XML 130 R160.htm IDEA: XBRL DOCUMENT
v3.20.1

Share Capital - Summary of Share Capital (Parenthetical) (Detail) - shares | Dec. 31, 2019 | Dec. 31, 2018
--- | --- | ---
Disclosure of classes of share capital [abstract] |  |
Treasury shares | 51,787,959 | 51,787,959

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

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