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Inventory, net (Tables) | 12 Months Ended
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Dec. 31, 2017
Disclosure of inventory net [Line Items] |
Disclosure of Detailed Information of Inventories [Text Block] | This caption is made up as follows:
|  | 2017 |  | 2016 |
|  | US$(000) |  | US$(000) |
Finished goods |  |  | 6,151 |  |  | 12,763 |
Products in process |  |  | 56,190 |  |  | 66,651 |
Spare parts and supplies |  |  | 84,787 |  |  | 63,946 |
|  |  | 147,128 |  |  | 143,360 |
Provision for impairment of value of inventory (b) |  |  | (11,603) |  |  | (8,386) |
|  |  | 135,525 |  |  | 134,974 |
Classification by use: |  |  |  |  |  |  |
Current portion |  |  | 132,287 |  |  | 120,947 |
Non-current portion |  |  | 3,238 |  |  | 14,027 |
|  |  | 135,525 |  |  | 134,974 |
Disclosure Of Detailed Information About Mineral Deposits Inventory [Text Block] | Products in process include mineral deposits located in the Tajo Norte mining unit (El Brocal). The detail of this mineral as of December 31, 2017 and 2016 is presented below:
|  | 2017 |  | 2016 |
|  | US$(000) |  | DMT |  | US$(000) |  | DMT |
Mineral in stock piles |  |  | 7,173 |  |  | 463,746 |  |  | 16,793 |  |  | 1,085,696 |
Fresh mineral in plant |  |  | 11,983 |  |  | 835,613 |  |  | 1,248 |  |  | 74,260 |
Tail mineral |  |  | 279 |  |  | 30,110 |  |  | 203 |  |  | 24,629 |
|  |  | 19,435 |  |  | 1,329,469 |  |  | 18,244 |  |  | 1,184,585 |
Provision for impairment of value in mineral classified in process |  |  | (1,467) |  |  | - |  |  | (123) |  |  | - |
|  |  | 17,968 |  |  | 1,329,469 |  |  | 18,121 |  |  | 1,184,585 |
Classification by use: |  |  |  |  |  |  |  |  |  |  |  |  |
Current portion |  |  | 14,730 |  |  |  |  |  | 5,586 |  |  |  |
Non-current portion |  |  | 3,238 |  |  |  |  |  | 12,535 |  |  |  |
|  |  | 17,968 |  |  |  |  |  | 18,121 |  |  |  |
Disclosure of impairment of assets [text block] | The provision for impairment of value of inventory had the following movement during the years 2017, 2016 and 2015:
|  | 2017 |  | 2016 |  | 2015 |
|  | US$(000) |  | US$(000) |  | US$(000) |
Beginning balance |  |  | 8,386 |  |  | 20,472 |  |  | 7,735 |
Transfer from mining units held for sale |  |  | - |  |  | 1,448 |  |  | - |
Changes in provision for impairment of finished goods, (continuing operations), note 21(a) |  |  | 2,118 |  |  | (7,581) |  |  | 13,096 |
Changes in provision for impairment of finished goods (discontinued operations), note 1(e) |  |  | (1,345) |  |  | (706) |  |  | (1,474) |
Changes in provision for impairment of spare parts and supplies |  |  | 2,444 |  |  | (110) |  |  | 1,115 |
Reversal in provision for impairment of inventories |  |  | - |  |  | (5,137) |  |  | - |
Final balance |  |  | 11,603 |  |  | 8,386 |  |  | 20,472 |
Minera Yanacocha SRL and subsidiary [Member] |
Disclosure of inventory net [Line Items] |
Disclosure of Detailed Information of Inventories [Text Block] | This caption is made up as follows:
|  | 2017 |  | 2016 |
|  | US$(000) |  | US$(000) |
Precious metals |  |  | 15,446 |  |  | 15,012 |
Leach in-circuit |  |  | 8,057 |  |  | 6,378 |
Mill in-circuit |  |  | 2,048 |  |  | 2,493 |
Materials and supplies |  |  | 52,171 |  |  | 52,687 |
|  |  | 77,722 |  |  | 76,570 |
Allowance for obsolescence of materials and supplies (b) |  |  | (7,076) |  |  | (5,272) |
|  |  | 70,646 |  |  | 71,298 |
Disclosure of detailed information about allowance for obsolescence of material and supplies [Text Block] | The allowance for obsolescence of material and supplies had the following movement during the years 2017, 2016 and 2015:
|  | 2017 |  | 2016 |  | 2015 |
|  | US$(000) |  | US$(000) |  | US$(000) |
Opening balance |  |  | 5,272 |  |  | 5,881 |  |  | 4,832 |
Provision for impairment of materials and supplies |  |  | 2,896 |  |  | 3,104 |  |  | 5,060 |
Reversal of provision for impairment of materials and supplies |  |  | (1,092) |  |  | (3,713) |  |  | (4,011) |
Ending balance |  |  | 7,076 |  |  | 5,272 |  |  | 5,881 |
Sociedad Minera Cerro Verde S.A.A. [Member] |
Disclosure of inventory net [Line Items] |
Disclosure of Detailed Information of Inventories [Text Block] | This item is made up as follows:
|  | December 31, |  | December 31, |
|  | 2017 |  | 2016 |
|  | US$(000) |  | US$(000) |
Current |  |  |  |  |  |  |
Materials and supplies |  |  | 273,939 |  |  | 251,635 |
Work-in-process (WIP) (a) |  |  | 148,928 |  |  | 148,178 |
Finished goods: |  |  |  |  |  |  |
Copper concentrate |  |  | 18,068 |  |  | 15,073 |
Copper cathode |  |  | 4,032 |  |  | 8,220 |
Molybdenum concentrate |  |  | 1,896 |  |  | 2,763 |
Less: Provision for obsolescence of materials and supplies |  |  | (1,237) |  |  | (303) |
Total current |  |  | 445,626 |  |  | 425,566 |
Non-current |  |  |  |  |  |  |
Work-in-process (WIP) (a) |  |  | 248,452 |  |  | 300,614 |
Total inventories |  |  | 694,078 |  |  | 726,180 |
| (a) | 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.

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