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Intangible Assets - Summary of Goodwill Allocated to Each Cash-Generation Unit (Detail) ₩ in Millions | Dec. 31, 2017 KRW (₩)
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Disclosure of detailed information about intangible assets [line items] |
Goodwill | ₩ 168,880
Telecom Wireless Business [member] | Marketing [Member] |
Disclosure of detailed information about intangible assets [line items] |
Goodwill | 65,057
BC Card Co., Ltd. [member] | Finance [member] |
Disclosure of detailed information about intangible assets [line items] |
Goodwill | 41,234
PlayD Co., Ltd. (N Search Marketing Co., Ltd.) [Member] | Others [member] |
Disclosure of detailed information about intangible assets [line items] |
Goodwill | 42,745
Genie Music Corporation (KT Music Corporation) and others [Member] | Others [member] |
Disclosure of detailed information about intangible assets [line items] |
Goodwill | ₩ 19,844

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