| **Business and Summary of Significant Accounting Principles (Diluted EPS calculations) (Details) (USD $)In Thousands, except Per Share data, unless otherwise specified** | 3 Months Ended | 6 Months Ended |
|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------|----------------|----------------|
||
| **Class of Stock [Line Items]**                                                                                                                                           |           |           |   |   |
| Allocation of undistributed earnings for basic computation                                                                                                                | $ 8,155        | $ 4,180        | $ 10,276 | $ 7,424 |
| Common Stock - Class A [Member]                                                                                                                                           |           |           |   |   |
| **Class of Stock [Line Items]**                                                                                                                                           |           |           |   |   |
| Allocation of undistributed earnings for basic computation                                                                                                                | 7,534          | 3,862          | 9,490 | 6,855 |
| Reallocation of undistributed earnings as a result of conversion of Class B to Class A shares                                                                             | 621            | 318            | 786 | 569 |
| Reallocation of undistributed earnings as a result of conversion of dilutive securities                                                                                   | 0              | 0              | 0 | 0 |
| Effect of share based compensation that may be settled in cash or shares                                                                                                  | (9)            | (60)           | (2) | (94) |
| Net income adjusted for allocation of undistributed earnings and effect of share based compensation that may be settled in cash or shares                                 | 8,146          | 4,120          | 10,274 | 7,330 |
| Number of shares used in basic computation                                                                                                                                | 38,383         | 37,979         | 38,186 | 38,117 |
| Conversion of Class B to Class A common shares outstanding                                                                                                                | 3,162          | 3,132          | 3,162 | 3,167 |
| Unexercised stock options                                                                                                                                                 | 122            | 164            | 121 | 168 |
| Effect of share based compensation that may be settled in cash or shares                                                                                                  | 26             | 90             | 26 | 90 |
| Number of shares used in per share computation                                                                                                                            | 41,693         | 41,365         | 41,495 | 41,542 |
| Diluted net income attributable to General Communication, Inc. common stockholders per common share (USD per share)                                                       | $ 0.20         | $ 0.10         | $ 0.25 | $ 0.18 |
| Common Stock - Class B [Member]                                                                                                                                           |           |           |   |   |
| **Class of Stock [Line Items]**                                                                                                                                           |           |           |   |   |
| Allocation of undistributed earnings for basic computation                                                                                                                | 621            | 318            | 786 | 569 |
| Reallocation of undistributed earnings as a result of conversion of Class B to Class A shares                                                                             | 0              | 0              | 0 | 0 |
| Reallocation of undistributed earnings as a result of conversion of dilutive securities                                                                                   | (3)            | (6)            | (3) | (10) |
| Effect of share based compensation that may be settled in cash or shares                                                                                                  | 0              | 0              | 0 | 0 |
| Net income adjusted for allocation of undistributed earnings and effect of share based compensation that may be settled in cash or shares                                 | $ 618          | $ 312          | $ 783 | $ 559 |
| Number of shares used in basic computation                                                                                                                                | 3,162          | 3,132          | 3,163 | 3,167 |
| Conversion of Class B to Class A common shares outstanding                                                                                                                | 0              | 0              | 0 | 0 |
| Unexercised stock options                                                                                                                                                 | 0              | 0              | 0 | 0 |
| Effect of share based compensation that may be settled in cash or shares                                                                                                  | 0              | 0              | 0 | 0 |
| Number of shares used in per share computation                                                                                                                            | 3,162          | 3,132          | 3,163 | 3,167 |
| Diluted net income attributable to General Communication, Inc. common stockholders per common share (USD per share)                                                       | $ 0.20         | $ 0.10         | $ 0.25 | $ 0.18 |

| X                                                                                                                                                                                                                                                                                                                                                                                                                                        |
|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Additional shares included in the calculation of diluted EPS as a result of the potentially dilutive effect of convertible class B stock using if-converted method.
+ References
No definition available.
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                          |
|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Additional shares included in the calculation of diluted EPS as a result of the potentially dilutive effect of deferred compensation payment arrangements using the treasury stock method.
+ References
No definition available.
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                          |
|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount of increase (decrease) to net income used for calculating diluted earnings per share (EPS), resulting from the assumed exercise of dilutive convertible securities excluding adjustments related to ESOP convertible preferred stock, stock options, and restrictive stock units.
+ References
No definition available.
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|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
The amount of net income (loss) for the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period.
+ References
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|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Additional shares included in the calculation of diluted EPS as a result of the potentially dilutive effect of share based payment arrangements using the treasury stock method.
+ References
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       |
|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Net income after adjustments for dividends on preferred stock (declared in the period) and/or cumulative preferred stock (accumulated for the period).
+ References
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|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Net Income or Loss Available to Common Stockholders plus adjustments resulting from the assumption that dilutive convertible securities were converted, options or warrants were exercised, or that other shares were issued upon the satisfaction of certain conditions.
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       |
|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Aggregate of earnings distributed and earnings allocated to participating securities under the two-class method to the extent that participating securities may share in earnings as if all of the earnings for the period had been distributed.
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No definition available.
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                |
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| - Definition
Earnings allocated (not distributed) to participating securities under the two-class method to the extent that participating securities may share in earnings as if all of the earnings for the period had been distributed.
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No definition available.
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|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
The average number of shares or units issued and outstanding that are used in calculating diluted EPS or earnings per unit (EPU), determined based on the timing of issuance of shares or units in the period.
+ References
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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.
+ References
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