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