XML 119 R107.htm IDEA: XBRL DOCUMENT v3.19.1

Other Financial Assets and Liabilities - Additional Information (Detail) - KRW (₩) ₩ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Disclosure of detailed information about financial instruments [line items]
Available-for-sales financial assets at fair value through profit or loss	₩ 94,531
Available-for-sales classified as financial assets at fair value through other comprehensive income	257,819
Ineffective portion recognized in profit or loss cash flow hedge valuation gain	263	₩ 1,961	₩ 1,637
Korea software financial cooperative [member]
Disclosure of detailed information about financial instruments [line items]
Available-for-sale financial assets investment amount	₩ 1,136

X

- Definition

The amount of current financial assets available-for-sale. [Refer: Financial assets available-for-sale; Current financial assets]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Note Expiry date 2021-01-01
-Name IFRS
-Number 7
-IssueDate 2018-01-01
-Paragraph 8
-Subparagraph d
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=7&date=2017-03-02&anchor=para_8_d&doctype=Standard&book=b
-URIDate 2018-03-16

+ Details

Name:	ifrs-full_CurrentFinancialAssetsAvailableforsale
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_DisclosureOfFinancialInstrumentsLineItems
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

X

- Definition

The amount of financial assets that the entity has pledged as collateral for liabilities or contingent liabilities, including amounts that have been reclassified in accordance with paragraph 3.2.23(a) of IFRS 9. [Refer: Contingent liabilities [member]; Financial assets]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 7
-IssueDate 2018-01-01
-Paragraph 14
-Subparagraph a
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=7&date=2018-03-01&anchor=para_14_a&doctype=Standard
-URIDate 2018-03-16

+ Details

Name:	ifrs-full_FinancialAssetsPledgedAsCollateralForLiabilitiesOrContingentLiabilities
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

X

- Definition

The gains (losses) on the ineffective portion of cash flow hedges recognised in profit or loss. [Refer: Cash flow hedges [member]]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Note Expiry date 2021-01-01
-Name IFRS
-Number 7
-IssueDate 2018-01-01
-Paragraph 24
-Subparagraph b
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=7&date=2017-03-02&anchor=para_24_b&doctype=Standard&book=b
-URIDate 2018-03-16

+ Details

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

X

- Definition

Available-for-sales classified as financial assets at fair value through other comprehensive income.

+ References

No definition available.

+ Details

Name:	kt_AvailableforsalesClassifiedAsFinancialAssetsAtFairValueThroughOtherComprehensiveIncome
Namespace Prefix:	kt_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

X

- Details

Name:	ifrs-full_SignificantInvestmentsInAssociatesAxis=kt_KoreaSoftwareFinancialCooperativeMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: