XML 45 R65.htm IDEA: XBRL DOCUMENT
v3.20.1

MINING INTERESTS - Carrying amount (Details) - USD ($) $ in Millions | Dec. 31, 2019 | Dec. 31, 2018
--- | --- | ---
Mining Interests |  |
Property, plant and equipment | $ 1,928.0 | $ 1,853.4
New Afton |  |
Mining Interests |  |
Property, plant and equipment | 588.4 | 656.0
Cerro San Pedro |  |
Mining Interests |  |
Property, plant and equipment |  | 0.0
Rainy River |  |
Mining Interests |  |
Property, plant and equipment | 979.8 | 853.9
Blackwater |  |
Mining Interests |  |
Property, plant and equipment | 354.6 | 340.3
Other [Member] |  |
Mining Interests |  |
Property, plant and equipment | 5.2 | 3.2
Depletable [Member] |  |
Mining Interests |  |
Property, plant and equipment | 619.7 | 545.7
Depletable [Member] | New Afton |  |
Mining Interests |  |
Property, plant and equipment | 371.4 | 421.9
Depletable [Member] | Cerro San Pedro |  |
Mining Interests |  |
Property, plant and equipment |  | 0.0
Depletable [Member] | Rainy River |  |
Mining Interests |  |
Property, plant and equipment | 248.3 | 123.8
Depletable [Member] | Blackwater |  |
Mining Interests |  |
Property, plant and equipment | 0.0 | 0.0
Depletable [Member] | Other [Member] |  |
Mining Interests |  |
Property, plant and equipment | 0.0 | 0.0
Non-depletable [Member] |  |
Mining Interests |  |
Property, plant and equipment | 409.0 | 367.6
Non-depletable [Member] | New Afton |  |
Mining Interests |  |
Property, plant and equipment | 50.0 | 26.1
Non-depletable [Member] | Cerro San Pedro |  |
Mining Interests |  |
Property, plant and equipment |  | 0.0
Non-depletable [Member] | Rainy River |  |
Mining Interests |  |
Property, plant and equipment | 17.8 | 14.3
Non-depletable [Member] | Blackwater |  |
Mining Interests |  |
Property, plant and equipment | 340.1 | 326.1
Non-depletable [Member] | Other [Member] |  |
Mining Interests |  |
Property, plant and equipment | 1.1 | 1.1
Plant and Equipment [Member] |  |
Mining Interests |  |
Property, plant and equipment | 769.9 | 812.9
Plant and Equipment [Member] | New Afton |  |
Mining Interests |  |
Property, plant and equipment | 149.2 | 191.6
Plant and Equipment [Member] | Cerro San Pedro |  |
Mining Interests |  |
Property, plant and equipment |  | 0.0
Plant and Equipment [Member] | Rainy River |  |
Mining Interests |  |
Property, plant and equipment | 602.1 | 605.0
Plant and Equipment [Member] | Blackwater |  |
Mining Interests |  |
Property, plant and equipment | 14.5 | 14.2
Plant and Equipment [Member] | Other [Member] |  |
Mining Interests |  |
Property, plant and equipment | 4.1 | 2.1
Construction in Progress [Member] |  |
Mining Interests |  |
Property, plant and equipment | 129.4 | 127.2
Construction in Progress [Member] | New Afton |  |
Mining Interests |  |
Property, plant and equipment | 17.8 | 16.4
Construction in Progress [Member] | Cerro San Pedro |  |
Mining Interests |  |
Property, plant and equipment |  | 0.0
Construction in Progress [Member] | Rainy River |  |
Mining Interests |  |
Property, plant and equipment | 111.6 | 110.8
Construction in Progress [Member] | Blackwater |  |
Mining Interests |  |
Property, plant and equipment | 0.0 | 0.0
Construction in Progress [Member] | Other [Member] |  |
Mining Interests |  |
Property, plant and equipment | $ 0.0 | $ 0.0

X
- Definition The amount of tangible assets that: (a) are held for use in the production or supply of goods or services, for rental to others, or for administrative purposes; and (b) are expected to be used during more than one period. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 16 -IssueDate 2019-01-01 -Paragraph 73 -Subparagraph e -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=16&code=ifrs-tx-2019-en-r&anchor=para_73_e&doctype=Standard -URIDate 2019-03-27 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 1 -IssueDate 2019-01-01 -Paragraph 54 -Subparagraph a -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=1&code=ifrs-tx-2019-en-r&anchor=para_54_a&doctype=Standard -URIDate 2019-03-27 + Details
Name: | ifrs-full_PropertyPlantAndEquipment
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition . + References No definition available. + Details
Name: | ngd_MiningInterestsLineItems
Namespace Prefix: | ngd_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Details
Name: | ngd_MiningInterestBySiteAxis=ngd_NewAftonMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ngd_MiningInterestBySiteAxis=ngd_CerroSanPedroMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ngd_MiningInterestBySiteAxis=ngd_RainyRiverMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ngd_MiningInterestBySiteAxis=ngd_BlackwaterMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ngd_MiningInterestBySiteAxis=ngd_OtherMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_ClassesOfPropertyPlantAndEquipmentAxis=ngd_MiningPropertiesDepletableMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_ClassesOfPropertyPlantAndEquipmentAxis=ngd_MiningPropertiesNondepletableIncludingExplorationAndEvaluationMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_ClassesOfPropertyPlantAndEquipmentAxis=ngd_PlantAndEquipmentMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_ClassesOfPropertyPlantAndEquipmentAxis=ifrs-full_ConstructionInProgressMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |