v3.26.1
Financial Risk Management - Summary of Changes in Loss Allowance for Debt Investments (Detail) - KRW (₩)
₩ in Millions
 12 Months Ended
Dec. 31, 2025
Dec. 31, 2024
Disclosure of reconciliation of changes in loss allowance and explanation of changes in gross carrying amount for financial instruments [line items]    
Beginning balance ₩ 7,488,373  
Reclassified as assets held for sale [1]   ₩ (2,516)
Ending balance 7,975,070 7,488,373
Debt Investments [member]    
Disclosure of reconciliation of changes in loss allowance and explanation of changes in gross carrying amount for financial instruments [line items]    
Beginning balance 67,585  
Remeasurement of loss allowance, net 3,282  
Transfer to lifetime ECL – not credit impaired 0  
Transfer to lifetime ECL – credit impaired 0  
Amounts written off (30,685)  
Recovery of amounts written off 633  
Reclassified as assets held for sale (502)  
Ending balance 40,313 67,585
Debt Investments [member] | 12-month expected credit losses [member]    
Disclosure of reconciliation of changes in loss allowance and explanation of changes in gross carrying amount for financial instruments [line items]    
Beginning balance 3,343  
Remeasurement of loss allowance, net 2,249  
Transfer to lifetime ECL – not credit impaired (3,330)  
Transfer to lifetime ECL – credit impaired 0  
Amounts written off 0  
Recovery of amounts written off 0  
Reclassified as assets held for sale 0  
Ending balance 2,262 3,343
Debt Investments [member] | Financial instruments not credit-impaired [member] | Lifetime expected credit losses [member]    
Disclosure of reconciliation of changes in loss allowance and explanation of changes in gross carrying amount for financial instruments [line items]    
Beginning balance 4,004  
Remeasurement of loss allowance, net 227  
Transfer to lifetime ECL – not credit impaired 3,330  
Transfer to lifetime ECL – credit impaired (4,231)  
Amounts written off 0  
Recovery of amounts written off 0  
Reclassified as assets held for sale 0  
Ending balance 3,330 4,004
Debt Investments [member] | Financial instruments credit-impaired [member] | Lifetime expected credit losses [member]    
Disclosure of reconciliation of changes in loss allowance and explanation of changes in gross carrying amount for financial instruments [line items]    
Beginning balance 60,238  
Remeasurement of loss allowance, net 806  
Transfer to lifetime ECL – not credit impaired 0  
Transfer to lifetime ECL – credit impaired 4,231  
Amounts written off (30,685)  
Recovery of amounts written off 633  
Reclassified as assets held for sale (502)  
Ending balance ₩ 34,721 ₩ 60,238
[1] The Group decided to dispose of the shares of NATE Communications Corporation (formerly, SK Communications Co., Ltd.) and SK m&service Co., Ltd., the consolidated subsidiaries, and reclassified the goodwill amounting to ₩2,516 million of SK m&service Co., Ltd. as assets held for sale.