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Area of land held.

No definition available.

Name:	us-gaap_AreaOfLand
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Data Type:	dtr-types:areaItemType
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The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 323
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (a)(1)
-URI https://asc.fasb.org/extlink&oid=114001798&loc=d3e33918-111571

Name:	us-gaap_EquityMethodInvestmentOwnershipPercentage
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Data Type:	dtr-types:percentItemType
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Amount of gain (loss) on sale or disposal of property, plant and equipment assets, including oil and gas property and timber property.

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 https://asc.fasb.org/extlink&oid=126954810&loc=d3e3602-108585

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Mineral properties, net of adjustments.

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 https://asc.fasb.org/extlink&oid=96866604&loc=d3e64895-109465

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-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section 50
-Paragraph 1
-URI https://asc.fasb.org/extlink&oid=6391035&loc=d3e2868-110229

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The cash inflow from the sale of long-lived, physical assets that are used in the normal conduct of business to produce goods and services and not intended for resale.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 12
-Subparagraph (c)
-URI https://asc.fasb.org/extlink&oid=126954810&loc=d3e3179-108585

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This element represents the carrying value, net of accumulated deprecation, as of the date of the statement of financial position of a property sold during the reporting period, but which sale is accounted for under the deposit method and, therefore, which property continues to be included in the statement of financial position.

Reference 1: http://fasb.org/us-gaap/role/ref/otherTransitionRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
-SubTopic 20
-Section 55
-Paragraph 17
-URI https://asc.fasb.org/extlink&oid=126906489&loc=d3e6831-110236

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Percentage of subsidiary's or equity investee's stock owned by parent company after stock transaction.

No definition available.

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Data Type:	dtr-types:percentItemType
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Period Type:	duration

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Name:	us-gaap_PropertyPlantAndEquipmentByTypeAxis=MLYF_TamiMosiPropertyMember
Namespace Prefix:
Data Type:	na
Balance Type:
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Name:	srt_StatementGeographicalAxis=MLYF_WhitePineCountyMember
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Data Type:	na
Balance Type:
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Name:	srt_StatementGeographicalAxis=MLYF_MoorMiningDistrictMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	srt_ProductOrServiceAxis=MLYF_BeaverdellPropertyMember
Namespace Prefix:
Data Type:	na
Balance Type:
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