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Joint Operations - Details of Significant Joint Operations (Detail) | 12 Months Ended
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Dec. 31, 2025
Disclosure of joint operations [line items] |  |
Category of business | Steel manufacturing and sales | [1]
Myanmar A-1/A-3 mine [member] |  |
Disclosure of joint operations [line items] |  |
Category of business | Mine development and gas production |
Ownership (%) | 51.00% |
Location | Myanmar |
Offshore Midstream [member] |  |
Disclosure of joint operations [line items] |  |
Category of business | Gas transportation facility |
Ownership (%) | 51.00% |
Location | Myanmar |
Mt. Thorley J/V [member] |  |
Disclosure of joint operations [line items] |  |
Category of business | Mine development |
Ownership (%) | 20.00% |
Location | Australia |
POSMAC J/V [member] |  |
Disclosure of joint operations [line items] |  |
Category of business | Mine development |
Ownership (%) | 20.00% |
Location | Australia |
[1] | As of December 31, 2025, the entities are classified as consolidated subsidiaries since the Company has control over the investees although the Company’s percentage of ownership is 50% or less, considering the structure of the entities’ Board of Directors and others.

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- Definition The description of the nature of the entity's operations and principal activities. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Note Effective 2027-01-01 -Name IFRS -Number 19 -IssueDate 2025-01-01 -Paragraph 141 -Subparagraph b -URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=19&code=ifrs-tx-2025-en-r&anchor=para_141_b&doctype=Standard -URIDate 2025-03-27 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Note Effective 2027-01-01 -Name IFRS -Number 19 -IssueDate 2025-01-01 -Paragraph B18 -Subparagraph b -URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=19&code=ifrs-tx-2025-en-r&anchor=para_B18_b&doctype=Appendix&subtype=B -URIDate 2025-03-27 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Note Expiry date 2027-01-01 -Name IAS -Number 1 -IssueDate 2025-01-01 -Paragraph 138 -Subparagraph b -URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=1&code=ifrs-tx-2025-en-b&anchor=para_138_b&doctype=Standard -URIDate 2025-03-27 + Details
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- Definition The principal place of business of a joint operation. [Refer: Total for all joint operations [member]; Principal place of business] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 12 -IssueDate 2025-01-01 -Paragraph 21 -Subparagraph a -Clause iii -URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=12&code=ifrs-tx-2025-en-r&anchor=para_21_a_iii&doctype=Standard -URIDate 2025-03-27 + Details
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