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Business Combination - Additional Information (Detail) ₩ in Millions, $ in Millions | Sep. 30, 2021 KRW (₩) shares | Sep. 30, 2021 USD ($) shares
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Hyundai HCN Co., Ltd [Member] |  |
Disclosure of detailed information about business combination [Line Items] |  |
Percentage of ownership interest | 100.00% |
Number of shares acquired | 7,000,000 | 7,000,000
Number of Shares Acquired Value | ₩ | ₩ 515,091 |
Epsilon Global Communications Pte. Ltd [Member] |  |
Disclosure of detailed information about business combination [Line Items] |  |
Percentage of ownership interest | 100.00% |
Number of shares acquired | 81,320,642 | 81,320,642
Number of Shares Acquired Value | $ |  | $ 135

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