XML 188 R136.htm IDEA: XBRL DOCUMENT v3.20.1

Borrowings - Summary of Long-term Borrowings (Parenthetical) (Detail) - ₩ / shares	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2010
Inter-Korean Cooperation Fund [member]
Disclosure of detailed information about borrowings [line items]
Long term debt repayment	The above Inter-Korean Cooperation Fund is repayable in installments over 13 years after a seven-year grace period.
Vessel facility loans [member] | Shinhan Bank [member]
Disclosure of detailed information about borrowings [line items]
LIBOR rate	1.908%
Vessel facility loans [member] | Kookmin Bank [member]
Disclosure of detailed information about borrowings [line items]
LIBOR rate	1.908%
Redeemable convertible preferred stock [member]
Disclosure of detailed information about borrowings [line items]
Shares issued		1,900,000
Par value per share		₩ 500

X

- Definition

The adjustment to the basis (reference rate) used for calculation of the interest rate on borrowings. [Refer: Borrowings]

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name IFRS
-Number 7
-IssueDate 2019-01-01
-Paragraph 7
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=7&code=ifrs-tx-2019-en-r&anchor=para_7&doctype=Standard
-URIDate 2019-03-27

+ Details

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Balance Type:	na
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

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X

- Definition

The number of shares issued by the entity.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name IAS
-Number 1
-IssueDate 2019-01-01
-Paragraph 106
-Subparagraph d
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=1&code=ifrs-tx-2019-en-r&anchor=para_106_d&doctype=Standard
-URIDate 2019-03-27

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Period Type:	instant

X

- Definition

The nominal value per share.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 1
-IssueDate 2019-01-01
-Paragraph 79
-Subparagraph a
-Clause iii
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=1&code=ifrs-tx-2019-en-r&anchor=para_79_a_iii&doctype=Standard
-URIDate 2019-03-27

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Balance Type:	na
Period Type:	instant

X

- Definition

Long term debt repayment description.

+ References

No definition available.

+ Details

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Namespace Prefix:	kt_
Data Type:	xbrli:stringItemType
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- Details

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Namespace Prefix:
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- Details

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- Details

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Namespace Prefix:
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X

- Details

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- Details

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