XML 193 R181.htm IDEA: XBRL DOCUMENT
v3.19.1

Operating Expenses - Summary of Operating Expenses (Detail) - KRW (₩) ₩ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2018 | Dec. 31, 2017 | Dec. 31, 2016
Profit (loss) [abstract] |  |  |
Salaries and wages | ₩ 3,845,842 | ₩ 3,568,456 | ₩ 3,477,596
Depreciation | 2,674,205 | 2,745,969 | 2,762,773
Amortization of intangible assets | 607,527 | 618,533 | 582,493
Commissions | 1,080,168 | 1,085,865 | 1,099,429
Interconnection charges | 579,613 | 640,612 | 690,285
International interconnection fee | 226,627 | 214,058 | 216,633
Purchase of inventories | 4,414,094 | 4,053,693 | 3,407,263
Changes of inventories | (432,607) | (187,439) | 162,323
Sales commission | 1,942,841 | 2,201,778 | 1,968,035
Service cost | 1,540,869 | 1,428,405 | 1,322,337
Utilities | 323,411 | 323,313 | 323,406
Taxes and dues | 285,131 | 279,574 | 255,480
Rent | 460,377 | 448,772 | 455,457
Insurance premium | 73,654 | 69,384 | 178,231
Installation fee | 143,669 | 146,783 | 156,669
Advertising expenses | 157,675 | 197,114 | 185,560
Research and development expenses | 176,758 | 168,635 | 167,881
Card service cost | 3,112,618 | 3,094,894 | 3,049,559
Others | 1,122,718 | 1,379,438 | 1,319,688
Total | ₩ 22,335,190 | ₩ 22,477,837 | ₩ 21,781,098

X
- Definition The amount of amortisation expense. Amortisation is the systematic allocation of depreciable amounts of intangible assets over their useful lives. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Name IAS -Number 1 -IssueDate 2018-01-01 -Paragraph 112 -Subparagraph c -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=1&date=2018-03-01&anchor=para_112_c&doctype=Standard -URIDate 2018-03-16 + Details
Name: | ifrs-full_AmortisationExpense
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition The amount of depreciation expense. Depreciation is the systematic allocation of depreciable amounts of tangible assets over their useful lives. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Name IAS -Number 1 -IssueDate 2018-01-01 -Paragraph 112 -Subparagraph c -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=1&date=2018-03-01&anchor=para_112_c&doctype=Standard -URIDate 2018-03-16 + Details
Name: | ifrs-full_DepreciationExpense
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition The amount of expense relating to fees and commissions. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Name IAS -Number 1 -IssueDate 2018-01-01 -Paragraph 85 -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=1&date=2018-03-01&anchor=para_85&doctype=Standard -URIDate 2018-03-16 + Details
Name: | ifrs-full_FeeAndCommissionExpense
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition The amount of expense arising from purchased insurance. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Name IAS -Number 1 -IssueDate 2018-01-01 -Paragraph 112 -Subparagraph c -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=1&date=2018-03-01&anchor=para_112_c&doctype=Standard -URIDate 2018-03-16 + Details
Name: | ifrs-full_InsuranceExpense
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition The amount of miscellaneous other operating expenses. [Refer: Other operating income (expense)] + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Name IAS -Number 1 -IssueDate 2018-01-01 -Paragraph 112 -Subparagraph c -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=1&date=2018-03-01&anchor=para_112_c&doctype=Standard -URIDate 2018-03-16 + Details
Name: | ifrs-full_MiscellaneousOtherOperatingExpense
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition The amount of all operating expenses. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Name IAS -Number 1 -IssueDate 2018-01-01 -Paragraph 85 -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=1&date=2018-03-01&anchor=para_85&doctype=Standard -URIDate 2018-03-16 + Details
Name: | ifrs-full_OperatingExpense
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- References No definition available. + Details
Name: | ifrs-full_ProfitLossAbstract
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition The amount of expense recognised on rental activities. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Name IAS -Number 1 -IssueDate 2018-01-01 -Paragraph 85 -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=1&date=2018-03-01&anchor=para_85&doctype=Standard -URIDate 2018-03-16 + Details
Name: | ifrs-full_RentalExpense
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition The amount of expenditure directly attributable to research or development activities, recognised in profit or loss. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 38 -IssueDate 2018-01-01 -Paragraph 126 -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=38&date=2018-03-01&anchor=para_126&doctype=Standard -URIDate 2018-03-16 + Details
Name: | ifrs-full_ResearchAndDevelopmentExpense
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition The amount of expense arising from services. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Name IAS -Number 1 -IssueDate 2018-01-01 -Paragraph 85 -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=1&date=2018-03-01&anchor=para_85&doctype=Standard -URIDate 2018-03-16 + Details
Name: | ifrs-full_ServicesExpense
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition The amount of expense arising from purchased utilities. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Name IAS -Number 1 -IssueDate 2018-01-01 -Paragraph 112 -Subparagraph c -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=1&date=2018-03-01&anchor=para_112_c&doctype=Standard -URIDate 2018-03-16 + Details
Name: | ifrs-full_UtilitiesExpense
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition A class of employee benefits expense that represents wages and salaries. [Refer: Employee benefits expense] + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Name IAS -Number 19 -IssueDate 2018-01-01 -Paragraph 9 -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=19&date=2018-03-01&anchor=para_9&doctype=Standard -URIDate 2018-03-16 + Details
Name: | ifrs-full_WagesAndSalaries
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Advertising expense1. + References No definition available. + Details
Name: | kt_AdvertisingExpense1
Namespace Prefix: | kt_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Card service cost. + References No definition available. + Details
Name: | kt_CardServiceCost
Namespace Prefix: | kt_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Changes of inventories. + References No definition available. + Details
Name: | kt_ChangesOfInventories
Namespace Prefix: | kt_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Installation fee. + References No definition available. + Details
Name: | kt_InstallationFee
Namespace Prefix: | kt_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Interconnection charges. + References No definition available. + Details
Name: | kt_InterconnectionCharges
Namespace Prefix: | kt_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition International interconnection fee. + References No definition available. + Details
Name: | kt_InternationalInterconnectionFee
Namespace Prefix: | kt_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Purchase of inventories. + References No definition available. + Details
Name: | kt_PurchaseOfInventories
Namespace Prefix: | kt_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Sales commission. + References No definition available. + Details
Name: | kt_SalesCommission
Namespace Prefix: | kt_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Taxes and dues. + References No definition available. + Details
Name: | kt_TaxesAndDues
Namespace Prefix: | kt_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration