Transactions with Related Parties - Summary of Transactions with Related Parties (Details) - GungHo Online Entertainment, Inc [Member] - KRW (₩) ₩ in Millions	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Disclosure Of Transactions Between Related Parties [Line Items]
Sales	₩ 21,833	₩ 27,484	₩ 10,516
Purchase	₩ 211	₩ 60	₩ 3

Line items represent concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes of the table.

No definition available.

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- Definition

The amount of goods purchased by the entity in related party transactions. [Refer: Related parties [member]]

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The amount of revenue arising from the sale of goods in related party transactions. [Refer: Revenue; Related parties [member]]

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