Investment properties, net (Details) - KRW (₩) ₩ in Millions	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Disclosure of detailed information about investment property [Line Items]
Beginning balance	₩ 284,714	₩ 353,680
Depreciation	(923)	(1,176)	₩ (678)
Others	(124,232)	(67,790)
Endings balance	159,559	284,714	353,680
Carrying Amount Other than Government Grants
Disclosure of detailed information about investment property [Line Items]
Beginning balance	284,797	353,744
Depreciation	(924)	(1,178)
Others	(124,264)	(67,769)
Endings balance	159,609	284,797	353,744
Acquisition cost
Disclosure of detailed information about investment property [Line Items]
Beginning balance	300,370
Endings balance	174,741	300,370
Accumulated depreciation
Disclosure of detailed information about investment property [Line Items]
Beginning balance	(15,573)
Endings balance	(15,132)	(15,573)
Government grants
Disclosure of detailed information about investment property [Line Items]
Beginning balance	(83)	(64)
Depreciation	1	2
Others	32	(21)
Endings balance	(50)	(83)	(64)
Investment property - Land
Disclosure of detailed information about investment property [Line Items]
Beginning balance	264,205	336,421
Depreciation	0	0
Others	(124,265)	(72,216)
Endings balance	139,940	264,205	336,421
Investment property - Land \| Carrying Amount Other than Government Grants
Disclosure of detailed information about investment property [Line Items]
Beginning balance	264,205	336,421
Others	(124,265)	(72,216)
Endings balance	139,940	264,205	336,421
Investment property - Land \| Acquisition cost
Disclosure of detailed information about investment property [Line Items]
Beginning balance	264,205
Endings balance	139,940	264,205
Investment property - Buildings
Disclosure of detailed information about investment property [Line Items]
Beginning balance	20,509	17,259
Depreciation	(923)	(1,176)
Others	33	4,426
Endings balance	19,619	20,509	17,259
Investment property - Buildings \| Carrying Amount Other than Government Grants
Disclosure of detailed information about investment property [Line Items]
Beginning balance	20,592	17,323
Depreciation	(924)	(1,178)
Others	1	4,447
Endings balance	19,669	20,592	17,323
Investment property - Buildings \| Acquisition cost
Disclosure of detailed information about investment property [Line Items]
Beginning balance	36,165
Endings balance	34,801	36,165
Investment property - Buildings \| Accumulated depreciation
Disclosure of detailed information about investment property [Line Items]
Beginning balance	(15,573)
Endings balance	(15,132)	(15,573)
Investment property - Buildings \| Government grants
Disclosure of detailed information about investment property [Line Items]
Beginning balance	(83)	(64)
Depreciation	1	2
Others	32	(21)
Endings balance	₩ (50)	₩ (83)	₩ (64)

The amount of depreciation recognised on investment property. [Refer: Depreciation and amortisation expense; Investment property]

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 40
-IssueDate 2018-01-01
-Paragraph 79
-Subparagraph d
-Clause iv
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=40&date=2018-03-01&anchor=para_79_d_iv&doctype=Standard
-URIDate 2018-03-16

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 40
-IssueDate 2018-01-01
-Paragraph 76
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=40&date=2018-03-01&anchor=para_76&doctype=Standard
-URIDate 2018-03-16

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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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- Definition

The increase (decrease) in investment property resulting from changes that the entity does not separately disclose in the same statement or note. [Refer: Investment property]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 40
-IssueDate 2018-01-01
-Paragraph 79
-Subparagraph d
-Clause viii
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=40&date=2018-03-01&anchor=para_79_d_viii&doctype=Standard
-URIDate 2018-03-16

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 40
-IssueDate 2018-01-01
-Paragraph 76
-Subparagraph g
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=40&date=2018-03-01&anchor=para_76_g&doctype=Standard
-URIDate 2018-03-16

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- Definition

Expiry date 2019-01-01: The amount of property (land or a building - or part of a building - or both) held (by the owner or by the lessee under a finance lease) to earn rentals or for capital appreciation or both, rather than for: (a) use in the production or supply of goods or services or for administrative purposes; or (b) sale in the ordinary course of business. Effective 2019-01-01: The amount of property (land or a building - or part of a building - or both) held (by the owner or by the lessee as a right-of-use asset) to earn rentals or for capital appreciation or both, rather than for: (a) use in the production or supply of goods or services or for administrative purposes; or (b) sale in the ordinary course of business.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 40
-IssueDate 2018-01-01
-Paragraph 76
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=40&date=2018-03-01&anchor=para_76&doctype=Standard
-URIDate 2018-03-16

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 40
-IssueDate 2018-01-01
-Paragraph 79
-Subparagraph d
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=40&date=2018-03-01&anchor=para_79_d&doctype=Standard
-URIDate 2018-03-16

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 1
-IssueDate 2018-01-01
-Paragraph 54
-Subparagraph b
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=1&date=2018-03-01&anchor=para_54_b&doctype=Standard
-URIDate 2018-03-16

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