| **Net Property and Equipment in Service (Tables)** | 12 Months Ended                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    |
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| **Property, Plant and Equipment [Abstract]**       |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               |
| Schedule of Net Property and Equipment in Service  | Net property and equipment in service consists of the following at December 31, 2014 and 2013 (amounts in thousands): 2014 2013Land and buildings$100,038 69,984Telephony transmission equipment and distribution facilities1,189,470 1,085,963Cable transmission equipment and distribution facilities193,832 177,410Studio equipment14,396 12,680Support equipment and systems270,629 245,301Transportation equipment15,667 13,619Customer premise equipment153,039 149,372Fiber optic cable systems305,200 299,525 2,242,271 2,053,854Less accumulated depreciation1,178,982 1,042,724Less accumulated amortization50,047 41,552Net property and equipment in service$1,013,242 969,578    Property and equipment under capital leases$112,495 104,251 |

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| - Definition
Tabular disclosure of physical assets used in the normal conduct of business and not intended for resale. Includes, but is not limited to, balances by class of assets, depreciation and depletion expense and method used, including composite depreciation, and accumulated deprecation.
+ References
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 360 -SubTopic 10 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6391035&loc=d3e2868-110229Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.13) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 13 -Subparagraph b -Article 5
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