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Significant Accounting Policies - Additional Information (Detail) - KRW (₩) ₩ in Millions | 12 Months Ended
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Dec. 31, 2019 | Dec. 31, 2018
Disclosure of significant accounting policies [line items] |  |
Lease term |  | Lease term is over 12 months
Description of assets which are not low value |  | Underlying assets are not low value assets
Bottom of range [member] |  |
Disclosure of significant accounting policies [line items] |  |
Useful lives of investment property, excluding land depreciated cost model | 10 years |
Top of range [member] |  |
Disclosure of significant accounting policies [line items] |  |
Useful lives of investment property, excluding land depreciated cost model | 40 years |
IFRS 16 leases [member] |  |
Disclosure of significant accounting policies [line items] |  |
Lease assets and liabilities |  | ₩ 616,759

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- Definition The statement that the lessee accounts for leases of low-value assets using the recognition exemption in paragraph 6 of IFRS 16. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 16 -IssueDate 2019-01-01 -Paragraph 60 -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=16&code=ifrs-tx-2019-en-r&anchor=para_60&doctype=Standard -URIDate 2019-03-27 + Details
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Balance Type: | na
Period Type: | duration

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- Definition 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. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 16 -IssueDate 2019-01-01 -Paragraph 60 -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=16&code=ifrs-tx-2019-en-r&anchor=para_60&doctype=Standard -URIDate 2019-03-27 + Details
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- Definition The useful life, measured as period of time, used for investment property. [Refer: Investment property] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 40 -IssueDate 2019-01-01 -Paragraph 79 -Subparagraph b -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=40&code=ifrs-tx-2019-en-r&anchor=para_79_b&doctype=Standard -URIDate 2019-03-27 + Details
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Balance Type: | na
Period Type: | duration

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- Definition Disclosure of significant accounting policies [line items] + References No definition available. + Details
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Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

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- Definition Lease assets and liabilities recognized in consolidated financial position. + References No definition available. + Details
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Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

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- Details
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- Details
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- Details
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