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Commitments and contingencies (Details Textual)
 1 Months Ended 12 Months Ended
Jan. 02, 2014
Jun. 23, 2004
Dec. 31, 2003
Dec. 31, 2002
Dec. 31, 2018
USD ($)
Dec. 31, 2018
PEN (S/)
Jan. 18, 2019
USD ($)
Dec. 31, 2018
PEN (S/)
Dec. 31, 2017
USD ($)
Dec. 02, 2009
USD ($)
Disclosure of Commitments and contingencies [Line Items]                    
Description of material leasing arrangements by lessor classified as operating lease         The Group has entered into operating leases on its administrative offices in Lima located in Las Begonias Street N°415, San Isidro, Lima, Peru, with a lease term of 10 years since the year 2013. The Group has the option to lease the assets for two additional term of 5 years each. The Group has entered into operating leases on its administrative offices in Lima located in Las Begonias Street N°415, San Isidro, Lima, Peru, with a lease term of 10 years since the year 2013. The Group has the option to lease the assets for two additional term of 5 years each.        
Estimated financial effect of contingent liabilities         $ 2,900,000       $ 1,100,000  
Withholding tax, New Tax Rate         30.00% 30.00%        
Withholding tax, Old Tax Rate         12.00% 12.00%        
Loss contingencies, laws affected         The alleged OEFA violations currently range from zero to 40,300 tax units and the Autoridad Nacional del Agua alleged violations range from zero to 10 tax units, being each tax unit equivalent to approximately US$1,260 based on current exchange rates. The alleged OEFA violations currently range from zero to 40,300 tax units and the Autoridad Nacional del Agua alleged violations range from zero to 10 tax units, being each tax unit equivalent to approximately US$1,260 based on current exchange rates.        
Withholding tax rate     12.00% 30.00%            
Income tax contingencies,amount         $ 3,500,000     S/ 12,000,000    
Payment to acquire contractual positions in mining concession agreements         $ 29,000,000          
Minera Yanacocha SRL and subsidiary [member]                    
Disclosure of Commitments and contingencies [Line Items]                    
Loss contingencies, laws affected         The alleged OEFA violations currently range from zero to 40,300 tax units and the water authority alleged violations range from zero to 10 tax units, being each tax unit equivalent to approximately US$1,260 based on current exchange rates. The alleged OEFA violations currently range from zero to 40,300 tax units and the water authority alleged violations range from zero to 10 tax units, being each tax unit equivalent to approximately US$1,260 based on current exchange rates.        
Provisional liability             $ 83,000,000      
Minera Yanacocha SRL and subsidiary [member] | Los Tapados S.A [Member]                    
Disclosure of Commitments and contingencies [Line Items]                    
Royalty rate on net sales         3.00% 3.00%        
Yanacocha [Member]                    
Disclosure of Commitments and contingencies [Line Items]                    
Provisional liability         $ 84,000,000          
Empresa de Generacion Huanza S.A. [Member]                    
Disclosure of Commitments and contingencies [Line Items]                    
Finance lease liabilities                   $ 119,000,000
Unrecognized Depreciation expense         $ 8,148,000 S/ 27,532,000        
San Jose Reservoir Trust [Member]                    
Disclosure of Commitments and contingencies [Line Items]                    
Outstanding commitments made by entity, related party transactions                 $ 6,321,000  
Sindicato Minero de Orcopampa [Member]                    
Disclosure of Commitments and contingencies [Line Items]                    
Lease concession expense, Percent         10.00% 10.00%        
S.M.R.L. Chaupiloma Dos de Cajamarca [Member] | Minera Yanacocha SRL and subsidiary [member]                    
Disclosure of Commitments and contingencies [Line Items]                    
Royalty rate on net sales         3.00% 3.00%        
Cerro Verde [Member] | Bottom of range [member]                    
Disclosure of Commitments and contingencies [Line Items]                    
Royalty rate on net sales   1.00%                
Cerro Verde [Member] | Top of range [member]                    
Disclosure of Commitments and contingencies [Line Items]                    
Royalty rate on net sales   3.00%                
Cerro Verde [Member] | New guarantee contract [Member] | Bottom of range [member]                    
Disclosure of Commitments and contingencies [Line Items]                    
Royalty rate on net sales 1.00%                  
Cerro Verde [Member] | New guarantee contract [Member] | Top of range [member]                    
Disclosure of Commitments and contingencies [Line Items]                    
Royalty rate on net sales 12.00%