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Borrowings - Summary of Short-term Borrowing (Detail) - KRW (₩) ₩ in Millions | Dec. 31, 2018 | Dec. 31, 2017
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Disclosure of detailed information about borrowings [line items] |  |
Short-term borrowings | ₩ 92,614 | ₩ 128,300
NongHyup Bank [member] |  |
Disclosure of detailed information about borrowings [line items] |  |
Short-term borrowings | 15,000 |
Shinhan Bank [member] |  |
Disclosure of detailed information about borrowings [line items] |  |
Short-term borrowings | 59,800 | 113,300
Sinhan Bank, Indonesia [member] |  |
Disclosure of detailed information about borrowings [line items] |  |
Short-term borrowings | 614 |
Korea Development Bank [member] |  |
Disclosure of detailed information about borrowings [line items] |  |
Short-term borrowings | 16,200 | 12,000
SooHyup Bank [member] |  |
Disclosure of detailed information about borrowings [line items] |  |
Short-term borrowings | ₩ 1,000 | ₩ 3,000
Short-term borrowings [member] | NongHyup Bank [member] |  |
Disclosure of detailed information about borrowings [line items] |  |
Annual interest rates | 3.78% |
Short-term borrowings [member] | Shinhan Bank [member] | Bottom of range [member] |  |
Disclosure of detailed information about borrowings [line items] |  |
Annual interest rates | 3.70% |
Short-term borrowings [member] | Shinhan Bank [member] | Top of range [member] |  |
Disclosure of detailed information about borrowings [line items] |  |
Annual interest rates | 4.72% |
Short-term borrowings [member] | Sinhan Bank, Indonesia [member] |  |
Disclosure of detailed information about borrowings [line items] |  |
Annual interest rates | 8.90% |
Short-term borrowings [member] | Korea Development Bank [member] | Bottom of range [member] |  |
Disclosure of detailed information about borrowings [line items] |  |
Annual interest rates | 2.50% |
Short-term borrowings [member] | Korea Development Bank [member] | Top of range [member] |  |
Disclosure of detailed information about borrowings [line items] |  |
Annual interest rates | 4.35% |
Short-term borrowings [member] | SooHyup Bank [member] |  |
Disclosure of detailed information about borrowings [line items] |  |
Annual interest rates | 4.57% |

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