| **Business and Summary of Significant Accounting Principles (Basic EPS calculations) (Details) (USD $)In Thousands, except Per Share data, unless otherwise specified** | 3 Months Ended | 9 Months Ended |
|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------|----------------|----------------|
||
| **Class of Stock [Line Items]**                                                                                                                                         |           |           |   |   |
| Allocation of undistributed earnings                                                                                                                                    | $ 8,905        | $ 3,700        | $ 16,329 | $ 9,111 |
| Common Stock - Class A [Member]                                                                                                                                         |           |           |   |   |
| **Class of Stock [Line Items]**                                                                                                                                         |           |           |   |   |
| Allocation of undistributed earnings                                                                                                                                    | 8,211          | 3,419          | 15,070 | 8,420 |
| Weighted average common shares outstanding                                                                                                                              | 37,434         | 38,600         | 37,887 | 38,614 |
| Basic net income attributable to GCI common stockholders per common share (USD per share)                                                                               | $ 0.22         | $ 0.09         | $ 0.40 | $ 0.22 |
| Common Stock - Class B [Member]                                                                                                                                         |           |           |   |   |
| **Class of Stock [Line Items]**                                                                                                                                         |           |           |   |   |
| Allocation of undistributed earnings                                                                                                                                    | $ 694          | $ 281          | $ 1,259 | $ 691 |
| Weighted average common shares outstanding                                                                                                                              | 3,166          | 3,170          | 3,167 | 3,170 |
| Basic net income attributable to GCI common stockholders per common share (USD per share)                                                                               | $ 0.22         | $ 0.09         | $ 0.40 | $ 0.22 |

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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
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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