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Inventories, net (Details) - USD ($)
$ in Thousands
 12 Months Ended
Dec. 31, 2019
Dec. 31, 2018
Dec. 31, 2017
Dec. 31, 2016
Inventory, net        
Finished goods $ 2,084 $ 7,715 $ 2,118  
Products in process [1] 47,652 73,796    
Spare parts and supplies 74,033 81,383    
Inventory gross 123,769 162,894    
Provision for impairment of value of inventory (25,402) (23,163)    
Finished goods [Abstract]        
Current inventories 97,973 135,919    
Inventories, net 394 3,812    
Inventories 98,367 139,731    
Minera Yanacocha SRL and subsidiary [Member]        
Inventory, net        
Inventory gross 60,343 62,042    
Allowance for obsolescence of materials and supplies (b) (6,098) (7,515) $ (7,076) $ (5,272)
Finished goods [Abstract]        
Current inventories 54,245 54,527    
Inventories 54,245 54,527    
Minera Yanacocha SRL and subsidiary [Member] | Precious metals [Member]        
Inventory, net        
Inventory gross 8,021 6,878    
Minera Yanacocha SRL and subsidiary [Member] | Leach in circuit [Member]        
Inventory, net        
Inventory gross 5,158 1,835    
Minera Yanacocha SRL and subsidiary [Member] | Mill in circuit [Member]        
Inventory, net        
Inventory gross 1,332 4,002    
Minera Yanacocha SRL and subsidiary [Member] | Materials and supplies [Member]        
Inventory, net        
Inventory gross 45,832 49,327    
Sociedad Minera Cerro Verde S.A.A. [Member]        
Inventory, net        
Products in process [2] 173,190 119,518    
Finished goods [Abstract]        
Copper cathode 6,321 8,035    
Copper concentrate 23,890 17,949    
Molybdenum concentrate 1,268 3,205    
Less: Provision for obsolescence of materials and supplies (507) (11)    
Current inventories 552,197 457,074    
Inventories, net [2] 255,123 286,375    
Inventories 807,320 743,449    
Materials and supplies $ 348,035 $ 308,378    
[1] Products in process include mainly to mineral in process of El Brocal for 1,592,905 Dried Metric Ton (DMT) amounting to US$31.2 million ( 2,254,874 DMT amounting to US$39.9 million as of December 31, 2018).
[2] WIP inventories represent mill and leach stockpiles, which contain higher grade ores (mill stockpiles) and medium and lower grade ores (leach stockpiles) that have been extracted from the open pit and are available for copper recovery. Based on the future mine plan production, the Company identifies the portion of inventory that is classified as current or long term. For mill stockpiles, recovery is through milling and concentrating. For leach stockpiles, recovery is through exposure to acidic solutions that dissolve copper and deliver it in a solution to extraction processing facilities.In fourth-quarter 2019, the Company changed its method of estimating the current portion of its leach and mill stockpiles and revised its December 31, 2018, balances to conform to the new methodology resulting in a US$30.5 million decrease in the current balance and increase in the long-term balance.