| **Tower Sale and Leaseback (Future Minimum Payments) (Details) $ in Thousands** | Dec. 31, 2016 USD ($) |
|---------------------------------------------------------------------------------|-----------------------|
| **Tower Sale and Leaseback [Abstract]**                                         |                  |
| 2017                                                                            | $ 6,996               |
| 2018                                                                            | 7,136                 |
| 2019                                                                            | 7,279                 |
| 2020                                                                            | 7,425                 |
| 2021                                                                            | 7,573                 |
| 2022 and thereafter                                                             | 150,117               |
| Total minimum payments                                                          | 186,526               |
| Less amount representing interest                                               | 96,722                |
| Tower obligation                                                                | $ 89,804              |

| X                                                                                                                                                                                                                                                     |
|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Tower Sale and Leaseback  [Abstract]
+ References
No definition available.
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                            |
|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount necessary to reduce minimum lease payments to present value for sale-leaseback transactions accounted for using the deposit method or as a financing.
+ References
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| - Definition
Amount of minimum lease payments for sale-leaseback transactions accounted for using the deposit method or as a financing.
+ References
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|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount of minimum lease payments for sale-leaseback transactions accounted for using the deposit method or as a financing due after the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.
+ References
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|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount of minimum lease payments for sale-leaseback transactions accounted for using the deposit method or as a financing due in the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.
+ References
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| - Definition
Amount of minimum lease payments for sale-leaseback transactions accounted for using the deposit method or as a financing due in the fourth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.
+ References
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| - Definition
Amount of minimum lease payments for sale-leaseback transactions accounted for using the deposit method or as a financing due in the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.
+ References
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| - Definition
Amount of minimum lease payments for sale-leaseback transactions accounted for using the deposit method or as a financing due in the third fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.
+ References
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| - Definition
Amount of minimum lease payments for sale-leaseback transactions accounted for using the deposit method or as a financing due in the second fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.
+ References
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| - Definition
Present value of minimum lease payments for sale-leaseback transactions accounted for using the deposit method or as a financing.
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