XML 78 R66.htm IDEA: XBRL DOCUMENT
v3.21.1

Net Defined Benefit Liabilities (Tables) | 12 Months Ended
--- | ---
Dec. 31, 2020
Statement [LineItems] |
Summary of Amount Recognized in the Statements of Financial Position and Defined Benefit Obligations | The amounts recognized in the statements of financial position are determined as follows:
(In millions of Korean won) |  | December 31, 2019 |  |  | December 31, 2020 |
Present value of defined benefit obligations |  | ￦ | 2,427,351 |  |  | ￦ | 2,556,712 |
Fair value of plan assets |  |  | (2,069,710 | ) |  |  | (2,189,375 | )
Liabilities |  | ￦ | 365,663 |  |  | ￦ | 378,087 |
Assets in the statement of financial position |  | ￦ | 8,022 |  |  | ￦ | 10,750 |
Summary of Changes in the Defined Benefit Obligations | Changes in the defined benefit obligations for the years ended December 31, 2019 and 2020, are as follows:
(In millions of Korean won) |  | 2019 |  |  | 2020 |
Beginning |  | ￦ | 2,201,876 |  |  | ￦ | 2,427,351 |
Current service cost |  |  | 243,598 |  |  |  | 248,047 |
Interest expense |  |  | 47,403 |  |  |  | 45,083 |
Benefit paid |  |  | (100,663 | ) |  |  | (258,866 | )
Changes due to settlements of plan |  |  | 910 |  |  |  | 1,075 |
Remeasurements: |  |  |  |  |  |  |  |
Actuarial gains and losses arising from changes in demographic assumptions |  |  | 39 |  |  |  | 5,191 |
Actuarial gains and losses arising from changes in financial assumptions |  |  | 11,773 |  |  |  | 17,077 |
Actuarial gains and losses arising from experience adjustments |  |  | 19,465 |  |  |  | 57,703 |
Changes in scope of consolidation |  |  | 2,950 |  |  |  | 14,051 |
Ending |  | ￦ | 2,427,351 |  |  | ￦ | 2,556,712 |
Changes in the fair value of plan assets for the years ended December 31, 2019 and 2020, are as follows:
(In millions of Korean won) |  | 2019 |  |  | 2020 |
Beginning |  | ￦ | 1,643,046 |  |  | ￦ | 2,069,710 |
Interest income |  |  | 35,386 |  |  |  | 38,590 |
Remeasurements: |  |  |  |  |  |  |  |
Return on plan assets (excluding amounts included in interest income) |  |  | (2,537 | ) |  |  | 2,589 |
Benefits paid |  |  | (87,119 | ) |  |  | (213,953 | )
Employer contributions |  |  | 476,916 |  |  |  | 284,243 |
Changes in scope of consolidation |  |  | 4,018 |  |  |  | 8,196 |
Ending |  | ￦ | 2,069,710 |  |  | ￦ | 2,189,375 |
Summary of Amounts Recognized in the Operating expenses of the Consolidated Statements of Operations | Amounts recognized in the ‘Operating expenses’ of the consolidated statements of operations for the years ended December 31, 2018, 2019 and 2020, are as follows:
(In millions of Korean won) |  | 2018 |  |  | 2019 |  |  | 2020 |
Current service cost |  | ￦ | 225,667 |  |  | ￦ | 243,598 |  |  | ￦ | 248,047 |
Net Interest cost |  |  | 10,458 |  |  |  | 12,017 |  |  |  | 6,494 |
Past service cost |  |  | 9,801 |  |  |  | 910 |  |  |  | 1,075 |
Transfer out |  |  | (13,881 | ) |  |  | (16,215 | ) |  |  | (16,514 | )
Total expenses |  | ￦ | 232,045 |  |  | ￦ | 240,310 |  |  | ￦ | 239,102 |
Summary of Principal Actuarial Assumptions | Principal actuarial assumptions used are as follows:
|  | December 31, 2018 |  |  | December 31, 2019 |  |  | December 31, 2020 |
Discount rate |  |  | 2.32 | % |  |  | 1.97 | % |  |  | 1.93 | %
Future salary increase |  |  | 5.08 | % |  |  | 4.92 | % |  |  | 4.88 | %
Summary of Expected Maturity Analysis of Undiscounted Pension Benefits | The expected maturity analysis of undiscounted pension benefits as at December 31, 2020, is as follows:
(In millions of Korean won) |  | Less than 1 year |  |  | Between 1-2 years |  |  | Between 2-5 years |  |  | Over 5 years |  |  | Total |
Pension benefits |  | ￦ | 232,550 |  |  | ￦ | 271,366 |  |  | ￦ | 794,840 |  |  | ￦ | 2,284,517 |  |  | ￦ | 3,583,273 |
Defined benefit obligations [member] |
Statement [LineItems] |
Summary of Sensitivity of the Defined Benefit Obligations | The sensitivity of the defined benefit obligations as at December 31, 2020, to changes in the principal assumptions is:
(In percentage, in millions of Korean won) |  | Effect on defined benefit obligation |
|  | Changes in assumption |  | Increase in assumption |  |  | Decrease in assumption |
Discount rate |  | 0.5% point |  |  | ￦ (86,288) |  |  | ￦ | 93,254 |
Salary growth rate |  | 0.5% point |  |  | 85,344 |  |  |  | (79,970 | )

X
- Definition The disclosure of additional information about defined benefit plans necessary to meet the objectives of IAS 19. [Refer: Defined benefit plans [member]] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 19 -IssueDate 2020-01-01 -Paragraph 137 -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=19&code=ifrs-tx-2020-en-r&anchor=para_137&doctype=Standard -URIDate 2020-01-01 + Details
Name: | ifrs-full_DisclosureOfAdditionalInformationAboutDefinedBenefitPlansExplanatory
Namespace Prefix: | ifrs-full_
Data Type: | nonnum:textBlockItemType
Balance Type: | na
Period Type: | duration

X
- Definition The disclosure of a net defined benefit liability (asset). [Refer: Net defined benefit liability (asset)] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 19 -IssueDate 2020-01-01 -Paragraph 140 -Subparagraph a -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=19&code=ifrs-tx-2020-en-r&anchor=para_140_a&doctype=Standard -URIDate 2020-01-01 + Details
Name: | ifrs-full_DisclosureOfNetDefinedBenefitLiabilityAssetExplanatory
Namespace Prefix: | ifrs-full_
Data Type: | nonnum:textBlockItemType
Balance Type: | na
Period Type: | duration

X
- Definition The disclosure of a sensitivity analysis for significant actuarial assumptions used to determine the present value of a defined benefit obligation. [Refer: Actuarial assumptions [member]; Defined benefit obligation, at present value] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 19 -IssueDate 2020-01-01 -Paragraph 145 -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=19&code=ifrs-tx-2020-en-r&anchor=para_145&doctype=Standard -URIDate 2020-01-01 + Details
Name: | ifrs-full_DisclosureOfSensitivityAnalysisForActuarialAssumptionsExplanatory
Namespace Prefix: | ifrs-full_
Data Type: | nonnum:textBlockItemType
Balance Type: | na
Period Type: | duration

X
- Definition Disclosure of actuarial assumption of discount rates explanatory. + References No definition available. + Details
Name: | kt_DisclosureOfActuarialAssumptionOfDiscountRatesExplanatoryTextBlock
Namespace Prefix: | kt_
Data Type: | nonnum:textBlockItemType
Balance Type: | na
Period Type: | duration

X
- Definition The disclosure of changes in defined benefit obligations. + References No definition available. + Details
Name: | kt_DisclosureOfChangesInDefinedBenefitObligationsExplanatory
Namespace Prefix: | kt_
Data Type: | nonnum:textBlockItemType
Balance Type: | na
Period Type: | duration

X
- Definition The disclosure of expected maturity analysis of undiscounted pension benefits. + References No definition available. + Details
Name: | kt_DisclosureOfExpectedMaturityAnalysisOfUndiscountedPensionBenefitsExplanatory
Namespace Prefix: | kt_
Data Type: | nonnum:textBlockItemType
Balance Type: | na
Period Type: | duration

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

X
- Details
Name: | ifrs-full_NetDefinedBenefitLiabilityAssetAxis=kt_DefinedBenefitObligationsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |