XML 184 R172.htm IDEA: XBRL DOCUMENT
v3.21.1

Accumulated Other Comprehensive Income and Other Components of Equity - Summary of Treasury Stock (Detail) - KRW (₩) ₩ in Millions | Dec. 31, 2020 | Dec. 31, 2019
--- | --- | ---
Miscellaneous equity [abstract] |  |
Number of shares (in shares) | 19,269,678 | 15,870,258
Amounts (In millions of Korean won) | ₩ 882,224 | ₩ 825,838

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

X
- Definition An entity’s own equity instruments, held by the entity or other members of the consolidated group. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Name IAS -Number 1 -IssueDate 2020-01-01 -Paragraph 78 -Subparagraph e -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=1&code=ifrs-tx-2020-en-r&anchor=para_78_e&doctype=Standard -URIDate 2020-01-01 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 32 -IssueDate 2020-01-01 -Paragraph 34 -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=32&code=ifrs-tx-2020-en-r&anchor=para_34&doctype=Standard -URIDate 2020-01-01 + Details
Name: | ifrs-full_TreasuryShares
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Number of treasury shares. + References No definition available. + Details
Name: | kt_NumberOfTreasuryShares
Namespace Prefix: | kt_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | instant