The amount of additional allowance for credit losses of financial assets recognised in profit or loss. [Refer: Allowance account for credit losses of financial assets]

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- Definition

The amount of instruments representing indebtedness held by the entity.

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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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-IssueDate 2017-01-01
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The amount of instruments held by the entity that provide evidence of a residual interest in the assets of another entity after deducting all of its liabilities.

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The amount of non-derivative financial assets that are designated as available for sale or are not classified as (a) loans and receivables; (b) held-to-maturity investments; or (c) financial assets at fair value through profit or loss. [Refer: Derivative financial assets; Financial assets at fair value through profit or loss; Held-to-maturity investments]

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Note Expiry date 2018-01-01
-Name IFRS
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-IssueDate 2017-01-01
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The amount of a hedging instrument, recognised as an asset. [Refer: Hedging instruments [member]]

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Note Effective 2018-01-01
-Name IFRS
-Number 7
-IssueDate 2017-01-01
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The amount of a hedging instrument, recognised as a liability. [Refer: Hedging instruments [member]]

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The amount of non-derivative financial assets with fixed or determinable payments that are not quoted in an active market, other than: (a) those that the entity intends to sell immediately or in the near term, which shall be classified as held for trading, and those that the entity, upon initial recognition, designates as at fair value through profit or loss; (b) those that the entity, upon initial recognition, designates as available for sale; or (c) those for which the holder may not recover substantially all of its initial investment, other than because of credit deterioration, which shall be classified as available for sale. An interest acquired in a pool of assets that are not loans or receivables (for example, an interest in a mutual fund or a similar fund) is not a loan or receivable. [Refer: Derivative financial assets]

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The statement that the lessee accounts for leases of low-value assets using the recognition exemption in paragraph 6 of IFRS 16.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Note Effective 2019-01-01
-Name IFRS
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The statement that the lessee accounts for short-term leases using the recognition exemption in paragraph 6 of IFRS 16. Short-term lease is a lease that, at the commencement date, has a lease term of 12 months or less. A lease that contains a purchase option is not a short-term lease.

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The useful lives or depreciation rates used for investment property. [Refer: Investment property]

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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-IssueDate 2017-01-01
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Cumulative effect of change in operating income and expenses under modified retrospective method.

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No definition available.

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Disclosure of significant accounting policies [line items]

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Significant Accounting Policies - Additional Information (Detail) - KRW (₩) ₩ in Millions		12 Months Ended
	Jan. 01, 2018	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Disclosure of significant accounting policies [line items]
Short-term lease description		A lease term of 12 months or less at the commencement date
Low value assets description		Underlying assets below $ 5,000
Loans and receivables		₩ 9,653,443
Financial assets available-for-sales		380,953	₩ 404,774	₩ 360,037
Debt instruments held with entity		9,653,594
Loss allowance recognized for credit losses of financial assets		523,799
Hedging instrument, assets		7,389
Hedging instrument, liabilities		₩ 93,770
Useful lives of investment property, excluding land depreciated cost model		10 to 40 Years
Minimum [member] \| Increase (decrease) due to changes in accounting policy required by IFRSs [member]
Disclosure of significant accounting policies [line items]
Cumulative effect of change in operating income and expenses under modified retrospective method	₩ 900,000
Maximum [member] \| Increase (decrease) due to changes in accounting policy required by IFRSs [member]
Disclosure of significant accounting policies [line items]
Cumulative effect of change in operating income and expenses under modified retrospective method	₩ 1,100,000
Available-for-sale [member]
Disclosure of significant accounting policies [line items]
Equity instruments held with entity		₩ 371,054
Loans and receivables [member]
Disclosure of significant accounting policies [line items]
Debt instruments held with entity		9,653,443
Held-to-maturity financial assets [member]
Disclosure of significant accounting policies [line items]
Debt instruments held with entity		₩ 151