XML 148 R101.htm IDEA: XBRL DOCUMENT
v3.20.1

Other Financial Assets and Liabilities - Additional Information (Detail) - KRW (₩) ₩ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017
Disclosure of detailed information about financial instruments [line items] |  |  |
Ineffective portion recognized in profit or loss cash flow hedge valuation gain | ₩ 4,181 | ₩ 263 | ₩ 1,961
Korea software financial cooperative [member] |  |  |
Disclosure of detailed information about financial instruments [line items] |  |  |
Available-for-sale financial assets investment amount | ₩ 1,849 |  |

X
- 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
Name: | ifrs-full_DisclosureOfFinancialInstrumentsLineItems
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition The amount of financial assets that the entity has pledged as collateral for liabilities or contingent liabilities, including amounts that have been reclassified in accordance with paragraph 3.2.23(a) of IFRS 9. [Refer: Contingent liabilities [member]; Financial assets] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 7 -IssueDate 2019-01-01 -Paragraph 14 -Subparagraph a -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=7&code=ifrs-tx-2019-en-r&anchor=para_14_a&doctype=Standard -URIDate 2019-03-27 + Details
Name: | ifrs-full_FinancialAssetsPledgedAsCollateralForLiabilitiesOrContingentLiabilities
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition The gains (losses) on the ineffective portion of cash flow hedges recognised in profit or loss. [Refer: Cash flow hedges [member]] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Note Expiry date 2021-01-01 -Name IFRS -Number 7 -IssueDate 2019-01-01 -Paragraph 24 -Subparagraph b -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=7&code=ifrs-tx-2017-en-b&anchor=para_24_b&doctype=Standard&book=b -URIDate 2019-03-27 + Details
Name: | ifrs-full_GainsLossesOnIneffectivenessOfCashFlowHedgesRecognisedInProfitOrLoss
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Details
Name: | ifrs-full_SignificantInvestmentsInAssociatesAxis=kt_KoreaSoftwareFinancialCooperativeMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |