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Investment Properties - Summary of Investment Properties (Detail) - KRW (₩) ₩ in Millions | 12 Months Ended
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Dec. 31, 2017 | Dec. 31, 2016
Disclosure of detailed information about investment property [line items] |  |
Beginning balance | ₩ 1,148,044 | ₩ 1,102,070
Acquisition | 48,850 | 160,606
Disposal/Abandonment | (9,927) | (7,639)
Depreciation | (47,295) | (43,575)
Transfer from (to) property, plant and equipment | (61,472) |
Transfer |  | (63,418)
Transfer and others | (11,613) |
Ending balance | 1,189,531 | 1,148,044
Gross carrying amount [member] |  |
Disclosure of detailed information about investment property [line items] |  |
Beginning balance | 1,501,400 | 1,426,234
Ending balance | 1,590,018 | 1,501,400
Accumulated Depreciation and Amortisation [Member] |  |
Disclosure of detailed information about investment property [line items] |  |
Beginning balance | (353,356) | (324,164)
Ending balance | (400,487) | (353,356)
Land [member] |  |
Disclosure of detailed information about investment property [line items] |  |
Beginning balance | 302,750 | 340,790
Acquisition |  | 51
Disposal/Abandonment | (3,493) | (5,837)
Transfer from (to) property, plant and equipment | (64,449) |
Transfer |  | (32,254)
Transfer and others | (6,916) |
Ending balance | 356,790 | 302,750
Land [member] | Gross carrying amount [member] |  |
Disclosure of detailed information about investment property [line items] |  |
Beginning balance | 302,750 | 340,790
Ending balance | 358,358 | 302,750
Land [member] | Accumulated Depreciation and Amortisation [Member] |  |
Disclosure of detailed information about investment property [line items] |  |
Ending balance | (1,568) |
Buildings [member] |  |
Disclosure of detailed information about investment property [line items] |  |
Beginning balance | 766,529 | 687,072
Acquisition | 775 | 417
Disposal/Abandonment | (6,434) | (1,802)
Depreciation | (47,295) | (43,575)
Transfer from (to) property, plant and equipment | 1,793 |
Transfer |  | 124,417
Transfer and others | 80,986 |
Ending balance | 792,768 | 766,529
Buildings [member] | Gross carrying amount [member] |  |
Disclosure of detailed information about investment property [line items] |  |
Beginning balance | 1,119,885 | 1,011,236
Ending balance | 1,191,687 | 1,119,885
Buildings [member] | Accumulated Depreciation and Amortisation [Member] |  |
Disclosure of detailed information about investment property [line items] |  |
Beginning balance | (353,356) | (324,164)
Ending balance | (398,919) | (353,356)
Construction-in-progress [member] |  |
Disclosure of detailed information about investment property [line items] |  |
Beginning balance | 78,765 | 74,208
Acquisition | 48,075 | 160,138
Transfer from (to) property, plant and equipment | 1,184 |
Transfer |  | (155,581)
Transfer and others | (85,683) |
Ending balance | 39,973 | 78,765
Construction-in-progress [member] | Gross carrying amount [member] |  |
Disclosure of detailed information about investment property [line items] |  |
Beginning balance | 78,765 | 74,208
Ending balance | ₩ 39,973 | ₩ 78,765

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- Definition The increase in investment property resulting from acquisitions through business combinations. [Refer: Business combinations [member]; Investment property] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 40 -IssueDate 2017-01-01 -Paragraph 76 -Subparagraph b -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=40&date=2017-03-01&anchor=para_76_b&doctype=Standard -URIDate 2017-03-09 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 40 -IssueDate 2017-01-01 -Paragraph 79 -Subparagraph d -Clause ii -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=40&date=2017-03-01&anchor=para_79_d_ii&doctype=Standard -URIDate 2017-03-09 + Details
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- Definition The amount of depreciation recognised on investment property. [Refer: Depreciation and amortisation expense; Investment property] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 40 -IssueDate 2017-01-01 -Paragraph 79 -Subparagraph d -Clause iv -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=40&date=2017-03-01&anchor=para_79_d_iv&doctype=Standard -URIDate 2017-03-09 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 40 -IssueDate 2017-01-01 -Paragraph 76 -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=40&date=2017-03-01&anchor=para_76&doctype=Standard -URIDate 2017-03-09 + Details
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- Definition The increase (decrease) in property, plant and equipment resulting from transfers. [Refer: Property, plant and equipment] + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Name IAS -Number 16 -IssueDate 2017-01-01 -Paragraph 73 -Subparagraph e -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=16&date=2017-03-01&anchor=para_73_e&doctype=Standard -URIDate 2017-03-09 + Details
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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 2017-01-01 -Paragraph 76 -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=40&date=2017-03-01&anchor=para_76&doctype=Standard -URIDate 2017-03-09 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 40 -IssueDate 2017-01-01 -Paragraph 79 -Subparagraph d -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=40&date=2017-03-01&anchor=para_79_d&doctype=Standard -URIDate 2017-03-09 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 1 -IssueDate 2017-01-01 -Paragraph 54 -Subparagraph b -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=1&date=2017-03-01&anchor=para_54_b&doctype=Standard -URIDate 2017-03-09 + Details
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- Definition The amount transferred from investment property under construction or development to completed investment property. [Refer: Investment property] + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Name IAS -Number 40 -IssueDate 2017-01-01 -Paragraph 76 -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=40&date=2017-03-01&anchor=para_76&doctype=Standard -URIDate 2017-03-09 Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Name IAS -Number 40 -IssueDate 2017-01-01 -Paragraph 79 -Subparagraph d -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=40&date=2017-03-01&anchor=para_79_d&doctype=Standard -URIDate 2017-03-09 + Details
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- Definition Disposal and Abandonment, investment property + References No definition available. + Details
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- Definition Transfer from investment property under construction or development, investment property and other. + References No definition available. + Details
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