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Business Combination - Schedule of Fair Value of Purchase Consideration from Business Combination (Parenthetical) (Detail) ₩ in Millions | 12 Months Ended
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Dec. 31, 2018 KRW (₩) shares
KT MOS Bukbu Co.,Ltd. [member] |
Disclosure of detailed information about business combination [Line Items] |
Number of ordinary shares previously held | shares | 93,994
KTMOS Nambu Co.,Ltd. [member] |
Disclosure of detailed information about business combination [Line Items] |
Number of ordinary shares previously held | shares | 65,831
GENIE Music Corporation K T Music Corporation [member] |
Disclosure of detailed information about business combination [Line Items] |
Fair value of equity instruments newly issued | ₩ | ₩ 50,948
Number of ordinary shares issued | 8,992,685
Share issuance cost | ₩ | ₩ 31

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