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Intangible Assets - Summary of Intangible Assets (Detail) - KRW (₩) ₩ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2024 | Dec. 31, 2023 | Dec. 31, 2022
Disclosure of detailed information about intangible assets [line items] |  |  |
Beginning, net | ₩ 2,533,861 | ₩ 3,129,833 |
Acquisition and capital expenditure | 221,245 | 309,737 |
Disposal and termination | (20,856) | (11,640) |
Amortization | (651,649) | (691,909) | ₩ (627,261)
Impairment | (239,312) | (236,207) |
Acquisition and disposition of businesses | (13,846) | 6,030 |
Others | 33,297 | 28,017 |
Ending, net | 1,862,740 | 2,533,861 | 3,129,833
Gross carrying amount [member] |  |  |
Disclosure of detailed information about intangible assets [line items] |  |  |
Beginning, net | 8,163,459 | 8,148,293 |
Ending, net | 8,296,758 | 8,163,459 | 8,148,293
Accumulated depreciation and amortisation [member] |  |  |
Disclosure of detailed information about intangible assets [line items] |  |  |
Beginning, net | (5,629,598) | (5,018,460) |
Ending, net | (6,434,018) | (5,629,598) | (5,018,460)
Goodwill [member] |  |  |
Disclosure of detailed information about intangible assets [line items] |  |  |
Beginning, net | 488,427 | 708,223 |
Acquisition and capital expenditure | 0 |  |
Disposal and termination |  | 0 |
Amortization |  | 0 |
Impairment | (211,806) | (230,352) |
Acquisition and disposition of businesses | (4,214) | 6,207 |
Others | 1,372 | 4,349 |
Ending, net | 273,779 | 488,427 | 708,223
Goodwill [member] | Gross carrying amount [member] |  |  |
Disclosure of detailed information about intangible assets [line items] |  |  |
Beginning, net | 1,036,354 | 1,037,887 |
Ending, net | 1,055,180 | 1,036,354 | 1,037,887
Goodwill [member] | Accumulated depreciation and amortisation [member] |  |  |
Disclosure of detailed information about intangible assets [line items] |  |  |
Beginning, net | (547,927) | (329,664) |
Ending, net | (781,401) | (547,927) | (329,664)
Development costs [member] |  |  |
Disclosure of detailed information about intangible assets [line items] |  |  |
Beginning, net | 138,600 | 171,856 |
Acquisition and capital expenditure | 12,417 | 33,078 |
Disposal and termination | (8,394) | (4,812) |
Amortization | (39,959) | (63,052) |
Impairment | 0 | (128) |
Acquisition and disposition of businesses | 0 |  |
Others | 1,447 | 1,658 |
Ending, net | 104,111 | 138,600 | 171,856
Development costs [member] | Gross carrying amount [member] |  |  |
Disclosure of detailed information about intangible assets [line items] |  |  |
Beginning, net | 1,790,446 | 1,803,687 |
Ending, net | 1,763,627 | 1,790,446 | 1,803,687
Development costs [member] | Accumulated depreciation and amortisation [member] |  |  |
Disclosure of detailed information about intangible assets [line items] |  |  |
Beginning, net | (1,651,846) | (1,631,831) |
Ending, net | (1,659,516) | (1,651,846) | (1,631,831)
Software [member] |  |  |
Disclosure of detailed information about intangible assets [line items] |  |  |
Beginning, net | 152,662 | 155,076 |
Acquisition and capital expenditure | 23,404 | 38,603 |
Disposal and termination | (2,206) | (397) |
Amortization | (50,811) | (52,265) |
Impairment | (118) | (16) |
Acquisition and disposition of businesses | (116) | (108) |
Others | 31,776 | 11,769 |
Ending, net | 154,591 | 152,662 | 155,076
Software [member] | Gross carrying amount [member] |  |  |
Disclosure of detailed information about intangible assets [line items] |  |  |
Beginning, net | 1,196,329 | 1,156,951 |
Ending, net | 1,251,365 | 1,196,329 | 1,156,951
Software [member] | Accumulated depreciation and amortisation [member] |  |  |
Disclosure of detailed information about intangible assets [line items] |  |  |
Beginning, net | (1,043,667) | (1,001,875) |
Ending, net | (1,096,774) | (1,043,667) | (1,001,875)
Frequency usage rights [member] |  |  |
Disclosure of detailed information about intangible assets [line items] |  |  |
Beginning, net | 1,138,192 | 1,488,256 |
Acquisition and capital expenditure |  | 37 |
Amortization | (348,297) | (350,276) |
Others | 2,646 | 175 |
Ending, net | 792,541 | 1,138,192 | 1,488,256
Frequency usage rights [member] | Gross carrying amount [member] |  |  |
Disclosure of detailed information about intangible assets [line items] |  |  |
Beginning, net | 2,415,243 | 2,617,707 |
Ending, net | 2,415,507 | 2,415,243 | 2,617,707
Frequency usage rights [member] | Accumulated depreciation and amortisation [member] |  |  |
Disclosure of detailed information about intangible assets [line items] |  |  |
Beginning, net | (1,277,051) | (1,129,451) |
Ending, net | (1,622,966) | (1,277,051) | (1,129,451)
Others [member] |  |  |
Disclosure of detailed information about intangible assets [line items] |  |  |
Beginning, net | 615,980 | 606,422 |
Acquisition and capital expenditure | 185,424 | 238,019 |
Disposal and termination | (10,256) | (6,431) |
Amortization | (212,582) | (226,316) |
Impairment | (27,388) | (5,711) |
Acquisition and disposition of businesses | (9,516) | (69) |
Others | (3,944) | 10,066 |
Ending, net | 537,718 | 615,980 | 606,422
Others [member] | Gross carrying amount [member] |  |  |
Disclosure of detailed information about intangible assets [line items] |  |  |
Beginning, net | 1,725,087 | 1,532,061 |
Ending, net | 1,811,079 | 1,725,087 | 1,532,061
Others [member] | Accumulated depreciation and amortisation [member] |  |  |
Disclosure of detailed information about intangible assets [line items] |  |  |
Beginning, net | (1,109,107) | (925,639) |
Ending, net | ₩ (1,273,361) | ₩ (1,109,107) | ₩ (925,639)

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