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Borrowings - Summary of Long-term Borrowings (Detail) $ in Thousands, ₩ in Millions | 12 Months Ended |  |
--- | --- | --- | ---
Dec. 31, 2019 KRW (₩) | Dec. 31, 2019 USD ($) | Dec. 31, 2018 KRW (₩) | Dec. 31, 2018 USD ($)
Disclosure of detailed information about borrowings [line items] |  |  |  |
Borrowings | ₩ 7,298,867 |  | ₩ 6,648,293 |
Total | ₩ 6,113,142 |  | 5,279,812 |
Shinhan Bank [member] | Vessel facility loans [member] |  |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |  |
Annual interest rates adjustment rate | 1.908% | 1.908% |  |
Long-term borrowings [member] |  |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |  |
Borrowings | ₩ 190,780 |  | 546,090 |
Less: Current portion | (50,192) |  | (394,927) |
Total | 140,588 |  | 151,163 |
Long-term borrowings [member] | General loans [member] |  |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |  |
Borrowings | ₩ 30,000 |  | 30,000 |
Long-term borrowings [member] | Export-Import Bank of Korea [member] | Inter-Korean Cooperation Fund [member] |  |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |  |
Annual interest rates | 1.50% | 1.50% |  |
Borrowings | ₩ 3,454 |  | 3,948 |
Long-term borrowings [member] | Industrial Bank of Korea [member] | General loans [member] |  |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |  |
Annual interest rates | 2.98% | 2.98% |  |
Borrowings | ₩ 6,000 |  |  |
Long-term borrowings [member] | Shinhan Bank [member] | General loans [member] |  |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |  |
Annual interest rates | 2.81% | 2.81% |  |
Borrowings | ₩ 5,000 |  | 5,000 |
Long-term borrowings [member] | Shinhan Bank [member] | Facility loans [member] |  |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |  |
Annual interest rates | 3.06% | 3.06% |  |
Borrowings | ₩ 30,008 | $ 25,918 | 30,000 |
Long-term borrowings [member] | Shinhan Bank [member] | Vessel facility loans [member] |  |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |  |
Annual interest rates description | LIBOR(3M)+0.706% |  |  |
Annual interest rates adjustment rate | 0.706% | 0.706% |  |
Borrowings | ₩ 3,473 | $ 3,000 | 10,063 | $ 9,000
Long-term borrowings [member] | Standard Charted Bank [member] | General loans [member] |  |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |  |
Borrowings |  |  | 6,000 |
Long-term borrowings [member] | NongHyup Bank [member] | General loans [member] |  |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |  |
Borrowings |  |  | 8,000 |
Long-term borrowings [member] | NongHyup Bank [member] | Facility loans [member] |  |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |  |
Annual interest rates | 2.00% | 2.00% |  |
Borrowings | ₩ 79 |  | 104 |
Long-term borrowings [member] | Korea Development Bank [member] |  |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |  |
Annual interest rates | 3.31% | 3.31% |  |
Long-term borrowings [member] | Korea Development Bank [member] | General loans [member] |  |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |  |
Annual interest rates | 3.02% | 3.02% |  |
Borrowings | ₩ 10,000 |  | 10,000 |
Long-term borrowings [member] | NH Investment & Security Co., Ltd. [member] | Commercial papers [member] |  |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |  |
Borrowings |  |  | 300,000 |
Long-term borrowings [member] | Other Financial Instruments [member] | Redeemable convertible preferred stock [member] |  |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |  |
Annual interest rates | 1.00% | 1.00% |  |
Borrowings | ₩ 950 |  | 950 |
Long-term borrowings [member] | Other Financial Instruments [member] | Kookmin Bank and other [member] |  |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |  |
Borrowings | ₩ 101,816 | $ 87,940 | ₩ 142,025 | $ 127,023

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