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Represents the period for which litigation proceedings and other disputes, while not conclusively resolved, have not been the subject of discussions or other significant activity.

No definition available.

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Represents the amount of punitive damages that the plaintiff seeks in the legal matter.

No definition available.

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Balance Type:	credit
Period Type:	instant

Represents the amount of renewal fee of telecommunications license.

No definition available.

Name:	atni_LossContingencyRenewalFeeOfTelecommunicationsLicense
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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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Represents the amount of spectrum fees paid as full settlement.

No definition available.

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

No definition available.

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The fee, expressed as a percentage of the line of credit facility, for available but unused credit capacity under the credit facility.

No definition available.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

No definition available.

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Amount of loss contingency liability.

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The value (monetary amount) of the award the plaintiff seeks in the legal matter.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=25496072&loc=d3e14326-108349

Reference 2: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
-Topic 450
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Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
-Paragraph 4
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Reflects the estimated amount of loss from the specified contingency as of the balance sheet date.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
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-Publisher FASB
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-URI http://asc.fasb.org/extlink&oid=25496072&loc=d3e14557-108349

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

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Name:	us-gaap_LongtermDebtTypeAxis=us-gaap_LetterOfCreditMember
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Name:	atni_TypeOfMobilityFundAxis=atni_UniversalServiceAdministrativeCompanyMember
Namespace Prefix:
Data Type:	na
Balance Type:
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Name:	us-gaap_LitigationCaseAxis=atni_LawsuitFiledByCaribbeanTelecommunicationsLimitedMember
Namespace Prefix:
Data Type:	na
Balance Type:
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Name:	us-gaap_LitigationCaseAxis=atni_LitigationProceedingsAndDisputesInGuyanaMember
Namespace Prefix:
Data Type:	na
Balance Type:
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