Financial Risk Management - Changes of Financial Assets Classified as Level 3 (Detail) ₩ in Millions	12 Months Ended
Dec. 31, 2018 KRW (₩)
Disclosure of fair value measurement of assets [line items]
Balance at beginning	₩ 33,428,669
Balance at ending	42,369,111
Level 3 [member]
Disclosure of fair value measurement of assets [line items]
Balance at beginning	320,159
Gain for the period	7,708
OCI	(51,743)
Acquisition	34,042
Disposal	(135,885)
Balance at ending	375,092
Level 3 [member] \| Impact of adopting IFRS 9 [member]
Disclosure of fair value measurement of assets [line items]
Impact of adopting IFRS 9	200,811
Financial assets at fair value through profit or loss [member] \| Level 3 [member]
Disclosure of fair value measurement of assets [line items]
Balance at beginning	222,257
Financial assets at fair value through profit or loss [member] \| Level 3 [member] \| Impact of adopting IFRS 9 [member]
Disclosure of fair value measurement of assets [line items]
Impact of adopting IFRS 9	(222,257)
Available- for-sale financial assets [Member] \| Level 3 [member]
Disclosure of fair value measurement of assets [line items]
Balance at beginning	97,902
Available- for-sale financial assets [Member] \| Level 3 [member] \| Impact of adopting IFRS 9 [member]
Disclosure of fair value measurement of assets [line items]
Impact of adopting IFRS 9	(97,902)
FVTPL [member] \| Level 3 [member]
Disclosure of fair value measurement of assets [line items]
Gain for the period	7,708
OCI	732
Acquisition	18,732
Disposal	(128,713)
Reclassification	(165,600)
Balance at ending	124,374
FVTPL [member] \| Level 3 [member] \| Impact of adopting IFRS 9 [member]
Disclosure of fair value measurement of assets [line items]
Impact of adopting IFRS 9	391,515
Financial assets at FVOCI [member] \| Level 3 [member]
Disclosure of fair value measurement of assets [line items]
OCI	(52,475)
Acquisition	15,310
Disposal	(7,172)
Reclassification	165,600
Balance at ending	250,718
Financial assets at FVOCI [member] \| Level 3 [member] \| Impact of adopting IFRS 9 [member]
Disclosure of fair value measurement of assets [line items]
Impact of adopting IFRS 9	₩ 129,455

The amount that is reclassified when the entity changes classification or presentation in its financial statements.

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The amount of resources: (a) controlled by the entity as a result of past events; and (b) from which future economic benefits are expected to flow to the entity.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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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.

+ References

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The gains (losses) recognised in other comprehensive income on the fair value measurement of assets. [Refer: At fair value [member]; Other comprehensive income]

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The gains (losses) recognised in profit or loss on the fair value measurement of assets. [Refer: At fair value [member]]

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The increase in the fair value measurement of assets resulting from purchases of those assets. [Refer: At fair value [member]]

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The decrease in the fair value measurement of assets resulting from sales. [Refer: At fair value [member]]

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- Definition

Reclassification fair value measurement assets.

+ References

No definition available.

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