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Trade and Other Receivables - Summary of Changes in Summary of Changes in Provision for Impairment (Detail) - KRW (₩) ₩ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Trade receivables [member]
Disclosure of financial assets [line items]
Beginning balance	₩ 295,319	₩ 359,924
Provision	89,097	24,596
Write-off or transfer out	(60,598)	(90,513)
Changes in the scope of consolidation	3,211
Others	286	1,312
Ending balance	327,315	295,319
Other receivables [member]
Disclosure of financial assets [line items]
Beginning balance	83,680	93,822
Provision	50,860	35,597
Reversal	(890)	(475)
Write-off or transfer out	(25,067)	(44,108)
Changes in the scope of consolidation	87,614
Others	8,407	(1,156)
Ending balance	₩ 204,604	₩ 83,680

X

- Definition

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]

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Note Expiry date 2021-01-01
-Name IFRS
-Number 7
-IssueDate 2020-01-01
-Paragraph 16
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=7&code=ifrs-tx-2017-en-b&anchor=para_16&doctype=Standard&book=b
-URIDate 2020-01-01

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X

- Definition

The amount of an allowance account used to record impairments to financial assets due to credit losses. [Refer: Financial assets]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Note Expiry date 2021-01-01
-Name IFRS
-Number 7
-IssueDate 2020-01-01
-Paragraph 16
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=7&code=ifrs-tx-2017-en-b&anchor=para_16&doctype=Standard&book=b
-URIDate 2020-01-01

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- Definition

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

No definition available.

+ Details

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X

- Definition

The increase (decrease) in allowance account for credit losses of financial assets resulting from changes that the entity does not separately disclose in the same statement or note. [Refer: Allowance account for credit losses of financial assets]

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Note Expiry date 2021-01-01
-Name IFRS
-Number 7
-IssueDate 2020-01-01
-Paragraph 16
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=7&code=ifrs-tx-2017-en-b&anchor=para_16&doctype=Standard&book=b
-URIDate 2020-01-01

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X

- Definition

The decrease in an allowance account for credit losses of financial assets resulting from the reversal of impairment. [Refer: Allowance account for credit losses of financial assets]

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Note Expiry date 2021-01-01
-Name IFRS
-Number 7
-IssueDate 2020-01-01
-Paragraph 16
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=7&code=ifrs-tx-2017-en-b&anchor=para_16&doctype=Standard&book=b
-URIDate 2020-01-01

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- Definition

Allowance for doubtful accounts changes in the scope of consolidation.

+ References

No definition available.

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X

- Definition

Write Off Or Transfer Out Of Allowance Account For Credit Losses Of Financial Assets.

+ References

No definition available.

+ Details

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X

- Details

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X

- Details

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