Represents addition of debt in a business combination.

No definition available.

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- Definition

Amount of write-down of assets recognized in the income statement. Includes, but is not limited to, losses from tangible assets, intangible assets and goodwill.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section 45
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=68055307&loc=d3e2420-110228

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3602-108585

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- Definition

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.

+ References

No definition available.

+ Details

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- Definition

The pro forma basic net income per share for a period as if the business combination or combinations had been completed at the beginning of a period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (h)(2)-(3)
-URI http://asc.fasb.org/extlink&oid=65885119&loc=d3e1392-128463

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- Definition

The pro forma diluted net income per share for a period as if the business combination or combinations had been completed at the beginning of a period.

+ References

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- References

No definition available.

+ Details

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- Definition

The pro forma net Income or Loss for the period as if the business combination or combinations had been completed at the beginning of a period.

+ References

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
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- Definition

The pro forma revenue for a period as if the business combination or combinations had been completed at the beginning of the period.

+ References

+ Details

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Balance Type:	credit
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- Definition

Gross amount of debt extinguished.

+ References

No definition available.

+ Details

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ACQUISITIONS AND DISPOSITIONS - Pro Forma Results (Details) - USD ($) $ / shares in Units, $ in Thousands		12 Months Ended
	Jul. 01, 2016	Dec. 31, 2016	Dec. 31, 2015
Pro forma
Acquisitions
Impairment charges		$ 5,400	$ 168,700
Pro Forma
Revenue		535,628	546,589
Net income (loss) attributable to ATN International, Inc. Stockholders		$ 14,660	$ (97,102)
Earnings per share: Basic (in dollars per share)		$ 0.91	$ (6.06)
Earnings per share: Diluted (in dollars per share)		$ 0.90	$ (6.02)
As reported
Pro Forma
Revenue		$ 457,003	$ 355,369
Net income (loss) attributable to ATN International, Inc. Stockholders		$ 12,101	$ 16,940
Earnings per share: Basic (in dollars per share)		$ 0.75	$ 1.06
Earnings per share: Diluted (in dollars per share)		$ 0.75	$ 1.05
One Communications (formerly KeyTech)
Acquisitions
Retirement of debt		$ 24,700
One Communications (formerly KeyTech) \| Pro forma
Acquisitions
Impairment charges		4,300	$ 85,600
Innovative
Acquisitions
Retirement of debt		185,800
Addition of debt	$ 60,000
Innovative \| Pro forma
Acquisitions
Impairment charges		$ 1,100	$ 83,100