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Financial Risk Management - Summary of Maximum Exposure to Credit Risk (Detail) - KRW (₩) ₩ in Millions | Dec. 31, 2017 | Dec. 31, 2016
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Disclosure of detailed information about financial instruments [Line Items] |  |
Maximum exposure to credit risk | ₩ 10,070,273 | ₩ 9,975,310
Cash equivalents(except cash on hand) [Member] |  |
Disclosure of detailed information about financial instruments [Line Items] |  |
Maximum exposure to credit risk | 1,926,620 | 2,875,383
Trade and other receivables [Member] |  |
Disclosure of detailed information about financial instruments [Line Items] |  |
Maximum exposure to credit risk | 6,643,115 | 6,036,363
Financial assets at fair value through profit or loss [member] |  |
Disclosure of detailed information about financial instruments [Line Items] |  |
Maximum exposure to credit risk | 5,813 | 6,277
Derivative used for hedging [Member] |  |
Disclosure of detailed information about financial instruments [Line Items] |  |
Maximum exposure to credit risk | 7,389 | 227,318
Time deposits and others [Member] |  |
Disclosure of detailed information about financial instruments [Line Items] |  |
Maximum exposure to credit risk | 1,333,317 | 716,769
Available-for-sale [member] |  |
Disclosure of detailed information about financial instruments [Line Items] |  |
Maximum exposure to credit risk | 9,899 | 26,684
Held-to-maturity financial assets [member] |  |
Disclosure of detailed information about financial instruments [Line Items] |  |
Maximum exposure to credit risk | 151 | 30,143
Financial guarantee contracts [Member] |  |
Disclosure of detailed information about financial instruments [Line Items] |  |
Maximum exposure to credit risk | ₩ 143,969 | ₩ 56,373

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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 amount that best represents the maximum exposure to credit risk without taking into account any collateral held or other credit enhancements (for example, netting agreements that do not qualify for offset in accordance with IAS 32). [Refer: Credit risk [member]] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Note Effective 2018-01-01 -Name IFRS -Number 7 -IssueDate 2017-01-01 -Paragraph 35K -Subparagraph a -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=7&date=2017-03-01&anchor=para_35K_a&doctype=Standard -URIDate 2017-03-09 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Note Expiry date 2018-01-01 -Name IFRS -Number 7 -IssueDate 2017-01-01 -Paragraph 36 -Subparagraph a -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=7&date=2017-03-02&anchor=para_36_a&doctype=Standard&book=B -URIDate 2017-03-09 + Details
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