| 
           Long-Term Debt (Schedule of Financial Instruments Owned and Pledged as Collateral) (Details) ($1 billion margin loan due 2014, USD $) 
        In Millions, unless otherwise specified  | 
        
           Mar. 31, 2014 
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|---|---|
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           SIRIUS XM 
         | 
        |
| Debt Instrument [Line Items] | |
| Shares pledged as collateral under loan | 719.9 | 
| Share value | $ 2,304 | 
| 
           Live Nation 
         | 
        |
| Debt Instrument [Line Items] | |
| Shares pledged as collateral under loan | 8.1 | 
| Share value | 175 | 
| 
           Time Warner Inc 
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        |
| Debt Instrument [Line Items] | |
| Shares pledged as collateral under loan | 3.6 | 
| Share value | 237 | 
| 
           Viacom, Inc. 
         | 
        |
| Debt Instrument [Line Items] | |
| Shares pledged as collateral under loan | 3.5 | 
| Share value | 300 | 
| 
           Time Warner Cable Inc 
         | 
        |
| Debt Instrument [Line Items] | |
| Shares pledged as collateral under loan | 1.1 | 
| Share value | $ 153 | 
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- Definition 
          Shares pledged as collateral under loan No definition available. 
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- Details 
          
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- Definition 
          The fair value as of the balance sheet date of financial instruments and other positions owned by the entity and pledged to counterparties as collateral, including: (1) mortgages, mortgage-backed and asset backed securities; (2) US government and agency obligations; (3) state and municipal government obligations; (4) other sovereign government debt; (5) corporate obligations; (6) corporate equities; (7) principal investments; (8) derivative contracts; and (9) physical commodities. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
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