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Accumulated Other Comprehensive Income and Other Components of Equity - Summary of Changes in Accumulated Other Comprehensive Income (Detail) - KRW (₩) ₩ in Millions | 12 Months Ended
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Dec. 31, 2017 | Dec. 31, 2016
Beginning | ₩ (1,432) | ₩ 13,870
Increase /decrease | (54,062) | 64,082
Reclassified to gain or loss | 86,479 | (79,384)
Ending | 30,985 | (1,432)
Changes in investments in associates and joint ventures [member] |  |
Beginning | (10,883) | (10,312)
Increase /decrease | 10,148 | (571)
Ending | (735) | (10,883)
Loss on derivatives valuation [member] |  |
Beginning | (34,309) | (23,234)
Increase /decrease | (111,083) | 64,796
Reclassified to gain or loss | 141,929 | (75,871)
Ending | (3,463) | (34,309)
Gain of valuation on available for sale [member] |  |
Beginning | 54,106 | 52,415
Increase /decrease | 54,017 | 5,204
Reclassified to gain or loss | (55,450) | (3,513)
Ending | 52,673 | 54,106
Foreign currency translation adjustment [Member] |  |
Beginning | (10,346) | (4,999)
Increase /decrease | (7,144) | (5,347)
Ending | ₩ (17,490) | ₩ (10,346)

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- Definition The amount of accumulated items of income and expense (including reclassification adjustments) that are not recognised in profit or loss as required or permitted by other IFRSs. [Refer: IFRSs [member]; Other comprehensive income] + 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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- Definition The amount of other comprehensive income that will be reclassified to profit or loss, before tax. [Refer: Other comprehensive income] + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Name IAS -Number 1 -IssueDate 2017-01-01 -Paragraph IG6 -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=1&date=2017-03-01&anchor=para_IG6&doctype=Implementation%20Guidance -URIDate 2017-03-09 Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Name IAS -Number 1 -IssueDate 2017-01-01 -Paragraph 82A -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=1&date=2017-03-01&anchor=para_82A&doctype=Standard -URIDate 2017-03-09 + Details
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- Definition Increase (decrease) in other comprehensive income + References No definition available. + Details
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- Details
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- Details
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- Details
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- Details
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