The weighted average of interest and other costs that an entity incurs in connection with the borrowing of funds applicable to the borrowings of the entity that are outstanding during the period, other than borrowings made specifically for the purpose of obtaining a qualifying asset. [Refer: Weighted average [member]; Borrowings]

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 23
-IssueDate 2017-01-01
-Paragraph 26
-Subparagraph b
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=23&date=2017-03-01&anchor=para_26_b&doctype=Standard
-URIDate 2017-03-09

+ Details

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Namespace Prefix:	ifrs-full_
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Balance Type:	na
Period Type:	duration

- Definition

The amount of interest costs that an entity incurs in connection with the borrowing of funds that are directly attributable to the acquisition, construction or production of a qualifying asset and which form part of the cost of that asset.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name IAS
-Number 1
-IssueDate 2017-01-01
-Paragraph 112
-Subparagraph c
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=1&date=2017-03-01&anchor=para_112_c&doctype=Standard
-URIDate 2017-03-09

+ Details

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Namespace Prefix:	ifrs-full_
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Balance Type:	na
Period Type:	duration

- Definition

The decrease in El Morro stream resulting from disposals.

+ References

No definition available.

+ Details

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Namespace Prefix:	ngd_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The gain on the disposal of El Morro stream.

+ References

No definition available.

+ Details

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Namespace Prefix:	ngd_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

It represents the amounts transferred out of construction in progress to inventories upon reaching commercial production.

+ References

No definition available.

+ Details

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Namespace Prefix:	ngd_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- References

No definition available.

+ Details

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- Definition

Represent the amount of proceeds from sale of El Morro stream.

+ References

No definition available.

+ Details

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Namespace Prefix:	ngd_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Details

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MINING INTERESTS (Details Textual) - USD ($) $ in Millions	1 Months Ended		12 Months Ended
MINING INTERESTS (Details Textual) - USD ($) $ in Millions	Nov. 30, 2017	Feb. 28, 2017	Dec. 31, 2017	Dec. 31, 2016
Mining Interests [Line Items]
Interest costs capitalised			$ 51.3	$ 49.4
Capitalisation rate of borrowing costs eligible for capitalisation			5.44%	6.70%
Gains on Disposal of El Morro Stream		$ 33.0	$ 33.0	$ 0.0
Proceeds from Sale of El Morro stream		65.0
Disposals El Morro Stream		$ 32.0
Gross carrying amount [member]
Mining Interests [Line Items]
Increase decrease through transfers from construction in progress, inventories	$ 20.4