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Fair Value - Summary of Fair Value Non of Financial Instruments (Detail) - KRW (₩) ₩ in Millions | Dec. 31, 2019 | Dec. 31, 2018
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Disclosure of detailed information about financial instruments [line items] |  |
Non financial assets | ₩ 4,809,091 | ₩ 4,052,094
Non financial liabilities | 20,134 | 65,066
Level 1 [Member] |  |
Disclosure of detailed information about financial instruments [line items] |  |
Non financial assets | 6,970 | 8,982
Non financial liabilities | 0 |
Level 2 [Member] |  |
Disclosure of detailed information about financial instruments [line items] |  |
Non financial assets | 1,942,555 | 1,746,915
Non financial liabilities | 20,134 | 47,125
Level 3 [Member] |  |
Disclosure of detailed information about financial instruments [line items] |  |
Non financial assets | 2,859,566 | 2,296,197
Non financial liabilities | 0 | 17,941
Financial assets at fair value through other comprehensive income [member] |  |
Disclosure of detailed information about financial instruments [line items] |  |
Non financial assets | 1,256,266 | 1,097,348
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 | 1,256,266 | 1,097,348
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 | 632,324 | 777,685
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 | 232 | 121
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 | 136,951 | 613,964
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 | 495,141 | 163,600
Other financial assets at fair value through other comprehensive income [member] |  |
Disclosure of detailed information about financial instruments [line items] |  |
Non financial assets | 557,342 | 326,157
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 | 6,738 | 8,861
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 | 508,550 | 5,760
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 | 42,054 | 311,536
Derivative financial assets for hedging [member] |  |
Disclosure of detailed information about financial instruments [line items] |  |
Non financial assets | 58,576 | 29,843
Derivative financial assets for hedging [member] | Level 1 [Member] |  |
Disclosure of detailed information about financial instruments [line items] |  |
Non financial assets | 0 |
Derivative financial assets for hedging [member] | Level 2 [Member] |  |
Disclosure of detailed information about financial instruments [line items] |  |
Non financial assets | 40,788 | 29,843
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 | 2,304,583 | 1,821,061
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 | 2,304,583 | 1,821,061
Other financial liabilities at fair value through profit or loss [member] |  |
Disclosure of detailed information about financial instruments [line items] |  |
Non financial liabilities | 38 | 7,758
Other financial liabilities at fair value through profit or loss [member] | Level 1 [Member] |  |
Disclosure of detailed information about financial instruments [line items] |  |
Non financial liabilities | 0 |
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 | 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 | 0 | 7,758
Derivative financial liabilities for hedging [member] |  |
Disclosure of detailed information about financial instruments [line items] |  |
Non financial liabilities | 20,096 | 57,308
Derivative financial liabilities for hedging [member] | Level 1 [Member] |  |
Disclosure of detailed information about financial instruments [line items] |  |
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 | 20,096 | 47,125
Derivative financial liabilities for hedging [member] | Level 3 [Member] |  |
Disclosure of detailed information about financial instruments [line items] |  |
Non financial liabilities | ₩ 0 | ₩ 10,183

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