XML 242 R232.htm IDEA: XBRL DOCUMENT v3.26.1
Commitments and Contingencies - Summary of SOC Projects (Parenthetical) (Detail) - SOC Projects [member]
₩ in Millions
Dec. 31, 2025
KRW (₩)
Funding Obligation [Member]  
Disclosure of contingent liabilities [line items]  
Estimated financial effect of contigent of liabilities ₩ 1,619,113
Funding Obligation [Member] | Pocheon Hwado Highway Corp [Member]  
Disclosure of contingent liabilities [line items]  
Estimated financial effect of contigent of liabilities 307,273
Funding Obligation [Member] | POHANG E&E Co., LTD, Pureun Tongyeong Enviro Co., Ltd, Pure Gimpo.Co.,Ltd, and Clean Iksan Co.,Ltd [member]  
Disclosure of contingent liabilities [line items]  
Estimated financial effect of contigent of liabilities 90,387
Other Shares [Member]  
Disclosure of contingent liabilities [line items]  
Estimated financial effect of contigent of liabilities 7,702,054
Other Shares [Member] | Pocheon Hwado Highway Corp [Member]  
Disclosure of contingent liabilities [line items]  
Estimated financial effect of contigent of liabilities 555,848
Other Shares [Member] | POHANG E&E Co., LTD, Pureun Tongyeong Enviro Co., Ltd, Pure Gimpo.Co.,Ltd, and Clean Iksan Co.,Ltd [member]  
Disclosure of contingent liabilities [line items]  
Estimated financial effect of contigent of liabilities 163,819
POSCO DX Co., Ltd.[member] | Jeonnong Schoo Keeper Co. And Others [Member] | Other related parties [member]  
Disclosure of contingent liabilities [line items]  
Approved Loan Amount Including Other Interests 1,122,320
Outstanding Balance Of Loan Including Other Interests ₩ 337,508