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Fair Value - Summary of Fair Value Non of Financial Instruments (Detail) - KRW (₩) ₩ in Millions | Dec. 31, 2020 | Dec. 31, 2019
--- | --- | ---
Disclosure of detailed information about financial instruments [line items] |  |
Non financial assets | ₩ 4,840,220 | ₩ 4,809,091
Non financial liabilities | 130,611 | 20,134
Level 1 [Member] |  |
Disclosure of detailed information about financial instruments [line items] |  |
Non financial assets | 52,055 | 6,970
Non financial liabilities | 0 |
Level 2 [Member] |  |
Disclosure of detailed information about financial instruments [line items] |  |
Non financial assets | 1,659,385 | 1,942,555
Non financial liabilities | 123,780 | 20,134
Level 3 [Member] |  |
Disclosure of detailed information about financial instruments [line items] |  |
Non financial assets | 3,128,780 | 2,859,566
Non financial liabilities | 6,831 | 0
Financial assets at fair value through other comprehensive income [member] |  |
Disclosure of detailed information about financial instruments [line items] |  |
Non financial assets | 1,118,619 | 1,256,266
Financial assets at fair value through other comprehensive income [member] | Level 1 [Member] |  |
Disclosure of detailed information about financial instruments [line items] |  |
Non financial assets |  | 0
Financial assets at fair value through other comprehensive income [member] | Level 2 [Member] |  |
Disclosure of detailed information about financial instruments [line items] |  |
Non financial assets | 1,118,619 | 1,256,266
Financial assets at fair value through other comprehensive income [member] | Level 3 [Member] |  |
Disclosure of detailed information about financial instruments [line items] |  |
Non financial assets |  | 0
Financial assets at fair value through profit or loss [member] |  |
Disclosure of detailed information about financial instruments [line items] |  |
Non financial assets | 809,919 | 632,324
Financial assets at fair value through profit or loss [member] | Level 1 [Member] |  |
Disclosure of detailed information about financial instruments [line items] |  |
Non financial assets | 46,449 | 232
Non financial liabilities | 0 |
Financial assets at fair value through profit or loss [member] | Level 2 [Member] |  |
Disclosure of detailed information about financial instruments [line items] |  |
Non financial assets | 330,961 | 136,951
Financial assets at fair value through profit or loss [member] | Level 3 [Member] |  |
Disclosure of detailed information about financial instruments [line items] |  |
Non financial assets | 432,509 | 495,141
Non financial liabilities |  | 0
Other financial assets at fair value through other comprehensive income [member] |  |
Disclosure of detailed information about financial instruments [line items] |  |
Non financial assets | 258,516 | 557,342
Other financial assets at fair value through other comprehensive income [member] | Level 1 [Member] |  |
Disclosure of detailed information about financial instruments [line items] |  |
Non financial assets | 5,606 | 6,738
Other financial assets at fair value through other comprehensive income [member] | Level 2 [Member] |  |
Disclosure of detailed information about financial instruments [line items] |  |
Non financial assets | 202,121 | 508,550
Other financial assets at fair value through other comprehensive income [member] | Level 3 [Member] |  |
Disclosure of detailed information about financial instruments [line items] |  |
Non financial assets | 50,789 | 42,054
Derivative financial assets for hedging [member] |  |
Disclosure of detailed information about financial instruments [line items] |  |
Non financial assets | 7,684 | 58,576
Derivative financial assets for hedging [member] | Level 2 [Member] |  |
Disclosure of detailed information about financial instruments [line items] |  |
Non financial assets | 7,684 | 40,788
Derivative financial assets for hedging [member] | Level 3 [Member] |  |
Disclosure of detailed information about financial instruments [line items] |  |
Non financial assets |  | 17,788
Investment Properties [member] |  |
Disclosure of detailed information about financial instruments [line items] |  |
Non financial assets | 2,645,482 | 2,304,583
Investment Properties [member] | Level 1 [Member] |  |
Disclosure of detailed information about financial instruments [line items] |  |
Non financial assets |  | 0
Investment Properties [member] | Level 2 [Member] |  |
Disclosure of detailed information about financial instruments [line items] |  |
Non financial assets |  | 0
Investment Properties [member] | Level 3 [Member] |  |
Disclosure of detailed information about financial instruments [line items] |  |
Non financial assets | 2,645,482 | 2,304,583
Other financial liabilities at fair value through profit or loss [member] |  |
Disclosure of detailed information about financial instruments [line items] |  |
Non financial liabilities | 2,682 | 38
Other financial liabilities at fair value through profit or loss [member] | Level 2 [Member] |  |
Disclosure of detailed information about financial instruments [line items] |  |
Non financial liabilities | 45 | 38
Other financial liabilities at fair value through profit or loss [member] | Level 3 [Member] |  |
Disclosure of detailed information about financial instruments [line items] |  |
Non financial liabilities | 2,637 |
Derivative financial liabilities for hedging [member] |  |
Disclosure of detailed information about financial instruments [line items] |  |
Non financial liabilities | 127,929 | 20,096
Derivative financial liabilities for hedging [member] | Level 1 [Member] |  |
Disclosure of detailed information about financial instruments [line items] |  |
Non financial assets |  | 0
Non financial liabilities | 0 |
Derivative financial liabilities for hedging [member] | Level 2 [Member] |  |
Disclosure of detailed information about financial instruments [line items] |  |
Non financial liabilities | 123,735 | 20,096
Derivative financial liabilities for hedging [member] | Level 3 [Member] |  |
Disclosure of detailed information about financial instruments [line items] |  |
Non financial liabilities | ₩ 4,194 | ₩ 0

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