XML 113 R101.htm IDEA: XBRL DOCUMENT v3.19.1

Trade and Other Receivables - Summary of Changes in Allowance for Doubtful Accounts (Detail) - KRW (₩) ₩ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Trade receivables [member]
Disclosure of financial assets [line items]
Beginning balance	₩ 439,427	₩ 470,871	₩ 468,741
Provision	91,282	38,888	84,975
Reversal or written-off	(170,597)	(70,121)	(80,518)
Changes in the scope of consolidation		(107)	215
Others	(188)	(104)	(2,542)
Ending balance	359,924	439,427	470,871
Other receivables [member]
Disclosure of financial assets [line items]
Beginning balance	84,372	141,616	250,842
Provision	21,783	5,809	7,736
Reversal or written-off	(14,520)	(61,220)	(108,638)
Changes in the scope of consolidation		(35)	56
Others	2,187	(1,798)	(8,380)
Ending balance	₩ 93,822	₩ 84,372	₩ 141,616

X

- Definition

The amount of additional allowance for credit losses of financial assets recognised in profit or loss. [Refer: Allowance account for credit losses of financial assets]

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Note Expiry date 2021-01-01
-Name IFRS
-Number 7
-IssueDate 2018-01-01
-Paragraph 16
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=7&date=2017-03-02&anchor=para_16&doctype=Standard&book=b
-URIDate 2018-03-16

+ Details

Name:	ifrs-full_AdditionalAllowanceRecognisedInProfitOrLossAllowanceAccountForCreditLossesOfFinancialAssets
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:monetaryItemType
Balance Type:	na
Period Type:	duration

X

- Definition

The amount of an allowance account used to record impairments to financial assets due to credit losses. [Refer: 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 16
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=7&date=2017-03-02&anchor=para_16&doctype=Standard&book=b
-URIDate 2018-03-16

+ Details

Name:	ifrs-full_AllowanceAccountForCreditLossesOfFinancialAssets
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
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_DisclosureOfFinancialAssetsLineItems
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

X

- Definition

The increase (decrease) in allowance account for credit losses of financial assets resulting from changes that the entity does not separately disclose in the same statement or note. [Refer: Allowance account for credit losses of financial assets]

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Note Expiry date 2021-01-01
-Name IFRS
-Number 7
-IssueDate 2018-01-01
-Paragraph 16
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=7&date=2017-03-02&anchor=para_16&doctype=Standard&book=b
-URIDate 2018-03-16

+ Details

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

X

- Definition

Allowance for doubtful accounts changes in the scope of consolidation.

+ References

No definition available.

+ Details

Name:	kt_AllowanceForDoubtfulAccountsChangesInTheScopeOfConsolidation
Namespace Prefix:	kt_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

X

- Definition

Reversal or write off allowance account for credit losses of financial assets.

+ References

No definition available.

+ Details

Name:	kt_ReversalOrWriteOffAllowanceAccountForCreditLossesOfFinancialAssets
Namespace Prefix:	kt_
Data Type:	xbrli:monetaryItemType
Balance Type:	na
Period Type:	duration

X

- Details

Name:	ifrs-full_ClassesOfFinancialAssetsAxis=ifrs-full_TradeReceivablesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	ifrs-full_ClassesOfFinancialAssetsAxis=kt_OtherReceivablesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: