| **Long Term Debt (Schedule of Long Term Debt) (Details) $ in Thousands**                                                                | 12 Months Ended |             |          |
|-----------------------------------------------------------------------------------------------------------------------------------------|-----------------|-------------|----------|
||
| **Debt Instrument [Line Items]**                                                                                                        |            |        |     |
| Long-term debt, gross                                                                                                                   | $ 1,373,783     | $ 1,372,113 |     |
| Less unamortized discount                                                                                                               | 21,878          | 24,007      |     |
| Less unamortized deferred loan fees                                                                                                     | 15,133          | 15,368      |     |
| Less current portion of long-term debt                                                                                                  | 3,326           | 3,342       |     |
| Long-term debt, net                                                                                                                     | $ 1,333,446     | 1,329,396   |     |
| 2025 Notes | Senior Notes [Member]                                                                                                      |            |        |     |
| **Debt Instrument [Line Items]**                                                                                                        |            |        |     |
| Stated percentage                                                                                                                       | 6.875%          |        |     |
| Long-term debt, gross                                                                                                                   | $ 450,000       | 450,000     |     |
| 2021 Notes | Senior Notes [Member]                                                                                                      |            |        |     |
| **Debt Instrument [Line Items]**                                                                                                        |            |        |     |
| Stated percentage                                                                                                                       | 6.75%           |        |     |
| Long-term debt, gross                                                                                                                   | $ 325,000       | 325,000     |     |
| Searchlight ALX, LP Promissory Note [Member] | Unsecured Debt [Member]                                                                  |            |        |     |
| **Debt Instrument [Line Items]**                                                                                                        |            |        |     |
| Stated percentage                                                                                                                       | 7.50%           |        |     |
| Long-term debt, gross                                                                                                                   | $ 75,000        | 75,000      |     |
| Less unamortized discount                                                                                                               |            |        | $ 21,700 |
| Wells Fargo Note | Notes Payable to Banks                                                                                               |            |        |     |
| **Debt Instrument [Line Items]**                                                                                                        |            |        |     |
| Long-term debt, gross                                                                                                                   | $ 8,596         | 9,176       |     |
| Term Loan B | Senior Credit Facility | Medium-term Notes [Member]                                                                       |            |        |     |
| **Debt Instrument [Line Items]**                                                                                                        |            |        |     |
| Principal payments (as a percent)                                                                                                       | 0.25%           |        |     |
| Long-term debt, gross                                                                                                                   | $ 245,187       | 272,937     |     |
| Term Loan A | Senior Credit Facility | Medium-term Notes [Member]                                                                       |            |        |     |
| **Debt Instrument [Line Items]**                                                                                                        |            |        |     |
| Long-term debt, gross                                                                                                                   | 215,000         | 240,000     |     |
| Revolving Credit Facility | Senior Credit Facility | Line of Credit [Member]                                                            |            |        |     |
| **Debt Instrument [Line Items]**                                                                                                        |            |        |     |
| Long-term debt, gross                                                                                                                   | $ 55,000        | $ 0         |     |
| London Interbank Offered Rate (LIBOR) [Member] | Wells Fargo Note | Notes Payable to Banks                                              |            |        |     |
| **Debt Instrument [Line Items]**                                                                                                        |            |        |     |
| Basis spread on variable rate (as a percent)                                                                                            | 2.25%           |        |     |
| London Interbank Offered Rate (LIBOR) [Member] | Term Loan B | Senior Credit Facility | Medium-term Notes [Member]                      |            |        |     |
| **Debt Instrument [Line Items]**                                                                                                        |            |        |     |
| Basis spread on variable rate (as a percent)                                                                                            | 3.00%           |        |     |
| Minimum                                                                                                                                 |            |        |     |
| **Debt Instrument [Line Items]**                                                                                                        |            |        |     |
| Interest coverage ratio                                                                                                                 | 2.50            |        |     |
| Minimum | London Interbank Offered Rate (LIBOR) [Member] | Term Loan A | Senior Credit Facility | Medium-term Notes [Member]            |            |        |     |
| **Debt Instrument [Line Items]**                                                                                                        |            |        |     |
| Basis spread on variable rate (as a percent)                                                                                            | 2.00%           |        |     |
| Minimum | London Interbank Offered Rate (LIBOR) [Member] | Revolving Credit Facility | Senior Credit Facility | Line of Credit [Member] |            |        |     |
| **Debt Instrument [Line Items]**                                                                                                        |            |        |     |
| Basis spread on variable rate (as a percent)                                                                                            | 2.00%           |        |     |
| Maximum                                                                                                                                 |            |        |     |
| **Debt Instrument [Line Items]**                                                                                                        |            |        |     |
| Total leverage ratio                                                                                                                    | 5.95            |        |     |
| Senior leverage ratio                                                                                                                   | 3.00            |        |     |
| Maximum | London Interbank Offered Rate (LIBOR) [Member] | Term Loan A | Senior Credit Facility | Medium-term Notes [Member]            |            |        |     |
| **Debt Instrument [Line Items]**                                                                                                        |            |        |     |
| Basis spread on variable rate (as a percent)                                                                                            | 3.00%           |        |     |
| Maximum | London Interbank Offered Rate (LIBOR) [Member] | Revolving Credit Facility | Senior Credit Facility | Line of Credit [Member] |            |        |     |
| **Debt Instrument [Line Items]**                                                                                                        |            |        |     |
| Basis spread on variable rate (as a percent)                                                                                            | 3.00%           |        |     |

| X                                                                                                                                                                                                                                                                                       |
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| - Definition
Percentage points added to the reference rate to compute the variable rate on the debt instrument.
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|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.
+ References
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                 |
|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Contractual interest rate for funds borrowed, under the debt agreement.
+ References
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| - Definition
Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.
+ References
No definition available.
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|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount, after accumulated amortization, of debt discount.
+ References
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|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount, after accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.
+ References
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|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt, classified as current. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.
+ References
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| - Definition
Amount after unamortized (discount) premium and debt issuance costs of long-term debt classified as noncurrent and excluding amounts to be repaid within one year or the normal operating cycle, if longer. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.
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