Condensed Consolidated Statements of Changes in Equity - USD ($) $ in Thousands	Common Shares 2025 Registered Direct Offering	Common Shares 2024 Registered Direct Offering	Common Shares Class A Warrants	Common Shares Class B Warrants	Common Shares	Additional Paid in Capital 2025 Registered Direct Offering	Additional Paid in Capital 2024 Registered Direct Offering	Additional Paid in Capital Class A Warrants	Additional Paid in Capital Class B Warrants	Additional Paid in Capital	Accumulated Other Comprehensive Loss	Deficit	2025 Registered Direct Offering	2024 Registered Direct Offering	Class A Warrants	Class B Warrants	Total
Balance at Dec. 31, 2023					$ 438,239					$ 122,797	$ (1,216)	$ (548,902)					$ 10,918
Balance (in shares) at Dec. 31, 2023					306,558,710
Issuance of shares and warrants under, net of expenses (Notes 10, 12)					$ 7,447					1,553							9,000
Issuance of shares and warrants under, net of expenses (Notes 10, 12) (in shares)					4,500,000
Shares issued from ATM (Note 11)					$ 2,587												2,587
Shares issued from ATM (Note 11) (in shares)					1,634,588
Exercise of stock options (Note 13)					$ 1,761					(1,352)							409
Exercise of stock options (Note 13) (in shares)					631,052
Conversion of restricted share units, net of shares withheld for taxes (Note 13)					$ 10,485					(10,485)
Conversion of restricted share units, net of shares withheld for taxes (Note 13) (in shares)					8,890,139
Share purchase under Employee Share Purchase Plan (Note 13)					$ 54					(30)							24
Share purchase under Employee Share Purchase Plan (Note 13) (in shares)					27,394
Share-based compensation and expenses settled with equity (Note 13)										12,817							12,817
Loss for the period												(45,362)					(45,362)
Balance at Jun. 30, 2024					$ 460,573					125,300	(1,216)	(594,264)					(9,607)
Balance (in shares) at Jun. 30, 2024					322,241,883
Balance at Dec. 31, 2023					$ 438,239					122,797	(1,216)	(548,902)					10,918
Balance (in shares) at Dec. 31, 2023					306,558,710
Balance at Dec. 31, 2024					$ 477,217					138,303	(1,203)	(631,435)					(17,118)
Balance (in shares) at Dec. 31, 2024					340,708,460
Balance at Mar. 31, 2024					$ 454,431					122,691	(1,216)	(574,096)					1,810
Balance (in shares) at Mar. 31, 2024					318,291,383
Shares issued from ATM (Note 11)					$ 2,587												2,587
Shares issued from ATM (Note 11) (in shares)					1,634,588
Exercise of stock options (Note 13)					$ 1,617					(1,398)							219
Exercise of stock options (Note 13) (in shares)					511,052
Conversion of restricted share units, net of shares withheld for taxes (Note 13)					$ 1,884					(1,884)
Conversion of restricted share units, net of shares withheld for taxes (Note 13) (in shares)					1,777,466
Share purchase under Employee Share Purchase Plan (Note 13)					$ 54					(30)							24
Share purchase under Employee Share Purchase Plan (Note 13) (in shares)					27,394
Share-based compensation and expenses settled with equity (Note 13)										5,921							5,921
Loss for the period												(20,168)					(20,168)
Balance at Jun. 30, 2024					$ 460,573					125,300	(1,216)	(594,264)					(9,607)
Balance (in shares) at Jun. 30, 2024					322,241,883
Balance at Dec. 31, 2024					$ 477,217					138,303	(1,203)	(631,435)					(17,118)
Balance (in shares) at Dec. 31, 2024					340,708,460
Issuance of shares and warrants to Korea Zinc, net of expenses (Notes 10, 12)					$ 71,686					13,432							85,118
Issuance of shares and warrants to Korea Zinc, net of expenses (Notes 10, 12) (in shares)					19,623,376
Issuance of shares and warrants under, net of expenses (Notes 10, 12)	$ 17,640	$ 2,237				$ 12,087	$ 2,763						$ 29,727	$ 5,000
Issuance of shares and warrants under, net of expenses (Notes 10, 12) (in shares)	9,000,000	5,000,000
Shares issued from ATM (Note 11)					$ 14,784												14,784
Shares issued from ATM (Note 11) (in shares)					7,542,996
Exercise of warrant (Note 12)			$ 724	$ 6,451				$ 3,053	$ (3,801)						$ 3,777	$ 2,650
Exercise of warrant (Note 12) (in shares)			250,000	4,833,096
Exercise of stock options (Note 13)					$ 1,453					(991)							462
Exercise of stock options (Note 13) (in shares)					712,124
Conversion of restricted share units, net of shares withheld for taxes (Note 13)					$ 14,042					(14,042)
Conversion of restricted share units, net of shares withheld for taxes (Note 13) (in shares)					9,472,733
Share purchase under Employee Share Purchase Plan (Note 13)					$ 12					(2)							10
Share purchase under Employee Share Purchase Plan (Note 13) (in shares)					12,533
Nauru Warrant Cost (Note 12)										33,079							33,079
Share-based compensation and expenses settled with equity (Note 13)										19,300							19,300
Loss for the period												(94,929)					(94,929)
Balance at Jun. 30, 2025					$ 606,246					203,181	(1,203)	(726,364)					81,860
Balance (in shares) at Jun. 30, 2025					397,155,318
Balance at Mar. 31, 2025					$ 495,804					140,656	(1,203)	(652,023)					(16,766)
Balance (in shares) at Mar. 31, 2025					356,617,022
Issuance of shares and warrants to Korea Zinc, net of expenses (Notes 10, 12)					$ 71,686					13,432							85,118
Issuance of shares and warrants to Korea Zinc, net of expenses (Notes 10, 12) (in shares)					19,623,376
Issuance of shares and warrants under, net of expenses (Notes 10, 12)					$ 17,640					12,087							29,727
Issuance of shares and warrants under, net of expenses (Notes 10, 12) (in shares)					9,000,000								9,000,000
Shares issued from ATM (Note 11)					$ 9,222												9,222
Shares issued from ATM (Note 11) (in shares)					4,567,770
Exercise of warrant (Note 12)			$ 724	$ 6,451				$ 3,053	$ (3,801)						$ 3,777	$ 2,650
Exercise of warrant (Note 12) (in shares)			250,000	4,833,096
Exercise of stock options (Note 13)					$ 1,453					(991)							462
Exercise of stock options (Note 13) (in shares)					712,124
Conversion of restricted share units, net of shares withheld for taxes (Note 13)					$ 3,254					(3,254)
Conversion of restricted share units, net of shares withheld for taxes (Note 13) (in shares)					1,539,397
Share purchase under Employee Share Purchase Plan (Note 13)					$ 12					(2)							10
Share purchase under Employee Share Purchase Plan (Note 13) (in shares)					12,533
Nauru Warrant Cost (Note 12)										33,079							33,079
Share-based compensation and expenses settled with equity (Note 13)										8,922							8,922
Loss for the period												(74,341)					(74,341)
Balance at Jun. 30, 2025					$ 606,246					$ 203,181	$ (1,203)	$ (726,364)					$ 81,860
Balance (in shares) at Jun. 30, 2025					397,155,318