| **Business and Summary of Significant Accounting Principles (Balance Sheets Immaterial Error Correction) (Details) (USD $)In Thousands, unless otherwise specified** | Dec. 31, 2012 | Dec. 31, 2011 | Dec. 31, 2010 | Dec. 31, 2009 |
|----------------------------------------------------------------------------------------------------------------------------------------------------------------------|---------------|---------------|---------------|---------------|
| Property and equipment in service net of depreciation                                                                                                                | $ 838,247     | $ 849,121     |          |          |
| Net property and equipment                                                                                                                                           | 932,665       | 892,039       |          |          |
| Total assets                                                                                                                                                         | 1,506,522     | 1,446,320     |          |          |
| Deferred income taxes                                                                                                                                                | 123,661       | 114,234       |          |          |
| Total liabilities                                                                                                                                                    | 1,317,086     | 1,272,673     |          |          |
| Retained earnings                                                                                                                                                    | 107,584       | 97,911        | 92,200        | 83,589        |
| Total General Communication, Inc. stockholders' equity                                                                                                               | 157,178       | 157,339       |          |          |
| Total stockholders' equity                                                                                                                                           | 189,436       | 173,647       | 199,099       | 265,255       |
| Total liabilities and stockholders' equity                                                                                                                           | 1,506,522     | 1,446,320     |          |          |
| Scenario As Previously Reported [Member]                                                                                                                             |          |          |          |          |
| Property and equipment in service net of depreciation                                                                                                                |          | 851,705       |          |          |
| Net property and equipment                                                                                                                                           |          | 894,623       |          |          |
| Total assets                                                                                                                                                         |          | 1,448,904     |          |          |
| Deferred income taxes                                                                                                                                                |          | 115,296       |          |          |
| Total liabilities                                                                                                                                                    |          | 1,273,735     |          |          |
| Retained earnings                                                                                                                                                    |          | 99,433        | 93,607        | 84,651        |
| Total General Communication, Inc. stockholders' equity                                                                                                               |          | 158,861       |          |          |
| Total stockholders' equity                                                                                                                                           |          | 175,169       | 200,506       | 266,317       |
| Total liabilities and stockholders' equity                                                                                                                           |          | 1,448,904     |          |          |
| Adjustment [Member]                                                                                                                                                  |          |          |          |          |
| Property and equipment in service net of depreciation                                                                                                                |          | (2,584)       |          |          |
| Net property and equipment                                                                                                                                           |          | (2,584)       |          |          |
| Total assets                                                                                                                                                         |          | (2,584)       |          |          |
| Deferred income taxes                                                                                                                                                |          | (1,062)       |          |          |
| Total liabilities                                                                                                                                                    |          | (1,062)       |          |          |
| Retained earnings                                                                                                                                                    |          | (1,522)       | (1,407)       | (1,062)       |
| Total General Communication, Inc. stockholders' equity                                                                                                               |          | (1,522)       |          |          |
| Total stockholders' equity                                                                                                                                           |          | (1,522)       | (1,407)       | (1,062)       |
| Total liabilities and stockholders' equity                                                                                                                           |          | $ (2,584)     |          |          |

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|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Tangible assets that are held by an entity and have been placed into service for use in the production or supply of goods and services, for rental to others, or for administrative purposes and that are expected to provide economic benefit for more than one year; net of accumulated depreciation. Examples include land, buildings, and production equipment. Excludes Construction in Progress.
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|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Sum of the carrying amounts as of the balance sheet date of all assets that are recognized. Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.
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|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount of deferred tax liability attributable to taxable temporary differences, net of deferred tax asset attributable to deductible temporary differences and carryforwards net of valuation allowances expected to be realized or consumed after one year (or the normal operating cycle, if longer).
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|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Sum of the carrying amounts as of the balance sheet date of all liabilities that are recognized. Liabilities are probable future sacrifices of economic benefits arising from present obligations of an entity to transfer assets or provide services to other entities in the future.
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|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Total of all Liabilities and Stockholders' Equity items (or Partners' Capital, as applicable), including the portion of equity attributable to noncontrolling interests, if any.
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|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount, net of accumulated depreciation, depletion and amortization, of long-lived physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.
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| - Definition
The cumulative amount of the reporting entity's undistributed earnings or deficit.
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|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Total of all stockholders' equity (deficit) items, net of receivables from officers, directors, owners, and affiliates of the entity which are attributable to the parent. The amount of the economic entity's stockholders' equity attributable to the parent excludes the amount of stockholders' equity which is allocable to that ownership interest in subsidiary equity which is not attributable to the parent (noncontrolling interest, minority interest). This excludes temporary equity and is sometimes called permanent equity.
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|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount of stockholders' equity (deficit), net of receivables from officers, directors, owners, and affiliates of the entity, attributable to both the parent and noncontrolling interests. Amount excludes temporary equity. Alternate caption for the concept is permanent equity.
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