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Segment Information - Summary of Segment Information (Detail) - KRW (₩) ₩ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2021 | Dec. 31, 2020 | Dec. 31, 2019
Disclosure of operating segments [Line Items] |  |  |
Operating revenues | ₩ 25,205,659 | ₩ 24,440,647 | ₩ 24,899,189
Operating income (loss) | 1,699,397 | 1,022,333 | 1,026,970
Depreciation and Amortization | 3,607,637 | 3,634,284 | 3,629,492
Operating segments [member] |  |  |
Disclosure of operating segments [Line Items] |  |  |
Operating revenues | 29,599,457 | 28,612,919 | 28,863,426
Operating income (loss) | 1,743,372 | 1,175,172 | 1,080,040
Depreciation and Amortization | 3,712,506 | 3,718,122 | 3,709,297
Operating segments [member] | ICT [member] |  |  |
Disclosure of operating segments [Line Items] |  |  |
Operating revenues | 18,734,342 | 18,275,765 | 18,527,631
Operating income (loss) | 1,170,920 | 809,741 | 634,046
Depreciation and Amortization | 3,217,643 | 3,233,878 | 3,229,159
Operating segments [member] | Finance [member] |  |  |
Disclosure of operating segments [Line Items] |  |  |
Operating revenues | 3,636,260 | 3,686,430 | 3,795,185
Operating income (loss) | 137,779 | 85,008 | 158,235
Depreciation and Amortization | 48,542 | 53,098 | 27,852
Operating segments [member] | Satellite TV [member] |  |  |
Disclosure of operating segments [Line Items] |  |  |
Operating revenues | 772,950 | 706,631 | 694,637
Operating income (loss) | 76,926 | 71,345 | 69,357
Depreciation and Amortization | 91,306 | 84,931 | 94,992
Operating segments [member] | Others [member] |  |  |
Disclosure of operating segments [Line Items] |  |  |
Operating revenues | 6,455,905 | 5,944,093 | 5,845,973
Operating income (loss) | 357,747 | 209,078 | 218,402
Depreciation and Amortization | 355,015 | 346,215 | 357,294
Elimination [member] |  |  |
Disclosure of operating segments [Line Items] |  |  |
Operating revenues | (4,393,798) | (4,172,272) | (3,964,237)
Operating income (loss) | (43,975) | (152,839) | (53,070)
Depreciation and Amortization | ₩ (104,869) | ₩ (83,838) | ₩ (79,805)

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