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Investments in Associates and Joint Ventures - Summary of Reconciliation of Carrying Amount of Interests in the Associates and Joint Ventures (Parenthetical) (Detail)	12 Months Ended
	Dec. 31, 2019
K Bank Inc. [member]
Disclosure Of Associates And Joint Ventures [Line Items]
Percentage of non-voting convertible stock are excluded	12.10%

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- Definition

Proportion of non-voting rights in associate.

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- Details

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