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Borrowings - Summary of Borrowings (Detail) ¥ in Thousands, $ in Thousands, ₩ in Millions | 12 Months Ended |  |  |
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Dec. 31, 2018 KRW (₩) | Dec. 31, 2018 JPY (¥) | Dec. 31, 2018 USD ($) | Dec. 31, 2017 KRW (₩) | Dec. 31, 2017 JPY (¥) | Dec. 31, 2017 USD ($) | Jan. 01, 2017 KRW (₩)
Disclosure of detailed information about borrowings [line items] |  |  |  |  |  |  |
Less: Current portion | ₩ (1,368,481) |  |  | ₩ (1,573,474) |  |  | ₩ (1,820,001)
Borrowings | 6,648,293 |  |  | 6,683,662 |  |  |
Gross carrying amount [member] |  |  |  |  |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |  |  |  |  |
Borrowings | ₩ 6,668,349 |  |  |  |  |  |
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] | Aug. 28, 2018 [member] |  |  |  |  |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |  |  |  |  |
Maturity | Aug. 28, 2018 |  |  |  |  |  |
Gross carrying amount [member] | Apr. 22, 2019 [member] |  |  |  |  |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |  |  |  |  |
Maturity | Apr. 22, 2019 |  |  |  |  |  |
Annual interest rates | 2.63% | 2.63% | 2.63% |  |  |  |
Gross carrying amount [member] | Jan. 29, 2018 [member] |  |  |  |  |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |  |  |  |  |
Maturity | Jan. 29, 2018 |  |  |  |  |  |
Gross carrying amount [member] | Feb. 23, 2018 [member] |  |  |  |  |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |  |  |  |  |
Maturity | Feb. 23, 2018 |  |  |  |  |  |
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] | 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] | Aug. 06, 2018 [member] |  |  |  |  |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |  |  |  |  |
Maturity | Aug. 06, 2018 |  |  |  |  |  |
Gross carrying amount [member] | Mar. 29, 2018 [member] |  |  |  |  |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |  |  |  |  |
Maturity | Mar. 29, 2018 |  |  |  |  |  |
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, 2016 [member] |  |  |  |  |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |  |  |  |  |
Maturity | Aug. 26, 2018 |  |  |  |  |  |
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, 2018 [member] |  |  |  |  |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |  |  |  |  |
Maturity | Apr. 10, 2018 |  |  |  |  |  |
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, 2018 [member] |  |  |  |  |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |  |  |  |  |
Maturity | Sept. 16, 2018 |  |  |  |  |  |
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 |  |  |  |  |  |
Annual interest rates | 3.08% | 3.08% | 3.08% |  |  |  |
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 |  |  |  |  |  |
Annual interest rates | 2.97% | 2.97% | 2.97% |  |  |  |
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 |  |  |  |  |  |
Annual interest rates | 1.76% | 1.76% | 1.76% |  |  |  |
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% |  |  |  |
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% |  |  |  |
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% |  |  |  |
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% |  |  |  |
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% |  |  |  |
Gross carrying amount [member] | Apr. 22, 2018 [member] |  |  |  |  |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |  |  |  |  |
Maturity | Apr. 22, 2018 |  |  |  |  |  |
Debentures [member] |  |  |  |  |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |  |  |  |  |
Less: Current portion | ₩ (880,940) |  |  | (1,357,776) |  |  |
Discount on bonds | (20,056) |  |  | (19,347) |  |  |
Borrowings | 5,128,649 |  |  | 4,610,453 |  |  |
Debentures [member] | Gross carrying amount [member] |  |  |  |  |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |  |  |  |  |
Borrowings | 6,029,645 |  |  | 5,987,576 |  |  |
Debentures [member] | Gross carrying amount [member] | Sept. 07, 2034 [member] |  |  |  |  |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |  |  |  |  |
Borrowings | 111,810 |  | $ 100,000 | 107,140 |  | $ 100,000 |
Debentures [member] | Gross carrying amount [member] | Aug. 28, 2018 [member] |  |  |  |  |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |  |  |  |  |
Borrowings |  |  |  | 321,420 |  | 300,000 |
Debentures [member] | Gross carrying amount [member] | Apr. 22, 2019 [member] |  |  |  |  |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |  |  |  |  |
Borrowings | 391,335 |  | 350,000 | 374,990 |  | 350,000 |
Debentures [member] | Gross carrying amount [member] | Jan. 29, 2018 [member] |  |  |  |  |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |  |  |  |  |
Borrowings |  |  |  | 64,539 | ¥ 6,800,000 |  |
Debentures [member] | Gross carrying amount [member] | Feb. 23, 2018 [member] |  |  |  |  |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |  |  |  |  |
Borrowings |  |  |  | 142,367 | ¥ 15,000,000 |  |
Debentures [member] | Gross carrying amount [member] | July 18, 2026 [member] |  |  |  |  |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |  |  |  |  |
Borrowings | 447,240 |  | 400,000 | 428,560 |  | 400,000 |
Debentures [member] | Gross carrying amount [member] | Aug 07, 2022 [member] |  |  |  |  |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |  |  |  |  |
Borrowings | 447,240 |  | 400,000 | 428,560 |  | $ 400,000 |
Debentures [member] | Gross carrying amount [member] | Aug 23, 2020 [member] |  |  |  |  |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |  |  |  |  |
Borrowings | 223,620 |  | 200,000 |  |  |  |
Debentures [member] | Gross carrying amount [member] | Aug 23, 2023 [member] |  |  |  |  |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |  |  |  |  |
Borrowings | 111,810 |  | $ 100,000 |  |  |  |
Debentures [member] | Gross carrying amount [member] | July 06, 2020 [member] |  |  |  |  |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |  |  |  |  |
Borrowings | 40,527 | ¥ 4,000,000 |  |  |  |  |
Debentures [member] | Gross carrying amount [member] | July 06, 2021 [member] |  |  |  |  |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |  |  |  |  |
Borrowings | 162,109 | 16,000,000 |  |  |  |  |
Debentures [member] | Gross carrying amount [member] | Nov 13, 2020 [member] |  |  |  |  |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |  |  |  |  |
Borrowings | 303,954 | ¥ 30,000,000 |  |  |  |  |
Debentures [member] | Gross carrying amount [member] | Aug. 06, 2018 [member] |  |  |  |  |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |  |  |  |  |
Borrowings |  |  |  | 100,000 |  |  |
Debentures [member] | Gross carrying amount [member] | Mar. 29, 2018 [member] |  |  |  |  |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |  |  |  |  |
Borrowings |  |  |  | 260,000 |  |  |
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, 2016 [member] |  |  |  |  |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |  |  |  |  |
Borrowings |  |  |  | 90,000 |  |  |
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 |  |  |  | 120,000 |  |  |
Debentures [member] | Gross carrying amount [member] | Apr. 10, 2023 [member] |  |  |  |  |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |  |  |  |  |
Borrowings | 190,000 |  |  | 190,000 |  |  |
Debentures [member] | Gross carrying amount [member] | Apr. 10, 2033 [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 |  |  |  | 200,000 |  |  |
Debentures [member] | Gross carrying amount [member] | Sept. 16, 2020 [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 |  |  | 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 |  |  | 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 |  |  | 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. 28, 2036 [member] |  |  |  |  |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |  |  |  |  |
Borrowings | 70,000 |  |  | 70,000 |  |  |
Debentures [member] | Gross carrying amount [member] | Jan. 29, 2021 [member] |  |  |  |  |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |  |  |  |  |
Borrowings | 110,000 |  |  |  |  |  |
Debentures [member] | Gross carrying amount [member] | Jan. 30, 2023 [member] |  |  |  |  |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |  |  |  |  |
Borrowings | 150,000 |  |  |  |  |  |
Debentures [member] | Gross carrying amount [member] | Jan. 30, 2028 [member] |  |  |  |  |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |  |  |  |  |
Borrowings | 170,000 |  |  |  |  |  |
Debentures [member] | Gross carrying amount [member] | Jan. 30, 2038 [member] |  |  |  |  |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |  |  |  |  |
Borrowings | ₩ 70,000 |  |  |  |  |  |
Debentures [member] | Gross carrying amount [member] | Apr. 22, 2018 [member] |  |  |  |  |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |  |  |  |  |
Borrowings |  |  |  | ₩ 60,000 |  |  |

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