Description of business and basis of preparation of the consolidated financial statements - CPI (Details)	2 Months Ended	4 Months Ended	8 Months Ended	10 Months Ended	12 Months Ended
Dec. 31, 2015	Apr. 30, 2016	Dec. 31, 2016	Oct. 31, 2015	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Consumer Price Index
Consumer Price Index (annual as a percent)	7.80%	16.60%	16.90%	11.90%	24.80%	36.30%	20.60%
Consumer Price Index (3 years accumulated)					104.90%	103.70%	65.80%
Number of years of accumulated price index					3 years
Internal Wholesale Price Index
Internal Wholesale Price Index (annual as a percent)				10.60%	18.80%	34.60%	19.20%
Internal Wholesale Price Index (3 years accumulated)					90.70%	105.80%	75.40%

No definition available.

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No definition available.

Name:	teo_InternalWholesalePriceIndexAbstract
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Represents the duration of accumulated Price Index under both Consumer price index and wholesale price index.

No definition available.

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Represents the percentage of accumulated Consumer Price Index.

No definition available.

Name:	teo_PercentageOfAccumulatedConsumerPriceIndex
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Represents the percentage of accumulated Wholesale Price Index.

No definition available.

Name:	teo_PercentageOfAccumulatedInternalWholesalePriceIndex
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Represents the percentage of consumer price index over a period.

No definition available.

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Represents the percentage of internal wholesale price Index over a period.

No definition available.

Name:	teo_PercentageOfInternalWholesalePriceIndex
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Data Type:	num:percentItemType
Balance Type:	na
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