XML 184 R132.htm IDEA: XBRL DOCUMENT
v3.20.1

Borrowings - Summary of Borrowings (Detail) ¥ in Thousands, $ in Thousands, ₩ in Millions | 12 Months Ended |  |
--- | --- | --- | ---
Dec. 31, 2019 KRW (₩) | Dec. 31, 2019 USD ($) | Dec. 31, 2019 JPY (¥) | Dec. 31, 2018 KRW (₩) | Dec. 31, 2018 USD ($) | Dec. 31, 2018 JPY (¥)
Disclosure of detailed information about borrowings [line items] |  |  |  |  |  |
Less: Current portion | ₩ (1,185,725) |  |  | ₩ (1,368,481) |  |
Borrowings | ₩ 7,298,867 |  |  | 6,648,293 |  |
Nov 01, 2024 [memebr] |  |  |  |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |  |  |  |
Maturity | Nov 01, 2024 |  |  |  |  |
Annual interest rates adjustment rate | 0.98% | 0.98% | 0.98% |  |  |
July 19, 2022 [member] |  |  |  |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |  |  |  |
Maturity | July 19, 2022 |  |  |  |  |
July 19, 2024 [memeber] |  |  |  |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |  |  |  |
Maturity | July 19, 2024 |  |  |  |  |
Gross carrying amount [member] |  |  |  |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |  |  |  |
Borrowings | ₩ 7,319,647 |  |  |  |  |
Gross carrying amount [member] | Sept. 07, 2034 [member] |  |  |  |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |  |  |  |
Maturity | Sept. 07, 2034 |  |  |  |  |
Annual interest rates | 6.50% | 6.50% | 6.50% |  |  |
Gross carrying amount [member] | Apr. 22, 2019 [member] |  |  |  |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |  |  |  |
Maturity | Apr. 22, 2019 |  |  |  |  |
Gross carrying amount [member] | July 18, 2026 [member] |  |  |  |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |  |  |  |
Maturity | July 18, 2026 |  |  |  |  |
Annual interest rates | 2.50% | 2.50% | 2.50% |  |  |
Gross carrying amount [member] | Aug 07, 2022 [member] |  |  |  |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |  |  |  |
Maturity | Aug 07, 2022 |  |  |  |  |
Annual interest rates | 2.63% | 2.63% | 2.63% |  |  |
Gross carrying amount [member] | Aug 23, 2020 [member] |  |  |  |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |  |  |  |
Maturity | Aug 23, 2020 |  |  |  |  |
Annual interest rates description | LIBOR(3M)+0.40% |  |  |  |  |
Annual interest rates adjustment rate | 0.40% | 0.40% | 0.40% |  |  |
Gross carrying amount [member] | Aug 23, 2023 [member] |  |  |  |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |  |  |  |
Maturity | Aug 23, 2023 |  |  |  |  |
Annual interest rates description | LIBOR(3M)+0.90% |  |  |  |  |
Annual interest rates adjustment rate | 0.90% | 0.90% | 0.90% |  |  |
Gross carrying amount [member] | Nov 01, 2024 [memebr] |  |  |  |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |  |  |  |
Annual interest rates description | LIBOR(3M)+0.98% |  |  |  |  |
Gross carrying amount [member] | July 06, 2020 [member] |  |  |  |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |  |  |  |
Maturity | July 06, 2020 |  |  |  |  |
Annual interest rates | 0.31% | 0.31% | 0.31% |  |  |
Gross carrying amount [member] | July 06, 2021 [member] |  |  |  |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |  |  |  |
Maturity | July 06, 2021 |  |  |  |  |
Annual interest rates | 0.38% | 0.38% | 0.38% |  |  |
Gross carrying amount [member] | Nov 13, 2020 [member] |  |  |  |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |  |  |  |
Maturity | Nov 13, 2020 |  |  |  |  |
Annual interest rates | 0.30% | 0.30% | 0.30% |  |  |
Gross carrying amount [member] | July 19, 2022 [member] |  |  |  |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |  |  |  |
Annual interest rates | 0.22% | 0.22% | 0.22% |  |  |
Gross carrying amount [member] | July 19, 2024 [memeber] |  |  |  |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |  |  |  |
Annual interest rates | 0.33% | 0.33% | 0.33% |  |  |
Gross carrying amount [member] | Apr. 26, 2021 [member] |  |  |  |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |  |  |  |
Maturity | Apr. 26, 2021 |  |  |  |  |
Annual interest rates | 4.71% | 4.71% | 4.71% |  |  |
Gross carrying amount [member] | Aug. 26, 2021 [member] |  |  |  |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |  |  |  |
Maturity | Aug. 26, 2021 |  |  |  |  |
Annual interest rates | 4.09% | 4.09% | 4.09% |  |  |
Gross carrying amount [member] | Oct. 28, 2021 [member] |  |  |  |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |  |  |  |
Maturity | Oct. 28, 2021 |  |  |  |  |
Annual interest rates | 4.31% | 4.31% | 4.31% |  |  |
Gross carrying amount [member] | Dec. 22, 2021 [member] |  |  |  |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |  |  |  |
Maturity | Dec. 22, 2021 |  |  |  |  |
Annual interest rates | 4.09% | 4.09% | 4.09% |  |  |
Gross carrying amount [member] | Dec. 22, 2031 [member] |  |  |  |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |  |  |  |
Maturity | Dec. 22, 2031 |  |  |  |  |
Annual interest rates | 4.27% | 4.27% | 4.27% |  |  |
Gross carrying amount [member] | Apr. 10, 2023 [member] |  |  |  |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |  |  |  |
Maturity | Apr. 10, 2023 |  |  |  |  |
Annual interest rates | 2.95% | 2.95% | 2.95% |  |  |
Gross carrying amount [member] | Apr. 10, 2033 [member] |  |  |  |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |  |  |  |
Maturity | Apr. 10, 2033 |  |  |  |  |
Annual interest rates | 3.17% | 3.17% | 3.17% |  |  |
Gross carrying amount [member] | Sept. 16, 2020 [member] |  |  |  |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |  |  |  |
Maturity | Sept. 16, 2020 |  |  |  |  |
Annual interest rates | 3.65% | 3.65% | 3.65% |  |  |
Gross carrying amount [member] | June 26, 2019 [member] |  |  |  |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |  |  |  |
Maturity | June 26, 2019 |  |  |  |  |
Gross carrying amount [member] | June 26, 2024 [member] |  |  |  |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |  |  |  |
Maturity | June 26, 2024 |  |  |  |  |
Annual interest rates | 3.42% | 3.42% | 3.42% |  |  |
Gross carrying amount [member] | June 26, 2034 [member] |  |  |  |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |  |  |  |
Maturity | June 26, 2034 |  |  |  |  |
Annual interest rates | 3.70% | 3.70% | 3.70% |  |  |
Gross carrying amount [member] | Sept. 02, 2019 [member] |  |  |  |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |  |  |  |
Maturity | Sept. 02, 2019 |  |  |  |  |
Gross carrying amount [member] | Sept. 02, 2024 [member] |  |  |  |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |  |  |  |
Maturity | Sept. 02, 2024 |  |  |  |  |
Annual interest rates | 3.31% | 3.31% | 3.31% |  |  |
Gross carrying amount [member] | Sept. 02, 2034 [member] |  |  |  |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |  |  |  |
Maturity | Sept. 02, 2034 |  |  |  |  |
Annual interest rates | 3.55% | 3.55% | 3.55% |  |  |
Gross carrying amount [member] | Jan. 29, 2020 [member] |  |  |  |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |  |  |  |
Maturity | Jan. 29, 2020 |  |  |  |  |
Annual interest rates | 2.26% | 2.26% | 2.26% |  |  |
Gross carrying amount [member] | Jan. 29, 2025 [member] |  |  |  |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |  |  |  |
Maturity | Jan. 29, 2025 |  |  |  |  |
Annual interest rates | 2.45% | 2.45% | 2.45% |  |  |
Gross carrying amount [member] | Jan. 29, 2035 [member] |  |  |  |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |  |  |  |
Maturity | Jan. 29, 2035 |  |  |  |  |
Annual interest rates | 2.71% | 2.71% | 2.71% |  |  |
Gross carrying amount [member] | Jan. 28, 2019 [member] |  |  |  |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |  |  |  |
Maturity | Jan. 28, 2019 |  |  |  |  |
Gross carrying amount [member] | Jan. 28, 2021 [member] |  |  |  |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |  |  |  |
Maturity | Jan. 28, 2021 |  |  |  |  |
Annual interest rates | 1.95% | 1.95% | 1.95% |  |  |
Gross carrying amount [member] | Jan. 28, 2026 [member] |  |  |  |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |  |  |  |
Maturity | Jan. 28, 2026 |  |  |  |  |
Annual interest rates | 2.20% | 2.20% | 2.20% |  |  |
Gross carrying amount [member] | Jan. 28, 2036 [member] |  |  |  |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |  |  |  |
Maturity | Jan. 28, 2036 |  |  |  |  |
Annual interest rates | 2.35% | 2.35% | 2.35% |  |  |
Borrowings | ₩ 70,000 |  |  | 70,000 |  |
Gross carrying amount [member] | Jan. 29, 2021 [member] |  |  |  |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |  |  |  |
Maturity | Jan. 29, 2021 |  |  |  |  |
Annual interest rates | 2.55% | 2.55% | 2.55% |  |  |
Borrowings | ₩ 110,000 |  |  | 110,000 |  |
Gross carrying amount [member] | Jan. 30, 2023 [member] |  |  |  |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |  |  |  |
Maturity | Jan. 30, 2023 |  |  |  |  |
Annual interest rates | 2.75% | 2.75% | 2.75% |  |  |
Borrowings | ₩ 150,000 |  |  | 150,000 |  |
Gross carrying amount [member] | Jan. 30, 2028 [member] |  |  |  |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |  |  |  |
Maturity | Jan. 30, 2028 |  |  |  |  |
Annual interest rates | 2.95% | 2.95% | 2.95% |  |  |
Borrowings | ₩ 170,000 |  |  | 170,000 |  |
Gross carrying amount [member] | Jan. 30, 2038 [member] |  |  |  |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |  |  |  |
Maturity | Jan. 30, 2038 |  |  |  |  |
Annual interest rates | 2.93% | 2.93% | 2.93% |  |  |
Borrowings | ₩ 70,000 |  |  | 70,000 |  |
Gross carrying amount [member] | Jan, 14, 2022 [member] |  |  |  |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |  |  |  |
Maturity | Jan, 14, 2022 |  |  |  |  |
Annual interest rates | 2.05% | 2.05% | 2.05% |  |  |
Gross carrying amount [member] | Jan, 15, 2024 [member] |  |  |  |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |  |  |  |
Maturity | Jan, 15, 2024 |  |  |  |  |
Annual interest rates | 2.09% | 2.09% | 2.09% |  |  |
Gross carrying amount [member] | Jan, 15, 2029 [member] |  |  |  |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |  |  |  |
Maturity | Jan, 15, 2029 |  |  |  |  |
Annual interest rates | 2.16% | 2.16% | 2.16% |  |  |
Gross carrying amount [member] | Jan, 14, 2039 [member] |  |  |  |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |  |  |  |
Maturity | Jan, 14, 2039 |  |  |  |  |
Annual interest rates | 2.21% | 2.21% | 2.21% |  |  |
Gross carrying amount [member] | Oct, 11, 2022 [member] |  |  |  |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |  |  |  |
Maturity | Oct, 11, 2022 |  |  |  |  |
Annual interest rates | 1.55% | 1.55% | 1.55% |  |  |
Gross carrying amount [member] | Oct, 11, 2024 [member] |  |  |  |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |  |  |  |
Maturity | Oct, 11, 2024 |  |  |  |  |
Annual interest rates | 1.58% | 1.58% | 1.58% |  |  |
Gross carrying amount [member] | Oct, 11, 2029 [member] |  |  |  |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |  |  |  |
Maturity | Oct, 11, 2029 |  |  |  |  |
Annual interest rates | 1.62% | 1.62% | 1.62% |  |  |
Gross carrying amount [member] | Oct, 11, 2039 [member] |  |  |  |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |  |  |  |
Maturity | Oct, 11, 2039 |  |  |  |  |
Annual interest rates | 1.67% | 1.67% | 1.67% |  |  |
Debentures [member] |  |  |  |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |  |  |  |
Less: Current portion | ₩ (1,052,032) |  |  | (880,940) |  |
Discount on bonds | (20,780) |  |  | (20,056) |  |
Borrowings | 5,972,554 |  |  | 5,128,649 |  |
Debentures [member] | Gross carrying amount [member] |  |  |  |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |  |  |  |
Borrowings | 7,045,366 |  |  | 6,029,645 |  |
Debentures [member] | Gross carrying amount [member] | Sept. 07, 2034 [member] |  |  |  |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |  |  |  |
Borrowings | 115,780 | $ 100,000 |  | 111,810 | $ 100,000 |
Debentures [member] | Gross carrying amount [member] | Apr. 22, 2019 [member] |  |  |  |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |  |  |  |
Borrowings |  |  |  | 391,335 | 350,000 |
Debentures [member] | Gross carrying amount [member] | July 18, 2026 [member] |  |  |  |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |  |  |  |
Borrowings | 463,120 | 400,000 |  | 447,240 | 400,000 |
Debentures [member] | Gross carrying amount [member] | Aug 07, 2022 [member] |  |  |  |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |  |  |  |
Borrowings | 463,120 | 400,000 |  | 447,240 | 400,000 |
Debentures [member] | Gross carrying amount [member] | Aug 23, 2020 [member] |  |  |  |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |  |  |  |
Borrowings | 231,560 | 200,000 |  | 223,620 | 200,000 |
Debentures [member] | Gross carrying amount [member] | Aug 23, 2023 [member] |  |  |  |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |  |  |  |
Borrowings | 115,780 | 100,000 |  | 111,810 | $ 100,000 |
Debentures [member] | Gross carrying amount [member] | Nov 01, 2024 [memebr] |  |  |  |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |  |  |  |
Borrowings | 405,230 | $ 350,000 |  |  |  |
Debentures [member] | Gross carrying amount [member] | July 06, 2020 [member] |  |  |  |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |  |  |  |
Borrowings | 42,539 |  | ¥ 4,000,000 | 40,527 |  | ¥ 4,000,000
Debentures [member] | Gross carrying amount [member] | July 06, 2021 [member] |  |  |  |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |  |  |  |
Borrowings | 170,155 |  | 16,000,000 | 162,109 |  | 16,000,000
Debentures [member] | Gross carrying amount [member] | Nov 13, 2020 [member] |  |  |  |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |  |  |  |
Borrowings | 319,041 |  | 30,000,000 | 303,954 |  | ¥ 30,000,000
Debentures [member] | Gross carrying amount [member] | July 19, 2022 [member] |  |  |  |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |  |  |  |
Borrowings | 314,787 |  | 29,600,000 |  |  |
Debentures [member] | Gross carrying amount [member] | July 19, 2024 [memeber] |  |  |  |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |  |  |  |
Borrowings | 4,254 |  | ¥ 400,000 |  |  |
Debentures [member] | Gross carrying amount [member] | Apr. 26, 2021 [member] |  |  |  |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |  |  |  |
Borrowings | 380,000 |  |  | 380,000 |  |
Debentures [member] | Gross carrying amount [member] | Aug. 26, 2021 [member] |  |  |  |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |  |  |  |
Borrowings | 250,000 |  |  | 250,000 |  |
Debentures [member] | Gross carrying amount [member] | Oct. 28, 2021 [member] |  |  |  |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |  |  |  |
Borrowings | 100,000 |  |  | 100,000 |  |
Debentures [member] | Gross carrying amount [member] | Dec. 22, 2021 [member] |  |  |  |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |  |  |  |
Borrowings | 90,000 |  |  | 90,000 |  |
Debentures [member] | Gross carrying amount [member] | Dec. 22, 2031 [member] |  |  |  |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |  |  |  |
Borrowings | 160,000 |  |  | 160,000 |  |
Debentures [member] | Gross carrying amount [member] | Apr. 10, 2018 [member] |  |  |  |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |  |  |  |
Borrowings | 190,000 |  |  | 190,000 |  |
Debentures [member] | Gross carrying amount [member] | Apr. 10, 2023 [member] |  |  |  |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |  |  |  |
Borrowings | 100,000 |  |  | 100,000 |  |
Debentures [member] | Gross carrying amount [member] | Sept. 16, 2018 [member] |  |  |  |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |  |  |  |
Borrowings | 300,000 |  |  | 300,000 |  |
Debentures [member] | Gross carrying amount [member] | June 26, 2019 [member] |  |  |  |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |  |  |  |
Borrowings |  |  |  | 170,000 |  |
Debentures [member] | Gross carrying amount [member] | June 26, 2024 [member] |  |  |  |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |  |  |  |
Borrowings | 110,000 |  |  | 110,000 |  |
Debentures [member] | Gross carrying amount [member] | June 26, 2034 [member] |  |  |  |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |  |  |  |
Borrowings | 100,000 |  |  | 100,000 |  |
Debentures [member] | Gross carrying amount [member] | Sept. 02, 2019 [member] |  |  |  |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |  |  |  |
Borrowings |  |  |  | 220,000 |  |
Debentures [member] | Gross carrying amount [member] | Sept. 02, 2024 [member] |  |  |  |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |  |  |  |
Borrowings | 170,000 |  |  | 170,000 |  |
Debentures [member] | Gross carrying amount [member] | Sept. 02, 2034 [member] |  |  |  |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |  |  |  |
Borrowings | 100,000 |  |  | 100,000 |  |
Debentures [member] | Gross carrying amount [member] | Jan. 29, 2020 [member] |  |  |  |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |  |  |  |
Borrowings | 160,000 |  |  | 160,000 |  |
Debentures [member] | Gross carrying amount [member] | Jan. 29, 2025 [member] |  |  |  |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |  |  |  |
Borrowings | 240,000 |  |  | 240,000 |  |
Debentures [member] | Gross carrying amount [member] | Jan. 29, 2035 [member] |  |  |  |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |  |  |  |
Borrowings | 50,000 |  |  | 50,000 |  |
Debentures [member] | Gross carrying amount [member] | Jan. 28, 2019 [member] |  |  |  |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |  |  |  |
Borrowings |  |  |  | 100,000 |  |
Debentures [member] | Gross carrying amount [member] | Jan. 28, 2021 [member] |  |  |  |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |  |  |  |
Borrowings | 130,000 |  |  | 130,000 |  |
Debentures [member] | Gross carrying amount [member] | Jan. 28, 2026 [member] |  |  |  |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |  |  |  |
Borrowings | 100,000 |  |  | ₩ 100,000 |  |
Debentures [member] | Gross carrying amount [member] | Jan, 14, 2022 [member] |  |  |  |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |  |  |  |
Borrowings | 220,000 |  |  |  |  |
Debentures [member] | Gross carrying amount [member] | Jan, 15, 2024 [member] |  |  |  |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |  |  |  |
Borrowings | 80,000 |  |  |  |  |
Debentures [member] | Gross carrying amount [member] | Jan, 15, 2029 [member] |  |  |  |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |  |  |  |
Borrowings | 110,000 |  |  |  |  |
Debentures [member] | Gross carrying amount [member] | Jan, 14, 2039 [member] |  |  |  |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |  |  |  |
Borrowings | 90,000 |  |  |  |  |
Debentures [member] | Gross carrying amount [member] | Oct, 11, 2022 [member] |  |  |  |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |  |  |  |
Borrowings | 340,000 |  |  |  |  |
Debentures [member] | Gross carrying amount [member] | Oct, 11, 2024 [member] |  |  |  |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |  |  |  |
Borrowings | 100,000 |  |  |  |  |
Debentures [member] | Gross carrying amount [member] | Oct, 11, 2029 [member] |  |  |  |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |  |  |  |
Borrowings | 50,000 |  |  |  |  |
Debentures [member] | Gross carrying amount [member] | Oct, 11, 2039 [member] |  |  |  |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |  |  |  |
Borrowings | ₩ 110,000 |  |  |  |  |

X
- Definition The amount of outstanding funds that the entity is obligated to repay. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Name IAS -Number 1 -IssueDate 2019-01-01 -Paragraph 55 -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=1&code=ifrs-tx-2019-en-r&anchor=para_55&doctype=Standard -URIDate 2019-03-27 + Details
Name: | ifrs-full_Borrowings
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition The adjustment to the basis (reference rate) used for calculation of the interest rate on borrowings. [Refer: Borrowings] + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Name IFRS -Number 7 -IssueDate 2019-01-01 -Paragraph 7 -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=7&code=ifrs-tx-2019-en-r&anchor=para_7&doctype=Standard -URIDate 2019-03-27 + Details
Name: | ifrs-full_BorrowingsAdjustmentToInterestRateBasis
Namespace Prefix: | ifrs-full_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | instant

X
- Definition The interest rate on borrowings. [Refer: Borrowings] + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Name IFRS -Number 7 -IssueDate 2019-01-01 -Paragraph 7 -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=7&code=ifrs-tx-2019-en-r&anchor=para_7&doctype=Standard -URIDate 2019-03-27 + Details
Name: | ifrs-full_BorrowingsInterestRate
Namespace Prefix: | ifrs-full_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | instant

X
- Definition The basis (reference rate) used for calculation of the interest rate on borrowings. [Refer: Borrowings] + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Name IFRS -Number 7 -IssueDate 2019-01-01 -Paragraph 7 -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=7&code=ifrs-tx-2019-en-r&anchor=para_7&doctype=Standard -URIDate 2019-03-27 + Details
Name: | ifrs-full_BorrowingsInterestRateBasis
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition The maturity of borrowings. [Refer: Borrowings] + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Name IFRS -Number 7 -IssueDate 2019-01-01 -Paragraph 7 -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=7&code=ifrs-tx-2019-en-r&anchor=para_7&doctype=Standard -URIDate 2019-03-27 + Details
Name: | ifrs-full_BorrowingsMaturity
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition The amount of current borrowings and current portion of non-current borrowings. [Refer: Borrowings] + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Name IAS -Number 1 -IssueDate 2019-01-01 -Paragraph 55 -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=1&code=ifrs-tx-2019-en-r&anchor=para_55&doctype=Standard -URIDate 2019-03-27 + Details
Name: | ifrs-full_CurrentBorrowingsAndCurrentPortionOfNoncurrentBorrowings
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Line items represent concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes of the table. + References No definition available. + Details
Name: | ifrs-full_DisclosureOfDetailedInformationAboutBorrowingsLineItems
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Discount on bonds. + References No definition available. + Details
Name: | kt_DiscountOnBonds
Namespace Prefix: | kt_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Details
Name: | ifrs-full_MaturityAxis=kt_MtnpNotesNovemberZeroOneTwentyTwentyFourMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_MaturityAxis=kt_MtnpNotesJulyOneNineTwentyTwentyTwoMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_MaturityAxis=kt_MtnpNotesJulyOneNineTwentyTwentyFourMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_CarryingAmountAccumulatedDepreciationAmortisationAndImpairmentAndGrossCarryingAmountAxis=ifrs-full_GrossCarryingAmountMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_MaturityAxis=kt_MtnpNotesSeptemberZeroSevenTwentyThirtyFourMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_MaturityAxis=kt_MtnpNotesAprilTwentyTwoTwentyNineteenMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_MaturityAxis=kt_MtnpNotesJulyEighteenTwentyTwentySixMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_MaturityAxis=kt_MtnpNotesAugustSevenTwentyTwentyTwoMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_MaturityAxis=kt_FrNotesAugustTwentyThreeTwentyTwentyMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_MaturityAxis=kt_FrNotesAugustTwentyThreeTwentyTwentyThreeMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_MaturityAxis=kt_MtnpNotesJulySixTwentyTwentyMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_MaturityAxis=kt_MtnpNotesJulySixTwentyTwentyOneMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_MaturityAxis=kt_MtnpNotesNovemberThirteenTwentyTwentyMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_MaturityAxis=kt_The1802ndPublicBondAprilTwentySixTwentyTwentyOneMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_MaturityAxis=kt_The1813rdPublicBondAugustTwentySixTwentyTwentyOneMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_MaturityAxis=kt_The1822ndPublicBondOctoberTwentyEightTwentyTwentyOneMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_MaturityAxis=kt_The1832ndPublicBondDecemberTwentyTwoTwentyTwentyOneMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_MaturityAxis=kt_The1833rdPublicBondDecemberTwentyTwoTwentyThirtyOneMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_MaturityAxis=kt_The1842ndPublicBondAprilTenTwentyTwentyThreeMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_MaturityAxis=kt_The1843rdPublicBondAprilTenTwentyThirtyThreeMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_MaturityAxis=kt_The1852ndPublicBondSeptemberSixteenTwentyTwentyMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_MaturityAxis=kt_The1862ndPublicBondJuneTwentySixTwentyNineteenMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_MaturityAxis=kt_The1863rdPublicBondJuneTwentySixTwentyTwentyFourMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_MaturityAxis=kt_The1864thPublicBondJuneTwentySixTwentyThirtyFourMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_MaturityAxis=kt_The1872ndPublicBondSeptemberZeroTwoTwentyNineteenMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_MaturityAxis=kt_The1873rdPublicBondSeptemberZeroTwoTwentyTwentyFourMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_MaturityAxis=kt_The1874thPublicBondSeptemberZeroTwoTwentyThirtyFourMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_MaturityAxis=kt_The1881stPublicBondJanuaryTwentyNineTwentyTwentyMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_MaturityAxis=kt_The1882ndPublicBondJanuaryTwentyNineTwentyTwentyFiveMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_MaturityAxis=kt_The1883rdPublicBondJanuaryTwentyNineTwentyThirtyFiveMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_MaturityAxis=kt_The1891stPublicBondJanuaryTwentyEightTwentyNineteenMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_MaturityAxis=kt_The1892ndPublicBondJanuaryTwentyEightTwentyTwentyOneMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_MaturityAxis=kt_The1893rdPublicBondJanuaryTwentyEightTwentyTwentySixMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_MaturityAxis=kt_The1894thPublicBondJanuaryTwentyEightTwentyThirtySixMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_MaturityAxis=kt_The1901stPublicBondJanuaryTwentyNineTwentyTwentyOneMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_MaturityAxis=kt_The1902ndPublicBondJanuaryThirtyTwentyTwentyThreeMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_MaturityAxis=kt_The1903rdPublicBondJanuaryThirtyTwentyTwentyEightMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_MaturityAxis=kt_The1904thPublicBondJanuaryThirtyTwentyThirtyEightMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_MaturityAxis=kt_The1911stPublicBondJanuaryFourteenTwentyTwentyTwoMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_MaturityAxis=kt_The1912ndPublicBondJanuaryFifteenTwentyTwentyFourMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_MaturityAxis=kt_The1913rdPublicBondJanuaryFifteenTwentyTwentyNineMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_MaturityAxis=kt_The1914thPublicBondJanuaryFourteenTwentyThirtyNineMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_MaturityAxis=kt_The1921stPublicBondOctoberElevenTwentyTwentyTwoMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_MaturityAxis=kt_The1922ndPublicBondOctoberElevenTwentyTwentyFourMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_MaturityAxis=kt_The1923rdPublicBondOctoberElevenTwentyTwentyNineMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_MaturityAxis=kt_The1924thPublicBondOctoberElevenTwentyThirtyNineMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_BorrowingsByNameAxis=kt_DebenturesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_MaturityAxis=kt_The1841stPublicBondAprilTenTwentyEighteenMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_MaturityAxis=kt_The1851stPublicBondSeptemberSixteenTwentyEighteenMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |