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Inventory, net (Details) - USD ($)
$ in Thousands
 12 Months Ended
Dec. 31, 2017
Dec. 31, 2016
Disclosure of inventory net [Line Items]    
Finished goods $ 6,151 $ 12,763
Products in process 56,190 66,651
Spare parts and supplies 84,787 63,946
Provision for impairment of value of inventory (b) (11,603) (8,386)
Inventory gross 147,128 143,360
Finished goods [Abstract]    
Current inventories 132,287 120,947
Inventories, net 3,238 14,027
Inventories 135,525 134,974
Minera Yanacocha SRL and subsidiary [Member]    
Disclosure of inventory net [Line Items]    
Inventory gross 77,722 76,570
Allowance for obsolescence of materials and supplies (7,076) (5,272)
Finished goods [Abstract]    
Inventories 70,646 71,298
Minera Yanacocha SRL and subsidiary [Member] | Precious metals [Member]    
Disclosure of inventory net [Line Items]    
Inventory gross 15,446 15,012
Minera Yanacocha SRL and subsidiary [Member] | Leach in circuit [Member]    
Disclosure of inventory net [Line Items]    
Inventory gross 8,057 6,378
Minera Yanacocha SRL and subsidiary [Member] | Mill in circuit [Member]    
Disclosure of inventory net [Line Items]    
Inventory gross 2,048 2,493
Minera Yanacocha SRL and subsidiary [Member] | Materials and supplies [Member]    
Disclosure of inventory net [Line Items]    
Inventory gross 52,171 52,687
Sociedad Minera Cerro Verde S.A.A. [Member]    
Disclosure of inventory net [Line Items]    
Products in process [1] 148,928 148,178
Finished goods [Abstract]    
Copper cathode 4,032 8,220
Copper concentrate 18,068 15,073
Molybdenum concentrate 1,896 2,763
Less: Provision for obsolescence of materials and supplies (1,237) (303)
Current inventories 445,626 425,566
Inventories, net [1] 248,452 300,614
Inventories 694,078 726,180
Materials and supplies $ 273,939 $ 251,635
[1] Work-in-process 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.