XML 169 R157.htm IDEA: XBRL DOCUMENT
v3.21.1

Commitments and Contingencies - Summary of Major Commitments with Local Financial Institutions (Detail) - Dec. 31, 2020 $ in Thousands, ₩ in Millions | KRW (₩) | USD ($)
--- | --- | ---
Disclosure of detailed information about borrowings [line items] |  |
Limit | ₩ 2,559,505 | $ 281,054
Used amount | 202,577 | 93,471
Bank overdraft [member] | Kookmin Bank and others [member] |  |
Disclosure of detailed information about borrowings [line items] |  |
Limit | 1,502,000 |
Used amount | 0 |
Inter-Korean Cooperation Fund [member] | Export-Import Bank of Korea [member] |  |
Disclosure of detailed information about borrowings [line items] |  |
Limit | 37,700 |
Used amount | 2,714 |
Insurance for Economic Cooperation project [Member] | Export-Import Bank of Korea [member] |  |
Disclosure of detailed information about borrowings [line items] |  |
Limit | 3,240 |
Used amount | 1,732 |
Collateralised loans on electronic receivable-trade [member] | Shinhan Bank and others [member] |  |
Disclosure of detailed information about borrowings [line items] |  |
Limit | 522,849 |
Used amount | 23,475 |
Plus electronic notes payable [member] | Industrial Bank of Korea [member] |  |
Disclosure of detailed information about borrowings [line items] |  |
Limit | 50,000 |
Used amount | 331 |
Loans for working capital [member] | Korea Development Bank and others [member] |  |
Disclosure of detailed information about borrowings [line items] |  |
Limit | 243,593 |
Used amount | 152,243 |
Facility loans [member] | Kookmin Bank and others [member] |  |
Disclosure of detailed information about borrowings [line items] |  |
Limit | $ |  | 212,000
Used amount | $ |  | 48,855
Facility loans [member] | Shinhan Bank and others [member] |  |
Disclosure of detailed information about borrowings [line items] |  |
Limit | 100,123 |
Used amount | 55 |
Derivatives transaction limit [member] | Korea Development Bank [member] |  |
Disclosure of detailed information about borrowings [line items] |  |
Limit | 100,000 |
Used amount | ₩ 22,027 |
Derivatives transaction limit [member] | Woori Bank and others [Member] |  |
Disclosure of detailed information about borrowings [line items] |  |
Limit | $ |  | 69,054
Used amount | $ |  | $ 44,616

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_DisclosureOfDetailedInformationAboutBorrowingsLineItems
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Line of credit facility maximum amount outstanding. + References No definition available. + Details
Name: | kt_LineOfCreditFacilityMaximumAmountOutstanding
Namespace Prefix: | kt_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Line of credit facility, used amount. + References No definition available. + Details
Name: | kt_LineOfCreditFacilityUsedAmount
Namespace Prefix: | kt_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Details
Name: | ifrs-full_ClassesOfFinancialInstrumentsAxis=kt_BankOverdraftMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_CounterpartiesAxis=kt_KookminBankAndOthersMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_ClassesOfFinancialInstrumentsAxis=kt_InterKoreanCooperationFundMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_CounterpartiesAxis=kt_ExportImportBankOfKoreaMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_ClassesOfFinancialInstrumentsAxis=kt_InsuranceForEconomicCooperationProjectMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_ClassesOfFinancialInstrumentsAxis=kt_CollateralisedLoansOnElectronicReceivableTradeMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_CounterpartiesAxis=kt_ShinhanBankAndOthersMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_ClassesOfFinancialInstrumentsAxis=kt_PlusElectronicNotesPayableMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_CounterpartiesAxis=kt_IndustrialBankOfKoreaMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_ClassesOfFinancialInstrumentsAxis=kt_LoansForWorkingCapitalMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_CounterpartiesAxis=kt_KoreaDevelopmentBankAndOthersMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_ClassesOfFinancialInstrumentsAxis=kt_FacilityLoansMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_ClassesOfFinancialInstrumentsAxis=kt_DerivativesTransactionLimitMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_CounterpartiesAxis=kt_KoreaDevelopmentBankMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_CounterpartiesAxis=kt_wooriBankAndOthersMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |