Acquisition (Pro Forma Revenue and Net Earnings) (Details) - HoldCo - GCI Liberty - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2018	Mar. 31, 2017
Business Acquisition [Line Items]
Revenue	$ 220,805	$ 229,292
Net earnings (loss)	(197,096)	451,616
Net earnings (loss) attributable to GCI, LLC shareholder	$ (196,941)	$ 451,733

Business Acquisition, Pro Forma Net Income (Loss) Attributable To Common Shareholders

No definition available.

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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 net Income or Loss for the 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=79982066&loc=d3e1392-128463

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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

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