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Intangible Assets - Additional Information (Detail) - KRW (₩) ₩ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2017 | Dec. 31, 2016 | Dec. 31, 2015
Disclosure of detailed information about intangible assets [line items] |  |  |
Indefinite useful life | ₩ 238,053 | ₩ 268,350 |
Impairment losses recognized on indefinite-lived intangible assets | 116,095 | ₩ 135,264 | ₩ 292,345
Satellite TV [member] |  |  |
Disclosure of detailed information about intangible assets [line items] |  |  |
Impairment losses recognized on goodwill | 78,200 |  |
Impairment losses recognized on indefinite-lived intangible assets | ₩ 29,325 |  |
Expected growth rate | 0.00% |  |
Estimated revenue growth rate | (0.77%) |  |
Discount rate | 13.25% |  |

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- Definition The discount rate applied to cash flow projections for a cash-generating unit (group of units). [Refer: Cash-generating units [member]] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 36 -IssueDate 2017-01-01 -Paragraph 134 -Subparagraph d -Clause v -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=36&date=2017-03-01&anchor=para_134_d_v&doctype=Standard -URIDate 2017-03-09 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 36 -IssueDate 2017-01-01 -Paragraph 134 -Subparagraph e -Clause v -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=36&date=2017-03-01&anchor=para_134_e_v&doctype=Standard -URIDate 2017-03-09 + Details
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- Definition The growth rate used to extrapolate cash flow projections beyond the period covered by the most recent budgets/forecasts for a cash-generating unit (group of units). [Refer: Cash-generating units [member]] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 36 -IssueDate 2017-01-01 -Paragraph 134 -Subparagraph d -Clause iv -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=36&date=2017-03-01&anchor=para_134_d_iv&doctype=Standard -URIDate 2017-03-09 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 36 -IssueDate 2017-01-01 -Paragraph 134 -Subparagraph e -Clause iv -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=36&date=2017-03-01&anchor=para_134_e_iv&doctype=Standard -URIDate 2017-03-09 + Details
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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 impairment loss recognised in profit or loss for goodwill. [Refer: Impairment loss recognised in profit or loss; Goodwill] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 3 -IssueDate 2017-01-01 -Paragraph B67 -Subparagraph d -Clause v -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=3&date=2017-03-01&anchor=para_B67_d_v&doctype=Appendix&seq=2 -URIDate 2017-03-09 + Details
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- Definition The amount of impairment loss recognised in profit or loss for intangible assets other than goodwill. [Refer: Impairment loss recognised in profit or loss; Intangible assets other than goodwill] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 38 -IssueDate 2017-01-01 -Paragraph 118 -Subparagraph e -Clause iv -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=38&date=2017-03-01&anchor=para_118_e_iv&doctype=Standard -URIDate 2017-03-09 + Details
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