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Financial Risk Management - Summary of Cash Outflow and Inflow of Derivatives Settled Gross or Net are Undiscounted Contractual Cash Flow (Detail) - KRW (₩) ₩ in Millions | Dec. 31, 2021 | Dec. 31, 2020 | Dec. 31, 2019
--- | --- | --- | ---
Derivatives held for trading |  |  |
Outflows | ₩ 158,284 |  |
Derivatives settled gross |  |  |
Outflow | 3,078,733 | ₩ 2,925,965 | ₩ 2,760,957
Inflow | 3,167,878 | 2,804,618 | 2,857,949
Less than 1 year [member] |  |  |
Derivatives held for trading |  |  |
Outflows | 0 |  |
Derivatives settled gross |  |  |
Outflow | 843,489 | 248,300 | 650,497
Inflow | 856,508 | 249,301 | 684,720
1-5 years [member] |  |  |
Derivatives held for trading |  |  |
Outflows | 158,284 |  |
Derivatives settled gross |  |  |
Outflow | 1,857,942 | 2,179,046 | 1,602,513
Inflow | 1,917,236 | 2,074,747 | 1,648,746
More than 5 years [member] |  |  |
Derivatives held for trading |  |  |
Outflows | 0 |  |
Derivatives settled gross |  |  |
Outflow | 377,302 | 498,619 | 507,947
Inflow | ₩ 394,134 | ₩ 480,570 | ₩ 524,483

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