Assets Held for Sale - Additional Information (Detail) - KRW (₩) ₩ in Millions	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Disclosure Of Assets Held For Sale [Line Items]
Proceeds from Assets held for Sale	₩ 83,241	₩ 28,834	₩ 9,842
Non-current assets held for sale [member]
Disclosure Of Assets Held For Sale [Line Items]
Impairment loss	0
Proceeds from Assets held for Sale	₩ 82,865

The amount recognised as a reduction of the carrying amount of an asset or cash-generating unit to its recoverable amount. [Refer: Carrying amount [member]]

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 36
-IssueDate 2020-01-01
-Paragraph 130
-Subparagraph b
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=36&code=ifrs-tx-2020-en-r&anchor=para_130_b&doctype=Standard
-URIDate 2020-01-01

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 36
-IssueDate 2020-01-01
-Paragraph 130
-Subparagraph d
-Clause ii
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=36&code=ifrs-tx-2020-en-r&anchor=para_130_d_ii&doctype=Standard
-URIDate 2020-01-01

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Balance Type:	debit
Period Type:	duration