Employment Benefits - Net Defined Benefit Liability and Asset (Details) - KRW (₩) ₩ in Millions	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Disclosure of defined benefit plans [line items]
Beginning balance	₩ 1,899,782
Changes in net defined benefit liability (asset)
Current service cost	524,942	₩ 509,520	₩ 440,300
Remeasurement component	(337,298)	84,775
Past service cost	5,483	(2,027)	301,442
Ending balance	1,654,870	1,899,782
Defined benefit obligation
Disclosure of defined benefit plans [line items]
Beginning balance	4,570,614	4,035,400
Changes in net defined benefit liability (asset)
Current service cost	524,942	509,520
Interest cost	91,877	83,248
Remeasurement component	(345,755)	84,385
Past service cost	5,483	(2,027)
Actual payments	(282,794)	(139,956)
Others	50	44
Ending balance	4,564,417	4,570,614	4,035,400
Plan assets
Disclosure of defined benefit plans [line items]
Beginning balance	2,670,832	2,111,313
Changes in net defined benefit liability (asset)
Interest cost	52,782	42,742
Remeasurement component	(8,457)	(390)
Contributions by the employers	317,707	582,275
Actual payments	(123,317)	(65,108)
Ending balance	₩ 2,909,547	₩ 2,670,832	₩ 2,111,313

No definition available.

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The decrease (increase) in the net defined benefit liability (asset) resulting from contributions to a defined benefit plan by plan participants. [Refer: Net defined benefit liability (asset); Defined benefit plans [member]]

+ References

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The increase (decrease) in the net defined benefit liability (asset) resulting from employee service in the current period. [Refer: Net defined benefit liability (asset)]

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No definition available.

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The decrease (increase) in a net defined benefit liability (asset) resulting from the remeasurement of that net defined benefit liability (asset). [Refer: Net defined benefit liability (asset)]

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The increase (decrease) in the net defined benefit liability (asset) resulting from changes that the entity does not separately disclose in the same statement or note. [Refer: Net defined benefit liability (asset)]

+ References

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The increase (decrease) in the net defined benefit liability (asset) resulting from the passage of time. [Refer: Interest expense; Net defined benefit liability (asset)]

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The increase (decrease) in the net defined benefit liability (asset) resulting from past service cost. Past service cost is the change in the present value of the defined benefit obligation for employee service in prior periods, resulting from a plan amendment (the introduction or withdrawal of, or changes to, a defined benefit plan) or a curtailment (a significant reduction by the entity in the number of employees covered by a plan). [Refer: Net defined benefit liability (asset); Defined benefit plans [member]]

+ References

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The decrease (increase) in the net defined benefit liability (asset) resulting from payments from the plan. [Refer: Net defined benefit liability (asset)]

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