| **Earnings (Loss) Per Common Share (Basic Net Income (Loss) per Share) (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands** | 3 Months Ended | 6 Months Ended |
|-------------------------------------------------------------------------------------------------------------------------------------------------------|----------------|----------------|
||
| **Numerator [Abstract]**                                                                                                                              |           |           |   |   |
| Net income (loss) available to common stockholders                                                                                                    | $ 3,415        | $ (15,627)     | $ 4,514 | $ (34,896) |
| Common Stock - Class A [Member]                                                                                                                       |           |           |   |   |
| **Numerator [Abstract]**                                                                                                                              |           |           |   |   |
| Net income (loss) available to common stockholders                                                                                                    | 3,134          | (14,330)       | 4,144 | (32,048) |
| Less: Undistributed net income allocable to participating securities                                                                                  | (167)          | 0              | (210) | 0 |
| Undistributed net income (loss) allocable to common stockholders                                                                                      | $ 2,967        | $ (14,330)     | $ 3,934 | $ (32,048) |
| **Denominator [Abstract]**                                                                                                                            |           |           |   |   |
| Weighted average common shares outstanding                                                                                                            | 33,308         | 34,887         | 33,502 | 35,548 |
| Basic net income (loss) attributable to GCI common stockholders per common share                                                                      | $ 0.09         | $ (0.41)       | $ 0.12 | $ (0.90) |
| Common Stock - Class B [Member]                                                                                                                       |           |           |   |   |
| **Numerator [Abstract]**                                                                                                                              |           |           |   |   |
| Net income (loss) available to common stockholders                                                                                                    | $ 281          | $ (1,297)      | $ 370 | $ (2,848) |
| Less: Undistributed net income allocable to participating securities                                                                                  | 0              | 0              | 0 | 0 |
| Undistributed net income (loss) allocable to common stockholders                                                                                      | $ 281          | $ (1,297)      | $ 370 | $ (2,848) |
| **Denominator [Abstract]**                                                                                                                            |           |           |   |   |
| Weighted average common shares outstanding                                                                                                            | 3,155          | 3,159          | 3,155 | 3,159 |
| Basic net income (loss) attributable to GCI common stockholders per common share                                                                      | $ 0.09         | $ (0.41)       | $ 0.12 | $ (0.90) |

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Undistributed Income (Loss) Available to Common Stockholders
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|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
The amount of net income (loss) for the period per each share of common stock or unit outstanding during the reporting period.
+ References
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| - Definition
Net income after adjustments for dividends on preferred stock (declared in the period) and/or cumulative preferred stock (accumulated for the period).
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| - Definition
Amount of undistributed earnings (loss) allocated to participating securities for the basic earnings (loss) per share or per unit calculation under the two-class method.
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| - Definition
Number of [basic] shares or units, after adjustment for contingently issuable shares or units and other shares or units not deemed outstanding, determined by relating the portion of time within a reporting period that common shares or units have been outstanding to the total time in that period.
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