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Related Party Transactions - Summary of Significant Transactions with Related Parties (Detail) - KRW (₩) ₩ in Millions | 12 Months Ended
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Dec. 31, 2021 | Dec. 31, 2020 | Dec. 31, 2019
Disclosure of transactions between related parties [line items] |  |  |
Sales | ₩ 296,186 | ₩ 18,765 | ₩ 23,416
Purchases | 37,774 | 18,499 | 19,055
K-Realty CR-REITs No.1 [member] |  |  |
Disclosure of transactions between related parties [line items] |  |  |
Sales | 238,847 | 2,298 | 1,302
Purchases | 1,308 |  |
Others [member] |  |  |
Disclosure of transactions between related parties [line items] |  |  |
Sales | 28,092 | 809 |
Purchases | 21,302 | 10,272 |
K Bank [member] |  |  |
Disclosure of transactions between related parties [line items] |  |  |
Sales | 24,247 | 15,658 | 17,815
Purchases | 15,164 | ₩ 8,227 | 8,524
NgeneBio [member] |  |  |
Disclosure of transactions between related parties [line items] |  |  |
Sales |  |  | 1,498
Purchases |  |  | 10,531
K-Realty CR-REITs No.10 [member] |  |  |
Disclosure of transactions between related parties [line items] |  |  |
Sales |  |  | ₩ 2,801
IGIS Professional Investors Private Investment Real Estate Investment LLC No.395 [Member] |  |  |
Disclosure of transactions between related parties [line items] |  |  |
Sales | 5,000 |  |
Purchases | ₩ 0 |  |

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