| **Stockholders' Equity (Narratives) (Details) $ / shares in Units, $ in Thousands** | 12 Months Ended                                                                                                                                     |
|-------------------------------------------------------------------------------------|-----------------------------------------------------------------------------------------------------------------------------------------------------|
||
| **Common Stock**                                                                    |                                                                                                                                                |   |   |
| Stock Repurchased and Retired During Period, Value                                  | $ 58,679                                                                                                                                            | $ 53,774 | $ 6,850 |
| **Share-Based Compensation**                                                        |                                                                                                                                                |   |   |
| Fair value assumptions, method used                                                 | The fair value of restricted stock awards is determined based on the number of shares granted and the quoted price of our common stock.   |   |   |
| Share-based compensation expense                                                    | $ 11,000                                                                                                                                            | 10,900 | 8,400 |
| Unrecognized share-based compensation expense                                       | 12,500                                                                                                                                              |   |   |
| **GCI 401(k) Plan**                                                                 |                                                                                                                                                |   |   |
| Matching contributions                                                              | $ 11,000                                                                                                                                            | $ 9,800 | $ 9,100 |
| Class A Common Stock                                                                |                                                                                                                                                |   |   |
| **Common Stock**                                                                    |                                                                                                                                                |   |   |
| Common stock, voting rights, number of votes | vote                                 | 1                                                                                                                                                   |   |   |
| Stock conversion ratio                                                              | 1                                                                                                                                                   |   |   |
| Class B Common Stock                                                                |                                                                                                                                                |   |   |
| **Common Stock**                                                                    |                                                                                                                                                |   |   |
| Common stock, voting rights, number of votes | vote                                 | 10                                                                                                                                                  |   |   |
| Restricted Stock                                                                    |                                                                                                                                                |   |   |
| **Share-Based Compensation**                                                        |                                                                                                                                                |   |   |
| Weighted average period for recognition of unvested shares                          | 2 years                                                                                                                                             |   |   |
| Maximum | Restricted Stock                                                          |                                                                                                                                                |   |   |
| **Share-Based Compensation**                                                        |                                                                                                                                                |   |   |
| Vesting period                                                                      | 3 years                                                                                                                                             |   |   |
| Stock Option Plan [Member] | Class A Common Stock                                   |                                                                                                                                                |   |   |
| **Share-Based Compensation**                                                        |                                                                                                                                                |   |   |
| Number of shares authorized | shares                                                | 15,700,000.0                                                                                                                                        |   |   |
| Number of shares available for grant | shares                                       | 1,500,000                                                                                                                                           |   |   |
| Stock Option Plan [Member] | Restricted Stock                                       |                                                                                                                                                |   |   |
| **Share-Based Compensation**                                                        |                                                                                                                                                |   |   |
| Granted (USD per share) | $ / shares                                                | $ 17.87                                                                                                                                             | $ 15.06 | $ 10.04 |
| Fair value of awards vesting                                                        | $ 13,500                                                                                                                                            | $ 17,000 | $ 8,500 |
| Stock Buyback Program [Member]                                                      |                                                                                                                                                |   |   |
| **Common Stock**                                                                    |                                                                                                                                                |   |   |
| Stock Repurchase Program, Authorized Amount Per Quarter                             | $ 5,000                                                                                                                                             |   |   |
| Stock Repurchased and Retired During Period, Shares | shares                        | 3,500,000                                                                                                                                           | 3,000,000 | 400,000 |
| Stock Repurchase Program, Remaining Authorized Repurchase Amount                    | $ 60,300                                                                                                                                            |   |   |
| Stock Buyback Program [Member] | Class A Common Stock                               |                                                                                                                                                |   |   |
| **Common Stock**                                                                    |                                                                                                                                                |   |   |
| Stock Repurchased and Retired During Period, Value                                  | $ 55,200                                                                                                                                            | $ 47,400 | $ 4,200 |

| X                                                                                                                                                                                                                                                                    |
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Common Stock, Voting Rights, Number of Votes
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Stock Repurchase Program, Authorized Amount Per Quarter
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| - Definition
Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.
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Amount of discretionary contributions made by an employer to a defined contribution plan.
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| - Definition
Unrecognized cost of unvested share-based compensation awards.
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| - Definition
Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.
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| - Definition
Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.
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| - Definition
The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).
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| - Definition
Fair value of share-based awards for which the grantee gained the right by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash.
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| - Definition
For each plan, identification of the award pricing model or other valuation method used in calculating the weighted average fair values disclosed. The model is also used to calculate the compensation expense that is shown within the balance sheet, income statement, and cash flow. Examples of valuation techniques are lattice models (binomial model), closed-form models (Black-Scholes-Merton formula), and a Monte Carlo simulation technique. Fair value is the amount at which an asset or liability could be bought or incurred or sold or settled in a current transaction between willing parties, that is, other than in a forced or liquidation sale. May include disclosures about the assumptions underlying application of the method selected.
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| - Definition
The maximum number of shares (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units remain authorized and become reserved for issuance under outstanding awards (not necessarily vested).
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|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.
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| - Definition
Amount remaining of a stock repurchase plan authorized.
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| - Definition
Number of shares that have been repurchased and retired during the period.
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| - Definition
Equity impact of the value of stock that has been repurchased and retired during the period. The excess of the purchase price over par value can be charged against retained earnings (once the excess is fully allocated to additional paid in capital).
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Ratio applied to the conversion of stock split, for example but not limited to, one share converted to two or two shares converted to one.
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