XML 248 R236.htm IDEA: XBRL DOCUMENT
v3.19.1

Revision of Prior Financial Statements - Summary of Consolidated Statements of Financial Position (Detail) - KRW (₩) ₩ in Millions | Dec. 31, 2018 | Jan. 01, 2018 | Dec. 31, 2017 | Jan. 01, 2017 | Dec. 31, 2016 | Jan. 01, 2016 | Dec. 31, 2015
--- | --- | --- | --- | --- | --- | --- | ---
Disclosure of changes in accounting policies, accounting estimates and errors [line items] |  |  |  |  |  |  |
Current assets | ₩ 12,157,814 | ₩ 11,117,433 | ₩ 9,828,525 | ₩ 9,866,302 |  |  |
Trade and other receivables | 5,680,349 | 5,969,040 | 5,964,565 | 5,477,634 |  |  |
Total assets | 32,474,120 | 31,252,689 | 29,895,721 | 30,814,580 |  |  |
Current liabilities | 9,394,123 | 9,744,055 | 9,474,162 | 9,539,195 |  |  |
Trade and other payables | 7,007,515 | 7,426,385 | 7,426,088 | 7,141,725 |  |  |
Current income tax liabilities | 249,837 |  | 82,984 | 102,843 |  |  |
Total liabilities | 17,815,630 | 17,062,496 | 16,712,367 | 17,897,638 |  |  |
Equity attribute to owners of the Controlling Company | 13,129,901 | 12,721,456 | 11,791,590 | 11,564,098 | ₩ 11,564,098 | ₩ 10,933,231 |
Retained earnings | 11,256,069 |  | 9,961,150 | 9,778,707 | 9,778,707 | 9,147,467 |
Total equity | 14,658,490 | 14,190,193 | 13,183,354 | 12,916,942 | 12,916,942 |  | ₩ 12,253,627
Total liabilities and equity | 32,474,120 |  | 29,895,721 | 30,814,580 |  |  |
As previously reported [member] |  |  |  |  |  |  |
Disclosure of changes in accounting policies, accounting estimates and errors [line items] |  |  |  |  |  |  |
Current assets | 10,822,686 | 9,828,525 | 9,678,243 | 9,716,020 |  |  |
Trade and other receivables | 5,687,490 | 5,964,565 | 5,814,283 | 5,327,352 |  |  |
Total assets | 31,051,560 | 29,895,721 | 29,745,439 | 30,664,298 |  |  |
Current liabilities | 9,075,863 | 9,474,162 | 9,458,104 | 9,523,137 |  |  |
Trade and other payables |  | 7,426,088 | 7,424,134 | 7,139,771 |  |  |
Current income tax liabilities |  |  | 68,880 | 88,739 |  |  |
Total liabilities | 17,442,862 | 16,712,367 | 16,696,309 | 17,881,580 |  |  |
Equity attribute to owners of the Controlling Company | 12,159,471 | 11,791,590 | 11,657,366 | 11,429,874 | 11,429,874 | 10,835,735 |
Retained earnings |  |  | 9,826,926 | 9,644,483 | 9,644,483 | 9,049,971 |
Total equity | 13,608,698 | ₩ 13,183,354 | 13,049,130 | 12,782,718 |  |  | ₩ 12,156,131
Total liabilities and equity |  |  | 29,745,439 | 30,664,298 |  |  |
Adjustments [member] |  |  |  |  |  |  |
Disclosure of changes in accounting policies, accounting estimates and errors [line items] |  |  |  |  |  |  |
Current assets |  |  | 150,282 | 150,282 |  |  |
Trade and other receivables |  |  | 150,282 | 150,282 |  |  |
Total assets |  |  | 150,282 | 150,282 |  |  |
Current liabilities |  |  | 16,058 | 16,058 |  |  |
Trade and other payables |  |  | 1,954 | 1,954 |  |  |
Current income tax liabilities |  |  | 14,104 | 14,104 |  |  |
Total liabilities |  |  | 16,058 | 16,058 |  |  |
Equity attribute to owners of the Controlling Company |  |  | 134,224 | 134,224 | 134,224 | 97,496 |
Retained earnings | ₩ 97,496 |  | 134,224 | 134,224 | ₩ 134,224 | ₩ 97,496 |
Total equity |  |  | 134,224 | 134,224 |  |  |
Total liabilities and equity |  |  | ₩ 150,282 | ₩ 150,282 |  |  |

X
- Definition The amount of resources: (a) controlled by the entity as a result of past events; and (b) from which future economic benefits are expected to flow to the entity. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 8 -IssueDate 2018-01-01 -Paragraph 28 -Subparagraph c -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=8&date=2018-03-01&anchor=para_28_c&doctype=Standard -URIDate 2018-03-16 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 13 -IssueDate 2018-01-01 -Paragraph 93 -Subparagraph a -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=13&date=2018-03-01&anchor=para_93_a&doctype=Standard -URIDate 2018-03-16 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 13 -IssueDate 2018-01-01 -Paragraph 93 -Subparagraph b -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=13&date=2018-03-01&anchor=para_93_b&doctype=Standard -URIDate 2018-03-16 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 13 -IssueDate 2018-01-01 -Paragraph 93 -Subparagraph e -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=13&date=2018-03-01&anchor=para_93_e&doctype=Standard -URIDate 2018-03-16 Reference 5: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 1 -IssueDate 2018-01-01 -Paragraph 55 -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=1&date=2018-03-01&anchor=para_55&doctype=Standard -URIDate 2018-03-16 Reference 6: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 8 -IssueDate 2018-01-01 -Paragraph 23 -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=8&date=2018-03-01&anchor=para_23&doctype=Standard -URIDate 2018-03-16 + Details
Name: | ifrs-full_Assets
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition The amount of assets that the entity (a) expects to realise or intends to sell or consume in its normal operating cycle; (b) holds primarily for the purpose of trading; (c) expects to realise within twelve months after the reporting period; or (d) classifies as cash or cash equivalents (as defined in IAS 7) unless the asset is restricted from being exchanged or used to settle a liability for at least twelve months after the reporting period. [Refer: Assets] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 12 -IssueDate 2018-01-01 -Paragraph B12 -Subparagraph b -Clause i -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=12&date=2018-03-01&anchor=para_B12_b_i&doctype=Appendix&seq=2 -URIDate 2018-03-16 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 1 -IssueDate 2018-01-01 -Paragraph 66 -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=1&date=2018-03-01&anchor=para_66&doctype=Standard -URIDate 2018-03-16 Reference 3: http://www.xbrl.org/2003/role/exampleRef -Name IFRS -Number 12 -IssueDate 2018-01-01 -Paragraph B10 -Subparagraph b -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=12&date=2018-03-01&anchor=para_B10_b&doctype=Appendix&seq=2 -URIDate 2018-03-16 + Details
Name: | ifrs-full_CurrentAssets
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition The amount of liabilities that: (a) the entity expects to settle in its normal operating cycle; (b) the entity holds primarily for the purpose of trading; (c) are due to be settled within twelve months after the reporting period; or (d) the entity does not have an unconditional right to defer settlement for at least twelve months after the reporting period. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 12 -IssueDate 2018-01-01 -Paragraph B12 -Subparagraph b -Clause iii -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=12&date=2018-03-01&anchor=para_B12_b_iii&doctype=Appendix&seq=2 -URIDate 2018-03-16 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 1 -IssueDate 2018-01-01 -Paragraph 69 -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=1&date=2018-03-01&anchor=para_69&doctype=Standard -URIDate 2018-03-16 Reference 3: http://www.xbrl.org/2003/role/exampleRef -Name IFRS -Number 12 -IssueDate 2018-01-01 -Paragraph B10 -Subparagraph b -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=12&date=2018-03-01&anchor=para_B10_b&doctype=Appendix&seq=2 -URIDate 2018-03-16 + Details
Name: | ifrs-full_CurrentLiabilities
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition The current amount of current tax liabilities. [Refer: Current tax liabilities] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 1 -IssueDate 2018-01-01 -Paragraph 54 -Subparagraph n -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=1&date=2018-03-01&anchor=para_54_n&doctype=Standard -URIDate 2018-03-16 + Details
Name: | ifrs-full_CurrentTaxLiabilitiesCurrent
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition The amount of residual interest in the assets of the entity after deducting all its liabilities. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 1 -IssueDate 2018-01-01 -Paragraph 24 -Subparagraph a -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=1&date=2018-03-01&anchor=para_24_a&doctype=Standard -URIDate 2018-03-16 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 1 -IssueDate 2018-01-01 -Paragraph 32 -Subparagraph a -Clause i -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=1&date=2018-03-01&anchor=para_32_a_i&doctype=Standard -URIDate 2018-03-16 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 13 -IssueDate 2018-01-01 -Paragraph 93 -Subparagraph a -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=13&date=2018-03-01&anchor=para_93_a&doctype=Standard -URIDate 2018-03-16 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 13 -IssueDate 2018-01-01 -Paragraph 93 -Subparagraph b -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=13&date=2018-03-01&anchor=para_93_b&doctype=Standard -URIDate 2018-03-16 Reference 5: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 13 -IssueDate 2018-01-01 -Paragraph 93 -Subparagraph e -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=13&date=2018-03-01&anchor=para_93_e&doctype=Standard -URIDate 2018-03-16 Reference 6: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 1 -IssueDate 2018-01-01 -Paragraph 55 -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=1&date=2018-03-01&anchor=para_55&doctype=Standard -URIDate 2018-03-16 Reference 7: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 1 -IssueDate 2018-01-01 -Paragraph 78 -Subparagraph e -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=1&date=2018-03-01&anchor=para_78_e&doctype=Standard -URIDate 2018-03-16 + Details
Name: | ifrs-full_Equity
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition The amount of the entity's equity and liabilities. [Refer: Equity; Liabilities] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 1 -IssueDate 2018-01-01 -Paragraph 55 -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=1&date=2018-03-01&anchor=para_55&doctype=Standard -URIDate 2018-03-16 + Details
Name: | ifrs-full_EquityAndLiabilities
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition The amount of equity attributable to the owners of the parent. This specifically excludes non-controlling interest. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 1 -IssueDate 2018-01-01 -Paragraph 54 -Subparagraph r -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=1&date=2018-03-01&anchor=para_54_r&doctype=Standard -URIDate 2018-03-16 + Details
Name: | ifrs-full_EquityAttributableToOwnersOfParent
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition The amount of present obligations of the entity arising from past events, the settlement of which is expected to result in an outflow from the entity of resources embodying economic benefits. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 13 -IssueDate 2018-01-01 -Paragraph 93 -Subparagraph a -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=13&date=2018-03-01&anchor=para_93_a&doctype=Standard -URIDate 2018-03-16 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 8 -IssueDate 2018-01-01 -Paragraph 28 -Subparagraph d -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=8&date=2018-03-01&anchor=para_28_d&doctype=Standard -URIDate 2018-03-16 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 13 -IssueDate 2018-01-01 -Paragraph 93 -Subparagraph b -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=13&date=2018-03-01&anchor=para_93_b&doctype=Standard -URIDate 2018-03-16 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 13 -IssueDate 2018-01-01 -Paragraph 93 -Subparagraph e -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=13&date=2018-03-01&anchor=para_93_e&doctype=Standard -URIDate 2018-03-16 Reference 5: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 8 -IssueDate 2018-01-01 -Paragraph 23 -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=8&date=2018-03-01&anchor=para_23&doctype=Standard -URIDate 2018-03-16 Reference 6: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 1 -IssueDate 2018-01-01 -Paragraph 55 -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=1&date=2018-03-01&anchor=para_55&doctype=Standard -URIDate 2018-03-16 + Details
Name: | ifrs-full_Liabilities
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition A component of equity representing the entity's cumulative undistributed earnings or deficit. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Name IAS -Number 1 -IssueDate 2018-01-01 -Paragraph 78 -Subparagraph e -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=1&date=2018-03-01&anchor=para_78_e&doctype=Standard -URIDate 2018-03-16 Reference 2: http://www.xbrl.org/2003/role/exampleRef -Name IAS -Number 1 -IssueDate 2018-01-01 -Paragraph IG6 -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=1&date=2018-03-01&anchor=para_IG6&doctype=Implementation%20Guidance -URIDate 2018-03-16 + Details
Name: | ifrs-full_RetainedEarnings
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition The amount of current trade payables and current other payables. [Refer: Current trade payables; Other current payables] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 1 -IssueDate 2018-01-01 -Paragraph 54 -Subparagraph k -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=1&date=2018-03-01&anchor=para_54_k&doctype=Standard -URIDate 2018-03-16 + Details
Name: | ifrs-full_TradeAndOtherCurrentPayables
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition The amount of current trade receivables and current other receivables. [Refer: Current trade receivables; Other current receivables] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 1 -IssueDate 2018-01-01 -Paragraph 54 -Subparagraph h -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=1&date=2018-03-01&anchor=para_54_h&doctype=Standard -URIDate 2018-03-16 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 1 -IssueDate 2018-01-01 -Paragraph 78 -Subparagraph b -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=1&date=2018-03-01&anchor=para_78_b&doctype=Standard -URIDate 2018-03-16 + Details
Name: | ifrs-full_TradeAndOtherCurrentReceivables
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Disclosure of changes in accounting policies, accounting estimates and errors. + References No definition available. + Details
Name: | kt_DisclosureOfChangesInAccountingPoliciesAccountingEstimatesAndErrorsLineItems
Namespace Prefix: | kt_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Details
Name: | ifrs-full_RetrospectiveApplicationAndRetrospectiveRestatementAxis=ifrs-full_PreviouslyStatedMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_RetrospectiveApplicationAndRetrospectiveRestatementAxis=ifrs-full_FinancialEffectOfCorrectionsOfAccountingErrorsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |