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Significant Accounting Policies - Additional Information (Detail) ₩ in Millions	12 Months Ended
	Dec. 31, 2020 KRW (₩)	Dec. 31, 2020 SGD ($)	Dec. 31, 2020 USD ($)	Dec. 31, 2019 KRW (₩)
Disclosure of significant accounting policies [line items]
Borrowing	₩ 7,316,298	$ 284,000,000	$ 519,598,989	₩ 7,298,867
Notional amount		$ 284,000,000	$ 519,598,989
Derecognition of financial liabilities, percent	10.00%
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

X

- Definition

The amount of outstanding funds that the entity is obligated to repay.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name IAS
-Number 1
-IssueDate 2020-01-01
-Paragraph 55
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-URIDate 2020-01-01

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X

- Definition

The nominal or face amount of a financial instrument, used to calculate payments made on that instrument.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name IAS
-Number 1
-IssueDate 2020-01-01
-Paragraph 112
-Subparagraph c
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X

- 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 2020-01-01
-Paragraph 79
-Subparagraph b
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=40&code=ifrs-tx-2020-en-r&anchor=para_79_b&doctype=Standard
-URIDate 2020-01-01

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X

- Definition

Percentage of fees related to te derecognition of financial liabilities.

+ References

No definition available.

+ Details

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X

- Definition

Disclosure of significant accounting policies [line items]

+ References

No definition available.

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