Annual committed lease payments per acre.

No definition available.

Name:	thmg_AnnualCommittedLeasePaymentsPerAcre
Namespace Prefix:	thmg_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Annual committed lease payments per acre final seven-year period.

+ References

No definition available.

+ Details

Name:	thmg_AnnualCommittedLeasePaymentsPerAcreForFinalSevenYearPeriod
Namespace Prefix:	thmg_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Annual committed lease payments per acre for the first seven-year period.

+ References

No definition available.

+ Details

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

- Definition

Annual committed lease payments per acre for the second seven-year period.

+ References

No definition available.

+ Details

Name:	thmg_AnnualCommittedLeasePaymentsPerAcreForSecondSevenYearPeriod
Namespace Prefix:	thmg_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Annual committed lease payments per acre per original agreement for six year term.

+ References

No definition available.

+ Details

Name:	thmg_AnnualCommittedLeasePaymentsPerAcrePerOriginalAgreementForSixYearTerm
Namespace Prefix:	thmg_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Number of unpatented claims.

+ References

No definition available.

+ Details

Name:	thmg_NumberOfUnpatentedClaims
Namespace Prefix:	thmg_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

Area of land held.

+ References

No definition available.

+ Details

Name:	us-gaap_AreaOfLand
Namespace Prefix:	us-gaap_
Data Type:	dtr-types:areaItemType
Balance Type:	na
Period Type:	instant

- Definition

Term of lessee's operating lease renewal, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 842
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (a)(3)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478964/842-20-50-3

+ Details

Name:	us-gaap_LesseeOperatingLeaseRenewalTerm
Namespace Prefix:	us-gaap_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	instant

- Definition

Term of lessee's operating lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

+ Details

Name:	us-gaap_LesseeOperatingLeaseTermOfContract
Namespace Prefix:	us-gaap_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	instant

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Details

Name:	thmg_TargetAreaAxis=thmg_RonaldAcreeMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	thmg_TargetAreaAxis=thmg_WilliamAndNitaLowryMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	thmg_TargetAreaAxis=thmg_MichaelLowryMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	thmg_TargetAreaAxis=thmg_KevinAndJoLootensLivingTrustMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	thmg_TargetAreaAxis=thmg_LequericaAndSonsIncMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	thmg_TargetAreaAxis=thmg_TroutCreekMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	thmg_TargetAreaAxis=thmg_SouthMountainMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Mineral Interest Commitments (Narrative) (Details)				1 Months Ended	12 Months Ended
Mineral Interest Commitments (Narrative) (Details)	Oct. 24, 2025 USD ($)	Jun. 02, 2025 USD ($) a	Oct. 24, 2024 USD ($)	Aug. 22, 2025 USD ($) a	Dec. 31, 2025 a	Feb. 01, 2023	Oct. 24, 2008 a	Jun. 20, 2008 a
Other Commitments [Line Items]
Lease renewal term						24 months
Ronald Acree [Member]
Other Commitments [Line Items]
Area of land \| a								113
William And Nita Lowry [Member]
Other Commitments [Line Items]
Lease contract							6 years
Area of land \| a							376
Annual committed lease payments per acre per original agreement for six year term			$ 20
Michael Lowry [Member]
Other Commitments [Line Items]
Lease renewal term	21 years
Annual committed lease payments per acre for the first seven year period	$ 40
Annual committed lease payments per acre for the second seven year period	50
Annual committed lease payments per acre for the final seven year period	$ 60
Kevin and Jo Lootens Living Trust [Member]
Other Commitments [Line Items]
Lease contract		7 years
Area of land \| a		18
Annual committed lease payments per acre per original agreement for six year term		$ 30
Lease renewal term		10 years
Annual Committed Lease Payments Per Acre		$ 40
Lequerica & Sons, Inc. [Member]
Other Commitments [Line Items]
Area of land \| a				432
Annual committed lease payments per acre per original agreement for six year term				$ 30
Annual Committed Lease Payments Per Acre				$ 40
Trout Creek [Member]
Other Commitments [Line Items]
Area of land \| a					533
Number of unpatented claims					26
South Mountain [Member]
Other Commitments [Line Items]
Number of unpatented claims					34