v2.4.1.9

Property and Equipment (Details) (USD $) | 12 Months Ended |
--- | --- | ---
Dec. 31, 2013 | Dec. 31, 2014
Cable distribution system | $ 30,498,000,000 cmcsa_CableDistributionSystems | $ 31,655,000,000 cmcsa_CableDistributionSystems
Customer premise equipment | 25,949,000,000 cmcsa_CustomerPremiseEquipment | 27,086,000,000 cmcsa_CustomerPremiseEquipment
Other equipment | 6,826,000,000 us-gaap_PropertyPlantAndEquipmentOther | 7,860,000,000 us-gaap_PropertyPlantAndEquipmentOther
Buildings and leasehold improvements | 8,057,000,000 us-gaap_BuildingsAndImprovementsGross | 8,650,000,000 us-gaap_BuildingsAndImprovementsGross
Land | 1,084,000,000 us-gaap_Land | 1,112,000,000 us-gaap_Land
Property and equipment, at cost | 72,414,000,000 us-gaap_PropertyPlantAndEquipmentGross | 76,363,000,000 us-gaap_PropertyPlantAndEquipmentGross
Less: Accumulated depreciation | 42,574,000,000 us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment | 45,410,000,000 us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment
Property and equipment, net | 29,840,000,000 us-gaap_PropertyPlantAndEquipmentNet | 30,953,000,000 us-gaap_PropertyPlantAndEquipmentNet
NBCUniversal Media, LLC [Member] |  |
Buildings and leasehold improvements | 5,239,000,000 us-gaap_BuildingsAndImprovementsGross / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember | 5,780,000,000 us-gaap_BuildingsAndImprovementsGross / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember
Land | 799,000,000 us-gaap_Land / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember | 820,000,000 us-gaap_Land / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember
Furniture, fixtures and equipment | 2,383,000,000 us-gaap_FurnitureAndFixturesGross / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember | 2,930,000,000 us-gaap_FurnitureAndFixturesGross / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember
Construction in process | 828,000,000 us-gaap_ConstructionInProgressGross / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember | 775,000,000 us-gaap_ConstructionInProgressGross / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember
Property and equipment, at cost | 9,249,000,000 us-gaap_PropertyPlantAndEquipmentGross / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember | 10,305,000,000 us-gaap_PropertyPlantAndEquipmentGross / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember
Less: Accumulated depreciation | 1,599,000,000 us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember | 2,167,000,000 us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember
Property and equipment, net | 7,650,000,000 us-gaap_PropertyPlantAndEquipmentNet / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember | 8,138,000,000 us-gaap_PropertyPlantAndEquipmentNet / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember
Cable Distribution System [Member] |  |
Weighted average original useful life (in years) |  | 11 cmcsa_WeightedAverageOriginalUsefulLife / us-gaap_PropertyPlantAndEquipmentByTypeAxis = cmcsa_CableDistributionSystemMember
Customer Premise Equipment [Member] |  |
Weighted average original useful life (in years) |  | 6 cmcsa_WeightedAverageOriginalUsefulLife / us-gaap_PropertyPlantAndEquipmentByTypeAxis = cmcsa_CustomerPremiseEquipmentMember
Other Equipment [Member] |  |
Weighted average original useful life (in years) |  | 6 cmcsa_WeightedAverageOriginalUsefulLife / us-gaap_PropertyPlantAndEquipmentByTypeAxis = us-gaap_OtherCapitalizedPropertyPlantAndEquipmentMember
Buildings and Leasehold Improvements [Member] |  |
Weighted average original useful life (in years) |  | 22 cmcsa_WeightedAverageOriginalUsefulLife / us-gaap_PropertyPlantAndEquipmentByTypeAxis = us-gaap_BuildingAndBuildingImprovementsMember
Buildings and Leasehold Improvements [Member] | NBCUniversal Media, LLC [Member] |  |
Weighted average original useful life (in years) |  | 21 cmcsa_WeightedAverageOriginalUsefulLife / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember / us-gaap_PropertyPlantAndEquipmentByTypeAxis = us-gaap_BuildingAndBuildingImprovementsMember
Furniture Fixtures And Equipment [Member] | NBCUniversal Media, LLC [Member] |  |
Weighted average original useful life (in years) |  | 7 cmcsa_WeightedAverageOriginalUsefulLife / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember / us-gaap_PropertyPlantAndEquipmentByTypeAxis = us-gaap_FurnitureAndFixturesMember
Comcast Center [Member] |  |
Equity interest acquired | 80.00%us-gaap_BusinessAcquisitionPercentageOfVotingInterestsAcquired / us-gaap_PropertyPlantAndEquipmentByTypeAxis = cmcsa_ComcastCenterMember |
Acquisition Of Real Estate Properties [Member] |  |
Increases in property and equpiment related to real estate acquisitions | 2,200,000,000 us-gaap_PropertyPlantAndEquipmentAdditions / us-gaap_PropertyPlantAndEquipmentByTypeAxis = cmcsa_AcquisitionOfRealEstatePropertiesMember |
Acquisition Of Real Estate Properties [Member] | NBCUniversal Media, LLC [Member] |  |
Increases in property and equpiment related to real estate acquisitions | $ 1,700,000,000 us-gaap_PropertyPlantAndEquipmentAdditions / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember / us-gaap_PropertyPlantAndEquipmentByTypeAxis = cmcsa_AcquisitionOfRealEstatePropertiesMember |

X
- Definition Costs associated with the construction of and improvements to our cable transmission and distribution facilities. + References No definition available. + Details
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- Definition The cost of customer premises equipment. + References No definition available. + Details
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- Definition The weighted average original useful life of long-lived, physical assets used in the normal conduct of business and not intended for resale. + References No definition available. + Details
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- Definition Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services. + 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 (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 + Details
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- Definition Amount before accumulated depreciation of building structures held for productive use including addition, improvement, or renovation to the structure, including, but not limited to, interior masonry, interior flooring, electrical, and plumbing. + 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 -SubTopic 10 -Section 45 -Paragraph 4 -Subparagraph (f) -URI http://asc.fasb.org/extlink&oid=28358313&loc=d3e6812-107765 + Details
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- Definition Percentage of voting equity interests acquired at the acquisition date in the business combination. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=25497992&loc=d3e1392-128463 + Details
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- Definition Amount of structure or a modification to a structure under construction. Includes recently completed structures or modifications to structures that have not been placed into service. + 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 + Details
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- Definition Amount before accumulated depreciation of equipment commonly used in offices and stores that have no permanent connection to the structure of a building or utilities. Examples include, but are not limited to, desks, chairs, tables, and bookcases. + 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 + Details
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