XML 215 R203.htm IDEA: XBRL DOCUMENT
v3.21.1

Related Party Transactions - Summary of Related Parties Outstanding Balances of Receivables and Payables (Detail) - KRW (₩) ₩ in Millions | Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018
--- | --- | --- | ---
Disclosure of transactions between related parties [line items] |  |  |
Dividend Income |  |  | ₩ 11,146
Payables | ₩ 20,857 | ₩ 57,907 |
K-Realty CR-REITs No.1 [member] |  |  |
Disclosure of transactions between related parties [line items] |  |  |
Dividend Income |  |  | 8,932
Others [member] |  |  |
Disclosure of transactions between related parties [line items] |  |  |
Dividend Income |  |  | ₩ 2,148
Trade receivables [member] |  |  |
Disclosure of transactions between related parties [line items] |  |  |
Dividend Income | 1,304 | 1,625 |
Trade receivables [member] | K-Realty CR-REITs No.1 [member] |  |  |
Disclosure of transactions between related parties [line items] |  |  |
Dividend Income | 457 | 608 |
Trade receivables [member] | K Bank Inc. [member] |  |  |
Disclosure of transactions between related parties [line items] |  |  |
Dividend Income | 775 | 583 |
Trade receivables [member] | Others [member] |  |  |
Disclosure of transactions between related parties [line items] |  |  |
Dividend Income | 72 | 434 |
Loans and receivables [member] |  |  |
Disclosure of transactions between related parties [line items] |  |  |
Dividend Income | 50,311 | 37,941 |
Loans and receivables [member] | K-Realty CR-REITs No.1 [member] |  |  |
Disclosure of transactions between related parties [line items] |  |  |
Dividend Income | 16,200 | 23,100 |
Loans and receivables [member] | K Bank Inc. [member] |  |  |
Disclosure of transactions between related parties [line items] |  |  |
Dividend Income | 32,964 | 13,664 |
Loans and receivables [member] | Others [member] |  |  |
Disclosure of transactions between related parties [line items] |  |  |
Dividend Income | 1,147 | 1,177 |
Other payables [member] |  |  |
Disclosure of transactions between related parties [line items] |  |  |
Payables | 1,749 | 1,268 |
Other payables [member] | K-Realty CR-REITs No.1 [member] |  |  |
Disclosure of transactions between related parties [line items] |  |  |
Payables | 20,857 | 57,907 |
Other payables [member] | K Bank Inc. [member] |  |  |
Disclosure of transactions between related parties [line items] |  |  |
Payables | 891 | 557 |
Other payables [member] | Others [member] |  |  |
Disclosure of transactions between related parties [line items] |  |  |
Payables | ₩ 858 | ₩ 711 |

X
- Definition The amounts payable resulting from related party transactions. [Refer: Related parties [member]] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 24 -IssueDate 2020-01-01 -Paragraph 20 -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=24&code=ifrs-tx-2020-en-r&anchor=para_20&doctype=Standard -URIDate 2020-01-01 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 24 -IssueDate 2020-01-01 -Paragraph 18 -Subparagraph b -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=24&code=ifrs-tx-2020-en-r&anchor=para_18_b&doctype=Standard -URIDate 2020-01-01 + Details
Name: | ifrs-full_AmountsPayableRelatedPartyTransactions
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition The amounts receivable resulting from related party transactions. [Refer: Related parties [member]] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 24 -IssueDate 2020-01-01 -Paragraph 20 -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=24&code=ifrs-tx-2020-en-r&anchor=para_20&doctype=Standard -URIDate 2020-01-01 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 24 -IssueDate 2020-01-01 -Paragraph 18 -Subparagraph b -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=24&code=ifrs-tx-2020-en-r&anchor=para_18_b&doctype=Standard -URIDate 2020-01-01 + Details
Name: | ifrs-full_AmountsReceivableRelatedPartyTransactions
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

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

X
- Details
Name: | ifrs-full_CategoriesOfRelatedPartiesAxis=kt_KrealtyCrReitsNoOneMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_CategoriesOfRelatedPartiesAxis=ifrs-full_OtherRelatedPartiesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

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

X
- Details
Name: | ifrs-full_CategoriesOfRelatedPartiesAxis=kt_KBankIncMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

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

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