosure of provisions [Line Items] |  |  |  |  |  |
Actuarial assumption of discount rates | 0.30% | 0.30% |  |  |  |
Top of range [member] |  |  |  |  |  |
Disclosure of provisions [Line Items] |  |  |  |  |  |
Discount rate used to reflect time value of money for provisions | 4.74% |  |  |  |  |
Actuarial assumption of discount rates | 2.90% | 2.90% |  |  |  |

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