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Borrowings - Summary of Carrying Amount and Fair Value of Debentures and Borrowings (Detail) - KRW (₩) ₩ in Millions | Dec. 31, 2017 | Dec. 31, 2016
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Disclosure of detailed information about borrowings [Line Items] |  |
Long-term borrowings (Including current portion of long-term borrowings) | ₩ 6,683,662 | ₩ 8,120,791
Short-term borrowings | 128,300 | 153,100
Gross carrying amount [member] |  |
Disclosure of detailed information about borrowings [Line Items] |  |
Debentures | 5,968,229 | 7,323,448
Long-term borrowings (Including current portion of long-term borrowings) | 587,133 | 644,243
Short-term borrowings | 128,300 | 153,100
Total | 6,683,662 | 8,120,791
Fair Value [member] |  |
Disclosure of detailed information about borrowings [Line Items] |  |
Debentures | 6,022,551 | 7,387,085
Long-term borrowings (Including current portion of long-term borrowings) | 587,475 | 644,010
Short-term borrowings | 128,300 | 153,100
Total | ₩ 6,738,326 | ₩ 8,184,195

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- Definition The amount of notes and debentures issued by the entity. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Name IAS -Number 1 -IssueDate 2017-01-01 -Paragraph 112 -Subparagraph c -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=1&date=2017-03-01&anchor=para_112_c&doctype=Standard -URIDate 2017-03-09 + Details
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- Definition The amount of current borrowings. [Refer: Borrowings] + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Name IAS -Number 1 -IssueDate 2017-01-01 -Paragraph 55 -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=1&date=2017-03-01&anchor=para_55&doctype=Standard -URIDate 2017-03-09 + Details
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