Addition to mineral properties.

No definition available.

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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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Balance Type:	credit
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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://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3602-108585

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section 45
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=109226348&loc=d3e2420-110228

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Balance Type:	debit
Period Type:	duration

- Definition

Mineral properties, net of adjustments.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-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

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-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6391035&loc=d3e2868-110229

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 13
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-URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3213-108585

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- Details

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- Details

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- Details

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- Details

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- Details

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- Details

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- Details

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- Details

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MINERAL PROPERTY INTERESTS - Mineral Property Interests (Details) - USD ($) $ in Thousands			12 Months Ended
	Jun. 30, 2018	Apr. 19, 2016	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Aug. 25, 2017
Mineral Property Interests
Payments to aquire mineral propety interests			$ 18,983	$ 3,492	$ 5,985
Additional to mineral properties			19,400	3,300
Impairment charges				711
Mineral property interests			309,145	293,437
Amortization of mineral property interests and asset retirement obligations			7,256	3,198	2,413
Black Fox
Mineral Property Interests
Mineral property interests			16,365	11,364
Black Fox \| Production costs applicable to sales
Mineral Property Interests
Amortization of mineral property interests and asset retirement obligations			5,100		0
Lexam VG Gold
Mineral Property Interests
Mineral property interests			41,595	41,595
Los Azules Copper Project
Mineral Property Interests
Mineral property interests			191,490	191,490
Tonkin Properties
Mineral Property Interests
Mineral property interests			4,833	4,833
El Gallo 1 mine \| Production costs applicable to sales
Mineral Property Interests
Amortization of mineral property interests and asset retirement obligations			2,100	2,300	$ 2,400
El Gallo Project
Mineral Property Interests
Mineral property interests			4,139	6,246
Fenix Project Properties
Mineral Property Interests
Mineral property interests			5,807	5,807
El Gallo 2 project
Mineral Property Interests
Impairment charges				700
Battle Mountain Complex Located In Nevada United States
Mineral Property Interests
Mineral property interests			785	785
Gold Bar project
Mineral Property Interests
Mineral property interests			$ 44,131	31,317
Royalty
Mineral Property Interests
Total purchase price at closing		$ 6,300
Payments to aquire mineral propety interests	$ 1,000	5,300
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
Black Fox \| Production costs applicable to sales
Mineral Property Interests
Amortization of mineral property interests and asset retirement obligations				900
Mexico
Mineral Property Interests
Impairment charges				$ 711