XML 226 R214.htm IDEA: XBRL DOCUMENT
v3.19.1

Fair Value - Summary of Fair Value Non of Financial Instruments (Detail) ₩ in Millions | Dec. 31, 2018 KRW (₩)
--- | ---
Disclosure of detailed information about financial instruments [line items] |
Non financial assets | ₩ 4,052,094
Non financial liabilities | 65,066
Level 1 [Member] |
Disclosure of detailed information about financial instruments [line items] |
Non financial assets | 8,982
Level 2 [Member] |
Disclosure of detailed information about financial instruments [line items] |
Non financial assets | 1,746,915
Non financial liabilities | 47,125
Level 3 [Member] |
Disclosure of detailed information about financial instruments [line items] |
Non financial assets | 2,296,197
Non financial liabilities | 17,941
Financial assets at fair value through other comprehensive income [member] |
Disclosure of detailed information about financial instruments [line items] |
Non financial assets | 1,097,348
Financial assets at fair value through other comprehensive income [member] | Level 2 [Member] |
Disclosure of detailed information about financial instruments [line items] |
Non financial assets | 1,097,348
Financial assets at fair value through profit or loss [member] |
Disclosure of detailed information about financial instruments [line items] |
Non financial assets | 777,685
Financial assets at fair value through profit or loss [member] | Level 1 [Member] |
Disclosure of detailed information about financial instruments [line items] |
Non financial assets | 121
Financial assets at fair value through profit or loss [member] | Level 2 [Member] |
Disclosure of detailed information about financial instruments [line items] |
Non financial assets | 613,964
Financial assets at fair value through profit or loss [member] | Level 3 [Member] |
Disclosure of detailed information about financial instruments [line items] |
Non financial assets | 163,600
Other financial assets at fair value through other comprehensive income [member] |
Disclosure of detailed information about financial instruments [line items] |
Non financial assets | 326,157
Other financial assets at fair value through other comprehensive income [member] | Level 1 [Member] |
Disclosure of detailed information about financial instruments [line items] |
Non financial assets | 8,861
Other financial assets at fair value through other comprehensive income [member] | Level 2 [Member] |
Disclosure of detailed information about financial instruments [line items] |
Non financial assets | 5,760
Other financial assets at fair value through other comprehensive income [member] | Level 3 [Member] |
Disclosure of detailed information about financial instruments [line items] |
Non financial assets | 311,536
Derivative financial assets for hedging [member] |
Disclosure of detailed information about financial instruments [line items] |
Non financial assets | 29,843
Derivative financial assets for hedging [member] | Level 2 [Member] |
Disclosure of detailed information about financial instruments [line items] |
Non financial assets | 29,843
Investment Properties [member] |
Disclosure of detailed information about financial instruments [line items] |
Non financial assets | 1,821,061
Investment Properties [member] | Level 3 [Member] |
Disclosure of detailed information about financial instruments [line items] |
Non financial assets | 1,821,061
Other financial liabilities at fair value through profit or loss [member] |
Disclosure of detailed information about financial instruments [line items] |
Non financial liabilities | 7,758
Other financial liabilities at fair value through profit or loss [member] | Level 3 [Member] |
Disclosure of detailed information about financial instruments [line items] |
Non financial liabilities | 7,758
Derivative financial liabilities for hedging [member] |
Disclosure of detailed information about financial instruments [line items] |
Non financial liabilities | 57,308
Derivative financial liabilities for hedging [member] | Level 2 [Member] |
Disclosure of detailed information about financial instruments [line items] |
Non financial liabilities | 47,125
Derivative financial liabilities for hedging [member] | Level 3 [Member] |
Disclosure of detailed information about financial instruments [line items] |
Non financial liabilities | ₩ 10,183

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 Non financial assets. + References No definition available. + Details
Name: | kt_NonFinancialAssets
Namespace Prefix: | kt_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Non Financial Liabilities + References No definition available. + Details
Name: | kt_NonFinancialLiabilities
Namespace Prefix: | kt_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Details
Name: | ifrs-full_LevelsOfFairValueHierarchyAxis=ifrs-full_Level1OfFairValueHierarchyMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_LevelsOfFairValueHierarchyAxis=ifrs-full_Level2OfFairValueHierarchyMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_LevelsOfFairValueHierarchyAxis=ifrs-full_Level3OfFairValueHierarchyMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

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

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

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

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

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

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

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