Annual report pursuant to Section 13 and 15(d)

Goodwill and Other Intangible Assets (Goodwill) (Details)

v2.4.1.9
Goodwill and Other Intangible Assets (Goodwill) (Details) (USD $)
In Millions, unless otherwise specified
12 Months Ended
Dec. 31, 2014
Dec. 31, 2013
Dec. 31, 2012
Jan. 18, 2013
Goodwill [Line Items]        
Indefinite-Lived License Agreements $ 8,600us-gaap_IndefiniteLivedLicenseAgreements $ 8,600us-gaap_IndefiniteLivedLicenseAgreements    
Amortization of Intangible Assets 150us-gaap_AmortizationOfIntangibleAssets 115us-gaap_AmortizationOfIntangibleAssets 19us-gaap_AmortizationOfIntangibleAssets  
Finite-Lived Intangible Assets, Gross 1,616us-gaap_FiniteLivedIntangibleAssetsGross 1,587us-gaap_FiniteLivedIntangibleAssetsGross    
Finite-Lived Intangible Assets, Accumulated Amortization (520)us-gaap_FiniteLivedIntangibleAssetsAccumulatedAmortization (387)us-gaap_FiniteLivedIntangibleAssetsAccumulatedAmortization    
Finite-Lived Intangible Assets, Net 1,096us-gaap_FiniteLivedIntangibleAssetsNet 1,200us-gaap_FiniteLivedIntangibleAssetsNet    
Goodwill [Roll Forward]        
Goodwill, Beginning Balance 14,365us-gaap_Goodwill 200us-gaap_Goodwill    
Goodwill, Acquired During Period   14,165us-gaap_GoodwillAcquiredDuringPeriod    
Goodwill, Other Changes 2us-gaap_GoodwillOtherChanges      
Goodwill, Ending Balance 14,345us-gaap_Goodwill 14,365us-gaap_Goodwill 200us-gaap_Goodwill  
SIRIUS XM        
Goodwill [Line Items]        
Indefinite-Lived Trade Names 930us-gaap_IndefiniteLivedTradeNames
/ us-gaap_StatementBusinessSegmentsAxis
= lmca_SiriusXmMember
930us-gaap_IndefiniteLivedTradeNames
/ us-gaap_StatementBusinessSegmentsAxis
= lmca_SiriusXmMember
   
Goodwill [Roll Forward]        
Goodwill, Acquired During Period   14,165us-gaap_GoodwillAcquiredDuringPeriod
/ us-gaap_StatementBusinessSegmentsAxis
= lmca_SiriusXmMember
   
Goodwill, Ending Balance 14,165us-gaap_Goodwill
/ us-gaap_StatementBusinessSegmentsAxis
= lmca_SiriusXmMember
14,165us-gaap_Goodwill
/ us-gaap_StatementBusinessSegmentsAxis
= lmca_SiriusXmMember
   
ANLBC        
Goodwill [Line Items]        
Indefinite-Lived Franchise Rights 143us-gaap_IndefiniteLivedFranchiseRights
/ us-gaap_StatementBusinessSegmentsAxis
= lmca_AnlbcMember
143us-gaap_IndefiniteLivedFranchiseRights
/ us-gaap_StatementBusinessSegmentsAxis
= lmca_AnlbcMember
   
Licensing Agreements [Member]        
Goodwill [Line Items]        
Finite-Lived Intangible Asset, Useful Life 15 years      
Finite-Lived Intangible Assets, Gross 316us-gaap_FiniteLivedIntangibleAssetsGross
/ us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis
= us-gaap_LicensingAgreementsMember
316us-gaap_FiniteLivedIntangibleAssetsGross
/ us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis
= us-gaap_LicensingAgreementsMember
   
Finite-Lived Intangible Assets, Accumulated Amortization (52)us-gaap_FiniteLivedIntangibleAssetsAccumulatedAmortization
/ us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis
= us-gaap_LicensingAgreementsMember
(22)us-gaap_FiniteLivedIntangibleAssetsAccumulatedAmortization
/ us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis
= us-gaap_LicensingAgreementsMember
   
Finite-Lived Intangible Assets, Net 264us-gaap_FiniteLivedIntangibleAssetsNet
/ us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis
= us-gaap_LicensingAgreementsMember
294us-gaap_FiniteLivedIntangibleAssetsNet
/ us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis
= us-gaap_LicensingAgreementsMember
   
Customer Relationships [Member]        
Goodwill [Line Items]        
Finite-Lived Intangible Assets, Gross 838us-gaap_FiniteLivedIntangibleAssetsGross
/ us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis
= us-gaap_CustomerRelationshipsMember
838us-gaap_FiniteLivedIntangibleAssetsGross
/ us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis
= us-gaap_CustomerRelationshipsMember
   
Finite-Lived Intangible Assets, Accumulated Amortization (122)us-gaap_FiniteLivedIntangibleAssetsAccumulatedAmortization
/ us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis
= us-gaap_CustomerRelationshipsMember
(65)us-gaap_FiniteLivedIntangibleAssetsAccumulatedAmortization
/ us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis
= us-gaap_CustomerRelationshipsMember
   
Finite-Lived Intangible Assets, Net 716us-gaap_FiniteLivedIntangibleAssetsNet
/ us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis
= us-gaap_CustomerRelationshipsMember
773us-gaap_FiniteLivedIntangibleAssetsNet
/ us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis
= us-gaap_CustomerRelationshipsMember
   
Other Intangible Assets [Member]        
Goodwill [Line Items]        
Finite-Lived Intangible Assets, Gross 462us-gaap_FiniteLivedIntangibleAssetsGross
/ us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis
= us-gaap_OtherIntangibleAssetsMember
433us-gaap_FiniteLivedIntangibleAssetsGross
/ us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis
= us-gaap_OtherIntangibleAssetsMember
   
Finite-Lived Intangible Assets, Accumulated Amortization (346)us-gaap_FiniteLivedIntangibleAssetsAccumulatedAmortization
/ us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis
= us-gaap_OtherIntangibleAssetsMember
(300)us-gaap_FiniteLivedIntangibleAssetsAccumulatedAmortization
/ us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis
= us-gaap_OtherIntangibleAssetsMember
   
Finite-Lived Intangible Assets, Net 116us-gaap_FiniteLivedIntangibleAssetsNet
/ us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis
= us-gaap_OtherIntangibleAssetsMember
133us-gaap_FiniteLivedIntangibleAssetsNet
/ us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis
= us-gaap_OtherIntangibleAssetsMember
   
Other Intangible Assets [Member] | Corporate And Other        
Goodwill [Roll Forward]        
Goodwill, Beginning Balance 200us-gaap_Goodwill
/ us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis
= us-gaap_OtherIntangibleAssetsMember
/ us-gaap_StatementBusinessSegmentsAxis
= us-gaap_CorporateAndOtherMember
     
Goodwill, Other Changes 2us-gaap_GoodwillOtherChanges
/ us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis
= us-gaap_OtherIntangibleAssetsMember
/ us-gaap_StatementBusinessSegmentsAxis
= us-gaap_CorporateAndOtherMember
     
Goodwill, Ending Balance 180us-gaap_Goodwill
/ us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis
= us-gaap_OtherIntangibleAssetsMember
/ us-gaap_StatementBusinessSegmentsAxis
= us-gaap_CorporateAndOtherMember
  200us-gaap_Goodwill
/ us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis
= us-gaap_OtherIntangibleAssetsMember
/ us-gaap_StatementBusinessSegmentsAxis
= us-gaap_CorporateAndOtherMember
 
Minimum | Customer Relationships [Member]        
Goodwill [Line Items]        
Finite-Lived Intangible Asset, Useful Life 10 years      
Maximum | Customer Relationships [Member]        
Goodwill [Line Items]        
Finite-Lived Intangible Asset, Useful Life 15 years      
Liberty Broadband        
Goodwill [Roll Forward]        
Goodwill, Written off Related to Sale of Business Unit (46)us-gaap_GoodwillWrittenOffRelatedToSaleOfBusinessUnit
/ us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis
= lmca_LibertyBroadbandMember
     
Liberty Broadband | Other Intangible Assets [Member] | Corporate And Other        
Goodwill [Roll Forward]        
Goodwill, Written off Related to Sale of Business Unit (46)us-gaap_GoodwillWrittenOffRelatedToSaleOfBusinessUnit
/ us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis
= us-gaap_OtherIntangibleAssetsMember
/ us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis
= lmca_LibertyBroadbandMember
/ us-gaap_StatementBusinessSegmentsAxis
= us-gaap_CorporateAndOtherMember
     
SIRIUS XM        
Goodwill [Roll Forward]        
Goodwill, Beginning Balance       13,775us-gaap_Goodwill
/ us-gaap_BusinessAcquisitionAxis
= lmca_SiriusXmMember
Goodwill, Ending Balance       13,775us-gaap_Goodwill
/ us-gaap_BusinessAcquisitionAxis
= lmca_SiriusXmMember
TruePosition        
Goodwill [Roll Forward]        
Goodwill, Acquired During Period 24us-gaap_GoodwillAcquiredDuringPeriod
/ us-gaap_BusinessAcquisitionAxis
= lmca_TruepositionMember
     
TruePosition | Other Intangible Assets [Member] | Corporate And Other        
Goodwill [Roll Forward]        
Goodwill, Acquired During Period $ 24us-gaap_GoodwillAcquiredDuringPeriod
/ us-gaap_BusinessAcquisitionAxis
= lmca_TruepositionMember
/ us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis
= us-gaap_OtherIntangibleAssetsMember
/ us-gaap_StatementBusinessSegmentsAxis
= us-gaap_CorporateAndOtherMember