XML 175 R163.htm IDEA: XBRL DOCUMENT v3.21.1

Leases - Additional Information (Detail) - KRW (₩) ₩ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Disclosure Of Arrangement Involving Legal Form Of Lease [Abstract]
Cash outflow for leases	₩ 492,772	₩ 532,730
Increase decrease in right of use assets	₩ 404,293

X

- Definition

The cash outflow for leases.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 16
-IssueDate 2020-01-01
-Paragraph 53
-Subparagraph g
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=16&code=ifrs-tx-2020-en-r&anchor=para_53_g&doctype=Standard
-URIDate 2020-01-01

+ Details

Name:	ifrs-full_CashOutflowForLeases
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

X

- Definition

Disclosure Of arrangement involving legal form of lease.

+ References

No definition available.

+ Details

Name:	kt_DisclosureOfArrangementInvolvingLegalFormOfLeaseAbstract
Namespace Prefix:	kt_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

X

- Definition

Increase Decrease In Right Of Use Assets

+ References

No definition available.

+ Details

Name:	kt_IncreaseDecreaseInRightOfUseAssets
Namespace Prefix:	kt_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration