Summary of Significant Accounting Policies (Details 1) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013
Property, Plant and Equipment [Line Items]
Property Plant and Equipment, Gross	$ 161,602us-gaap_PropertyPlantAndEquipmentGross	$ 158,762us-gaap_PropertyPlantAndEquipmentGross
Accumulated depreciation	(106,415)	(102,425)
Net property and equipment	55,187us-gaap_PropertyPlantAndEquipmentNet	56,337us-gaap_PropertyPlantAndEquipmentNet
Land and Land Improvements [Member]
Property, Plant and Equipment [Line Items]
Property Plant and Equipment, Gross	11,026	10,984
Estimated Useful Life	0 years
Building [Member]
Property, Plant and Equipment [Line Items]
Property Plant and Equipment, Gross	33,275	32,378
Estimated Useful Life	31 years 6 months
Towers And Antennae [Member]
Property, Plant and Equipment [Line Items]
Property Plant and Equipment, Gross	26,191	25,761
Towers And Antennae [Member] \| Minimum [Member]
Property, Plant and Equipment [Line Items]
Estimated Useful Life	7 years
Towers And Antennae [Member] \| Maximum [Member]
Property, Plant and Equipment [Line Items]
Estimated Useful Life	15 years
Equipment [Member]
Property, Plant and Equipment [Line Items]
Property Plant and Equipment, Gross	79,216	77,908
Equipment [Member] \| Minimum [Member]
Property, Plant and Equipment [Line Items]
Estimated Useful Life	3 years
Equipment [Member] \| Maximum [Member]
Property, Plant and Equipment [Line Items]
Estimated Useful Life	15 years
Furniture and Fixtures [Member]
Property, Plant and Equipment [Line Items]
Property Plant and Equipment, Gross	8,104	7,926
Furniture and Fixtures [Member] \| Minimum [Member]
Property, Plant and Equipment [Line Items]
Estimated Useful Life	7 years
Furniture and Fixtures [Member] \| Maximum [Member]
Property, Plant and Equipment [Line Items]
Estimated Useful Life	20 years
Vehicles [Member]
Property, Plant and Equipment [Line Items]
Property Plant and Equipment, Gross	$ 3,790	$ 3,805
Estimated Useful Life	5 years

Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 360

-SubTopic 10

-Section 50

-Paragraph 1

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=6391035&loc=d3e2868-110229

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.14)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 14

-Article 5

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- Definition

Amount before accumulated depreciation, depletion and amortization of 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, and furniture and fixtures.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 360

-SubTopic 10

-Section 50

-Paragraph 1

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=6391035&loc=d3e2868-110229

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

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-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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Amount after accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business to produce goods and services and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

+ 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=d3e2868-110229

Reference 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=d3e13212-122682

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

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-Subparagraph a

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Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

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Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

+ References

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