OTHER RECEIVABLES - Movements in the allowances (Details) - Other current receivables - ARS ($) $ in Millions	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019
Movements in the allowances of other receivables
At the beginning of the fiscal year	$ (51)	$ (37)
Increases	(297)	(26)
Decreases (includes RECPAM)	15	12
At the end of the year	$ (333)	$ (51)

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]

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Note Expiry date 2021-01-01
-Name IFRS
-Number 7
-IssueDate 2020-01-01
-Paragraph 16
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=7&code=ifrs-tx-2017-en-b&anchor=para_16&doctype=Standard&book=b
-URIDate 2020-01-01

+ Details

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

- 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 2020-01-01
-Paragraph 16
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=7&code=ifrs-tx-2017-en-b&anchor=para_16&doctype=Standard&book=b
-URIDate 2020-01-01

+ Details

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Namespace Prefix:	ifrs-full_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The decrease in an allowance account for credit losses of financial assets resulting from the utilisation of the allowance. [Refer: Allowance account for credit losses of financial assets]

+ References

+ Details

Name:	ifrs-full_UtilisationAllowanceAccountForCreditLossesOfFinancialAssets
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- 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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Namespace Prefix:	teo_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Details

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Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: