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Fair Value - Summary of Carrying Amount and Fair Value of Financial Instruments by Category (Detail) - KRW (₩) ₩ in Millions | Dec. 31, 2017 | Dec. 31, 2016
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Disclosure of detailed information about financial instruments [Line Items] |  |
Financial assets | ₩ 10,237,369 | ₩ 10,216,182
Financial liabilities | 15,295,656 | 16,557,537
Trade and other payables [Member] |  |
Disclosure of detailed information about financial instruments [Line Items] |  |
Financial liabilities | 8,425,503 | 8,328,082
Borrowings [Member] |  |
Disclosure of detailed information about financial instruments [Line Items] |  |
Financial liabilities | 6,683,662 | 8,120,791
Financial liabilities designated as at fair value through profit or loss [member] |  |
Disclosure of detailed information about financial instruments [Line Items] |  |
Financial liabilities | 5,051 | 1,973
Derivative financial instruments for hedging purpose [Member] |  |
Disclosure of detailed information about financial instruments [Line Items] |  |
Financial liabilities | 93,770 | 14,928
Other [Member] |  |
Disclosure of detailed information about financial instruments [Line Items] |  |
Financial liabilities | 87,670 | 91,763
Cash and cash equivalents [Member] |  |
Disclosure of detailed information about financial instruments [Line Items] |  |
Financial assets | 1,928,182 | 2,900,311
Trade and other receivables [Member] |  |
Disclosure of detailed information about financial instruments [Line Items] |  |
Financial assets | 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] |  |
Financial assets | 5,813 | 6,277
Derivative financial instruments for hedging purpose [Member] |  |
Disclosure of detailed information about financial instruments [Line Items] |  |
Financial assets | 7,389 | 227,318
Time deposits and others [Member] |  |
Disclosure of detailed information about financial instruments [Line Items] |  |
Financial assets | 1,333,317 | 716,769
Held-to-maturity financial assets [member] |  |
Disclosure of detailed information about financial instruments [Line Items] |  |
Financial assets | 151 | 30,143
Available-for-sale [member] |  |
Disclosure of detailed information about financial instruments [Line Items] |  |
Financial assets | 319,402 | 299,001
Fair value [Member] | | Borrowings [Member] |  |
Disclosure of detailed information about financial instruments [Line Items] |  |
Financial liabilities | 6,738,326 | 8,184,195
Fair value [Member] | | Financial liabilities designated as at fair value through profit or loss [member] |  |
Disclosure of detailed information about financial instruments [Line Items] |  |
Financial liabilities | 5,051 | 1,973
Fair value [Member] | | Derivative financial instruments for hedging purpose [Member] |  |
Disclosure of detailed information about financial instruments [Line Items] |  |
Financial liabilities | 93,770 | 14,928
Fair value [Member] | | Financial assets at fair value through profit or loss [member] |  |
Disclosure of detailed information about financial instruments [Line Items] |  |
Financial assets | 5,813 | 6,277
Fair value [Member] | | Derivative financial instruments for hedging purpose [Member] |  |
Disclosure of detailed information about financial instruments [Line Items] |  |
Financial assets | 7,389 | 227,318
Fair value [Member] | | Held-to-maturity financial assets [member] |  |
Disclosure of detailed information about financial instruments [Line Items] |  |
Financial assets | 151 | 30,143
Fair value [Member] | | Available-for-sale [member] |  |
Disclosure of detailed information about financial instruments [Line Items] |  |
Financial assets | ₩ 319,402 | ₩ 299,001

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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 of assets that are: (a) cash; (b) an equity instrument of another entity; (c) a contractual right: (i) to receive cash or another financial asset from another entity; or (ii) to exchange financial assets or financial liabilities with another entity under conditions that are potentially favourable to the entity; or (d) a contract that will, or may be, settled in the entity’s own equity instruments and is: (i) a non-derivative for which the entity is, or may be, obliged to receive a variable number of the entity’s own equity instruments; or (ii) a derivative that will, or may be, settled other than by the exchange of a fixed amount of cash or another financial asset for a fixed number of the entity’s own equity instruments. For this purpose the entity’s own equity instruments do not include puttable financial instruments classified as equity instruments in accordance with paragraphs 16A-16B of IAS 32, instruments that impose on the entity an obligation to deliver to another party a pro rata share of the net assets of the entity only on liquidation and are classified as equity instruments in accordance with paragraphs 16C-16D of IAS 32, or instruments that are contracts for the future receipt or delivery of the entity’s own equity instruments. [Refer: Financial instruments, class [member]; Financial liabilities] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 7 -IssueDate 2017-01-01 -Paragraph 25 -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=7&date=2017-03-01&anchor=para_25&doctype=Standard -URIDate 2017-03-09 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Note Effective 2018-01-01 -Name IFRS -Number 7 -IssueDate 2017-01-01 -Paragraph 35H -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=7&date=2017-03-01&anchor=para_35H&doctype=Standard -URIDate 2017-03-09 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Note Effective 2018-01-01 -Name IFRS -Number 7 -IssueDate 2017-01-01 -Paragraph 35I -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=7&date=2017-03-01&anchor=para_35I&doctype=Standard -URIDate 2017-03-09 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Note Effective 2018-01-01 -Name IFRS -Number 7 -IssueDate 2017-01-01 -Paragraph 35M -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=7&date=2017-03-01&anchor=para_35M&doctype=Standard -URIDate 2017-03-09 Reference 5: http://www.xbrl.org/2003/role/exampleRef -Note Effective 2018-01-01 -Name IFRS -Number 7 -IssueDate 2017-01-01 -Paragraph 35N -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=7&date=2017-03-01&anchor=para_35N&doctype=Standard -URIDate 2017-03-09 + Details
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- Definition The amount of liabilities that are: (a) a contractual obligation: (i) to deliver cash or another financial asset to another entity; or (ii) to exchange financial assets or financial liabilities with another entity under conditions that are potentially unfavourable to the entity; or (b) a contract that will, or may be, settled in the entity’s own equity instruments and is: (i) a non-derivative for which the entity is, or may be, obliged to deliver a variable number of the entity’s own equity instruments; or (ii) a derivative that will, or may be, settled other than by the exchange of a fixed amount of cash or another financial asset for a fixed number of the entity’s own equity instruments. For this purpose, rights, options or warrants to acquire a fixed number of the entity’s own equity instruments for a fixed amount of any currency are equity instruments if the entity offers the rights, options or warrants pro rata to all of its existing owners of the same class of its own non-derivative equity instruments. Also, for those purposes the entity’s own equity instruments do not include puttable financial instruments that are classified as equity instruments in accordance with paragraphs 16A-16B of IAS 32, instruments that impose on the entity an obligation to deliver to another party a pro rata share of the net assets of the entity only on liquidation and are classified as equity instruments in accordance with paragraphs 16C-16D of IAS 32, or instruments that are contracts for the future receipt or delivery of the entity’s own equity instruments. As an exception, an instrument that meets the definition of a financial liability is classified as an equity instrument if it has all the features and meets the conditions in paragraphs 16A-16B or paragraphs 16C-16D of IAS 32. [Refer: Financial instruments, class [member]; Financial assets; Derivatives [member]] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 7 -IssueDate 2017-01-01 -Paragraph 25 -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=7&date=2017-03-01&anchor=para_25&doctype=Standard -URIDate 2017-03-09 + Details
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