Name:	atni_GrantFundsUsedToOffsetFixedAssetRelatedCosts
Namespace Prefix:	atni_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

Represents the amount of grants received that offset operating costs.

No definition available.

Name:	atni_GrantFundsUsedToOffsetOperatingExpenses
Namespace Prefix:	atni_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- References

No definition available.

Name:	atni_MobilityFundLineItems
Namespace Prefix:	atni_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

Amount of Mobility Funds received by the entity since inception of the grant.

No definition available.

Name:	atni_MobilityFundsReceived
Namespace Prefix:	atni_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

Amount of Mobility Funds received by the entity since inception of the grant and recorded to date.

No definition available.

Name:	atni_MobilityFundsReceivedAndRecordedToDate
Namespace Prefix:	atni_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

Represents the period over which a portion of the Mobility Funds is used to offset the costs of supporting the networks.

No definition available.

Name:	atni_PeriodOverWhichMobilityFundUsedToOffsetCostsOfSupportingTheNetworks
Namespace Prefix:	atni_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

No definition available.

Name:	us-gaap_LettersOfCreditOutstandingAmount
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

Name:	us-gaap_LongtermDebtTypeAxis=us-gaap_LetterOfCreditMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	atni_TypeOfMobilityFundAxis=atni_WholesaleMobilityFundsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	us-gaap_StatementBusinessSegmentsAxis=atni_UsTelecommunicationsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	us-gaap_BalanceSheetLocationAxis=us-gaap_PropertyPlantAndEquipmentMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	us-gaap_BalanceSheetLocationAxis=us-gaap_OtherCurrentLiabilitiesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: