Reconciliation of changes in fair value measurement, assets (Details) - At fair value - Level 3 - KRW (₩) ₩ in Millions	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017
Financial assets available-for-sale, category [Member]
Reconciliation of changes in fair value measurement, assets [Line Items]
Beginning balance	₩ 173,298	₩ 269,461
Changes in fair value measurement, assets
Effect of change in accounting policy	0	0
Acquisition	0	0
Reclassified category	0	(92,128)
Valuation	0	(6,201)
Disposal	0	0
Foreign currency translation	0	2,166
Ending balance	0	173,298
Financial assets at fair value through profit or loss, category [Member]
Reconciliation of changes in fair value measurement, assets [Line Items]
Beginning balance	0	0
Changes in fair value measurement, assets
Effect of change in accounting policy	5,038	0
Acquisition	0	0
Reclassified category	0	0
Valuation	14	0
Disposal	0	0
Foreign currency translation	0	0
Ending balance	5,052	0
Financial assets at fair value through other comprehensive income [Member]
Reconciliation of changes in fair value measurement, assets [Line Items]
Beginning balance	0	0
Changes in fair value measurement, assets
Effect of change in accounting policy	197,450	0
Acquisition	0	0
Reclassified category	0	0
Valuation	(11,744)	0
Disposal	(326)	0
Foreign currency translation	4,059	0
Ending balance	₩ 189,439	₩ 0

No definition available.

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- Definition

The gains (losses) recognised in other comprehensive income on the fair value measurement of assets. [Refer: At fair value [member]; Other comprehensive income]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 13
-IssueDate 2018-01-01
-Paragraph 93
-Subparagraph e
-Clause ii
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=13&date=2018-03-01&anchor=para_93_e_ii&doctype=Standard
-URIDate 2018-03-16

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- Definition

The increase in the fair value measurement of assets resulting from purchases of those assets. [Refer: At fair value [member]]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 13
-IssueDate 2018-01-01
-Paragraph 93
-Subparagraph e
-Clause iii
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=13&date=2018-03-01&anchor=para_93_e_iii&doctype=Standard
-URIDate 2018-03-16

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- Definition

The decrease in the fair value measurement of assets resulting from sales. [Refer: At fair value [member]]

+ References

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- Definition

The amount of transfers of assets into Level 3 of the fair value hierarchy. [Refer: Level 3 of fair value hierarchy [member]]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 13
-IssueDate 2018-01-01
-Paragraph 93
-Subparagraph e
-Clause iv
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=13&date=2018-03-01&anchor=para_93_e_iv&doctype=Standard
-URIDate 2018-03-16

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- References

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- References

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- References

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