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Face amount per share of no-par value common stock.

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Amount of cash inflow from exercise of option under share-based payment arrangement.

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Gross number of share options (or share units) granted during the period.

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Per share or per unit amount of equity securities issued.

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SHARE CAPITAL - Additional Information (Details)		3 Months Ended		6 Months Ended			12 Months Ended
SHARE CAPITAL - Additional Information (Details)	Jan. 28, 2026 USD ($) $ / shares shares	Jun. 30, 2026 CAD ($) $ / shares shares	Mar. 31, 2026 CAD ($) $ / shares shares	Jun. 30, 2026 USD ($) $ / shares shares	Jun. 30, 2026 $ / shares $ / shares	Jun. 30, 2025 USD ($) shares	Dec. 31, 2025 CAD ($) $ / shares shares	Jun. 30, 2026 CAD ($) shares	Dec. 31, 2025 $ / shares shares	Mar. 31, 2025 shares	Dec. 31, 2024 shares
SHARE CAPITAL
Share capital, unlimited shares authorized				Unlimited			Unlimited
Common stock, no par value (in dollars per share) \| $ / shares				$ 0	$ 0				$ 0
Common stock, shares, issued (in shares) \| shares								261,637,473	207,885,473
Common stock, shares, outstanding (in shares) \| shares								261,637,473	207,885,473
Share issuance \| $				$ 118,086,240		$ 3,932,994
Weighted average remaining outstanding (in years)				1 year 9 months 18 days
Unrecognized compensation expense \| $								$ 387,623
Weighted-average remaining period				1 year 4 months 24 days
Non-vested options \| shares								240,000	240,000
Allocated share-based compensation expense \| $				$ 865,942		$ 509,981
Share based compensation arrangement by share based payment award percentage of shares authorized								10.00%
Common stock
SHARE CAPITAL
Common stock, shares, issued (in shares) \| shares			261,637,473			207,885,473		261,637,473	207,885,473	207,885,473	199,693,442
Share issuance (in shares) \| shares				53,192,000		8,192,031
Share issuance \| $				$ 118,086,240		$ 3,932,994
Exercise of options (in shares) \| shares				560,000
Reallocation of contributed surplus \| $				$ 128,189
Stock Options
SHARE CAPITAL
Exercise of options (in shares) \| shares				560,000
Stock option granted (in shares) \| shares				240,000			240,000
Cancelled (in shares) \| shares							500,000
Non-vested options \| shares						240,000		240,000
Allocated share-based compensation expense \| $				$ 199,621		$ 172,547
Stock Options \| Common stock
SHARE CAPITAL
Exercise of options (in shares) \| shares				560,000
Total proceeds \| $				$ 267,795
Reallocation of contributed surplus \| $				$ 128,189
Deferred stock units (DSUs)
SHARE CAPITAL
Issued (in shares) \| shares				264,543		332,000
Allocated share-based compensation expense \| $				$ 666,321		$ 337,434
Plan 2006 \| Stock Options
SHARE CAPITAL
Share based compensation arrangement by share based payment award shares authorized percentage								10.00%
Plan 2006 \| Maximum \| Stock Options
SHARE CAPITAL
Maximum term of stock option plan				10 years
Deferred Share Unit Incentive Plan
SHARE CAPITAL
Issued (in shares) \| shares				264,543			332,000
Weighted average granted value per share (in dollars per share) \| $ / shares					$ 3.35		$ 1.25
Members Of Board \| Deferred Share Unit Incentive Plan
SHARE CAPITAL
Issued (in shares) \| shares			41,503
Weighted average granted value per share (in dollars per share) \| $ / shares			$ 3.44
Aggregate value \| $			$ 142,770
Members Of Board \| Deferred Share Unit Incentive Plan \| Non-Paulson Directors
SHARE CAPITAL
Weighted average granted value per share (in dollars per share) \| $ / shares							$ 1.25
Grant value per director \| $							$ 83,000
Aggregate value \| $							$ 415,000
Shares granted in period per director \| shares							66,400
Members Of Board \| Deferred Share Unit Incentive Plan \| Paulson
SHARE CAPITAL
Issued (in shares) \| shares							332,000
Non-Paulson Directors \| Deferred Share Unit Incentive Plan
SHARE CAPITAL
Grant value per director \| $		$ 120,330
Shares granted in period per director \| shares		36,135
Lead independent director \| Deferred Share Unit Incentive Plan
SHARE CAPITAL
Issued (in shares) \| shares		6,230
Aggregate value \| $		$ 20,743
Nonpaulson and Lead independent director \| Deferred Share Unit Incentive Plan
SHARE CAPITAL
Issued (in shares) \| shares		223,040
Weighted average granted value per share (in dollars per share) \| $ / shares		$ 3.33
Aggregate value \| $		$ 742,723
Public Offering
SHARE CAPITAL
Share issuance (in shares) \| shares	1,501,982			33,672,000
Share issuance \| $	$ 3,334,400			$ 74,751,840
Share price (in dollars per share) \| $ / shares	$ 2.22			$ 2.22	$ 2.22
Private Placement
SHARE CAPITAL
Share issuance (in shares) \| shares				18,018,018
Share issuance \| $				$ 40,000,000
Share price (in dollars per share) \| $ / shares				$ 2.22	$ 2.22
Over-Allotment
SHARE CAPITAL
Share issuance (in shares) \| shares				4,392,000
Location, Statement of Income, Balance [Axis]: us-gaap:LaborAndRelatedExpense \| Stock Options
SHARE CAPITAL
Allocated share-based compensation expense \| $				$ 174,669		73,735
Location, Statement of Income, Balance [Axis]: thm:ConsultingFees
SHARE CAPITAL
Allocated share-based compensation expense \| $				678,797		430,979
Location, Statement of Income, Balance [Axis]: thm:ConsultingFees \| Stock Options
SHARE CAPITAL
Allocated share-based compensation expense \| $				12,476		93,545
Location, Statement of Income, Balance [Axis]: thm:ConsultingFees \| Deferred stock units (DSUs)
SHARE CAPITAL
Allocated share-based compensation expense \| $				666,321		337,434
Location, Statement of Income, Balance [Axis]: thm:InvestorRelationsExpenses \| Stock Options
SHARE CAPITAL
Allocated share-based compensation expense \| $				$ 12,476		$ 5,267