XML 179 R167.htm IDEA: XBRL DOCUMENT v3.21.1

Retained Earnings - Summary of Retained Earnings (Parenthetical) (Detail)	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Miscellaneous equity [abstract]
Minimum percentage of cash dividend declared appropriation to legal reserve	10.00%	10.00%
Percentage of legal reserve equal to capital stock issued	50.00%	50.00%

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

Minimum percentage of cash dividend declared appropriation to legal reserve.

+ References

No definition available.

+ Details

Name:	kt_MinimumPercentageOfCashDividendDeclaredAppropriationToLegalReserve
Namespace Prefix:	kt_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

X

- Definition

Percentage of legal reserves equal to capital stock.

+ References

No definition available.

+ Details

Name:	kt_PercentageOfLegalReservesEqualToCapitalStock
Namespace Prefix:	kt_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration