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Intangible Assets - Summary of Intangible Assets (Detail) - KRW (₩) ₩ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2021 | Dec. 31, 2020 | Dec. 31, 2019
Disclosure of detailed information about intangible assets [line items] |  |  |
Beginning, net | ₩ 2,161,258 | ₩ 2,834,037 |
Acquisition and capital expenditure | 1,720,619 | 165,630 |
Disposal and termination | (13,783) | (13,820) |
Amortization | (604,744) | (628,154) | ₩ (660,705)
Impairment | (3,748) | (211,637) |
Changes in scope of consolidation | 156,253 | 4,342 |
Others | 31,478 | 10,860 |
Ending, net | 3,447,333 | 2,161,258 | 2,834,037
Gross carrying amount [member] |  |  |
Disclosure of detailed information about intangible assets [line items] |  |  |
Beginning, net | 7,898,325 | 7,996,482 |
Ending, net | 7,942,556 | 7,898,325 | 7,996,482
Accumulated depreciation and amortisation [member] |  |  |
Disclosure of detailed information about intangible assets [line items] |  |  |
Beginning, net | (5,737,067) | (5,162,445) |
Ending, net | (4,495,223) | (5,737,067) | (5,162,445)
Goodwill [member] |  |  |
Disclosure of detailed information about intangible assets [line items] |  |  |
Beginning, net | 230,085 | 235,570 |
Acquisition and capital expenditure | 467,394 |  |
Changes in scope of consolidation | (607) |  |
Others | 0 | (5,485) |
Ending, net | 696,872 | 230,085 | 235,570
Goodwill [member] | Gross carrying amount [member] |  |  |
Disclosure of detailed information about intangible assets [line items] |  |  |
Beginning, net | 536,093 | 541,596 |
Ending, net | 1,002,530 | 536,093 | 541,596
Goodwill [member] | Accumulated depreciation and amortisation [member] |  |  |
Disclosure of detailed information about intangible assets [line items] |  |  |
Beginning, net | (306,008) | (306,026) |
Ending, net | (305,658) | (306,008) | (306,026)
Development costs [member] |  |  |
Disclosure of detailed information about intangible assets [line items] |  |  |
Beginning, net | 280,999 | 272,634 |
Acquisition and capital expenditure | 38,113 | 26,990 |
Disposal and termination | (7,893) | (1,849) |
Amortization | (92,230) | (104,938) |
Impairment | (216) |  |
Changes in scope of consolidation | 8,640 | 575 |
Others | 960 | 87,587 |
Ending, net | 228,373 | 280,999 | 272,634
Development costs [member] | Gross carrying amount [member] |  |  |
Disclosure of detailed information about intangible assets [line items] |  |  |
Beginning, net | 1,767,422 | 1,661,372 |
Ending, net | 1,812,377 | 1,767,422 | 1,661,372
Development costs [member] | Accumulated depreciation and amortisation [member] |  |  |
Disclosure of detailed information about intangible assets [line items] |  |  |
Beginning, net | (1,486,423) | (1,388,738) |
Ending, net | (1,584,004) | (1,486,423) | (1,388,738)
Software [member] |  |  |
Disclosure of detailed information about intangible assets [line items] |  |  |
Beginning, net | 146,000 | 137,381 |
Acquisition and capital expenditure | 36,437 | 37,077 |
Disposal and termination | (506) | (105) |
Amortization | (52,547) | (54,191) |
Impairment | (316) | (1,776) |
Changes in scope of consolidation | (4,548) | 77 |
Others | 14,905 | 27,537 |
Ending, net | 139,425 | 146,000 | 137,381
Software [member] | Gross carrying amount [member] |  |  |
Disclosure of detailed information about intangible assets [line items] |  |  |
Beginning, net | 1,053,980 | 978,139 |
Ending, net | 1,083,426 | 1,053,980 | 978,139
Software [member] | Accumulated depreciation and amortisation [member] |  |  |
Disclosure of detailed information about intangible assets [line items] |  |  |
Beginning, net | (907,980) | (840,758) |
Ending, net | (944,001) | (907,980) | (840,758)
Frequency usage rights [member] |  |  |
Disclosure of detailed information about intangible assets [line items] |  |  |
Beginning, net | 1,160,663 | 1,753,941 |
Acquisition and capital expenditure | 1,065,096 |  |
Disposal and termination | (276) | 0 |
Amortization | (386,741) | (399,348) |
Impairment | 0 | (193,194) |
Others | 389 | (736) |
Ending, net | 1,839,131 | 1,160,663 | 1,753,941
Frequency usage rights [member] | Gross carrying amount [member] |  |  |
Disclosure of detailed information about intangible assets [line items] |  |  |
Beginning, net | 3,373,095 | 3,622,327 |
Ending, net | 2,617,647 | 3,373,095 | 3,622,327
Frequency usage rights [member] | Accumulated depreciation and amortisation [member] |  |  |
Disclosure of detailed information about intangible assets [line items] |  |  |
Beginning, net | (2,212,432) | (1,868,386) |
Ending, net | (778,516) | (2,212,432) | (1,868,386)
Others [member] |  |  |
Disclosure of detailed information about intangible assets [line items] |  |  |
Beginning, net | 343,511 | 434,511 |
Acquisition and capital expenditure | 113,579 | 101,563 |
Disposal and termination | (5,108) | (11,866) |
Amortization | (73,226) | (69,677) |
Impairment | (3,216) | (16,667) |
Changes in scope of consolidation | 152,768 | 3,690 |
Others | 15,224 | (98,043) |
Ending, net | 543,532 | 343,511 | 434,511
Others [member] | Gross carrying amount [member] |  |  |
Disclosure of detailed information about intangible assets [line items] |  |  |
Beginning, net | 1,167,735 | 1,193,048 |
Ending, net | 1,426,576 | 1,167,735 | 1,193,048
Others [member] | Accumulated depreciation and amortisation [member] |  |  |
Disclosure of detailed information about intangible assets [line items] |  |  |
Beginning, net | (824,224) | (758,537) |
Ending, net | ₩ (883,044) | ₩ (824,224) | ₩ (758,537)

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