Addition to mineral properties.

No definition available.

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- Definition

Represents the amount of deferred income tax recovery on impairment of mineral properties.

+ References

No definition available.

+ Details

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- Definition

Represents the amount of amortization expense related to the mineral property interests and capitalized asset retirement costs.

+ References

No definition available.

+ Details

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- Definition

Mineral Property Interests [Line Items]

+ References

No definition available.

+ Details

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- Definition

The total cash outflow from the purchase of mining and mining related assets during the period. Includes purchase price at closing and a deferred payment.

+ References

No definition available.

+ Details

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- Definition

The required payment of gross revenue less allowable deductions to the tiered net smelter return royalty (the “Royalty”) on the El Gallo 1 Mine.

+ References

No definition available.

+ Details

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- Definition

The eventually reduced percentage of required payment of gross revenue less allowable deductions to the tiered net smelter return royalty (the “Royalty”) on the El Gallo 1 Mine.

+ References

No definition available.

+ Details

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- Definition

Amount of write-down of assets recognized in the income statement. Includes, but is not limited to, losses from tangible assets, intangible assets and goodwill.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section 45
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=68055307&loc=d3e2420-110228

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3602-108585

+ Details

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- Definition

Mineral properties, net of adjustments.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 932
-SubTopic 360
-Section 25
-Paragraph 7
-URI http://asc.fasb.org/extlink&oid=96866604&loc=d3e64895-109465

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6391035&loc=d3e2868-110229

+ Details

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- Definition

The cash outflow from the purchase of mining and mining related assets during the period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 13
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3213-108585

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- Details

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- Details

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MINERAL PROPERTY INTEREST - Mineral Property Interests (Details) - USD ($) $ in Thousands			3 Months Ended		12 Months Ended
	Jun. 30, 2018	Apr. 19, 2016	Dec. 31, 2015	Jun. 30, 2015	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Aug. 25, 2017
Mineral Property Interests
Mineral property interests					$ 293,437	$ 242,640
Payments to Acquire Mining Assets					3,492	5,985
Additional to mineral properties					3,300	0
Impairment charges					711		$ 50,600
Amortization of mineral property interests and asset retirement obligations					3,198	2,413	1,288
Nevada
Mineral Property Interests
Impairment charges			$ 7,500	$ 29,700
Deferred Income Tax on Impairment of Mineral Properties			2,200	$ 10,400
Black Fox
Mineral Property Interests
Mineral property interests					11,364
Amortization of mineral property interests and asset retirement obligations					900	0	0
Lexam VG Gold
Mineral Property Interests
Mineral property interests					41,595
Los Azules Copper Project
Mineral Property Interests
Mineral property interests					191,490	191,490
Impairment charges			11,400
Deferred Income Tax on Impairment of Mineral Properties			1,300
Gold Bar Complex \| Nevada
Mineral Property Interests
Impairment charges							20,847
Tonkin Properties
Mineral Property Interests
Mineral property interests					4,833	4,833
Tonkin Properties \| Nevada
Mineral Property Interests
Impairment charges							14,939
El Gallo 1 mine
Mineral Property Interests
Mineral property interests					6,246	8,545
Amortization of mineral property interests and asset retirement obligations					2,300	2,400	1,300
El Gallo 2 project
Mineral Property Interests
Mineral property interests					5,807	5,807
Impairment charges			$ 2,000		700
North Battle Mountain Complex Located in Nevada, United States \| Nevada
Mineral Property Interests
Impairment charges							1,443
North Battle Mountain Properties Located In Nevada United States
Mineral Property Interests
Mineral property interests					785	785
Gold Bar project
Mineral Property Interests
Mineral property interests					31,317	31,180
Royalty
Mineral Property Interests
Required payment of gross revenue less allowable deductions to the tiered net smelter return royalty on the El Gallo 1 Mine (as a percent)		3.50%
Eventually reduced percentage of required payment		1
Total purchase price at closing		$ 6,300
Payments to Acquire Mining Assets	$ 1,000	5,300
Royalty \| Other Noncurrent Liabilities [Member]
Mineral Property Interests
Payments to Acquire Mining Assets					1,000
Royalty \| El Gallo 1 mine
Mineral Property Interests
Additional to mineral properties		5,100
Royalty \| El Gallo 2 project
Mineral Property Interests
Additional to mineral properties		$ 1,200
Black Fox
Mineral Property Interests
Mineral property interests								$ 8,954
Argentina \| Los Azules Copper Project
Mineral Property Interests
Impairment charges							11,399
Mexico
Mineral Property Interests
Impairment charges					$ 711
Mexico \| Property, Plant and Equipment
Mineral Property Interests
Impairment charges							$ 1,972
Mexico \| Nevada And Argentina
Mineral Property Interests
Impairment charges						$ 50,600