Quarterly report pursuant to Section 13 or 15(d)

Basis of Presentation (Narrative) (Details)

v2.4.0.8
Basis of Presentation (Narrative) (Details) (USD $)
 3 Months Ended 0 Months Ended 1 Months Ended 3 Months Ended 6 Months Ended 0 Months Ended
Mar. 31, 2014
Mar. 31, 2013
Mar. 31, 2014
Lease Agreements
Oct. 09, 2013
SIRIUS XM
Jan. 18, 2013
SIRIUS XM
Dec. 31, 2013
SIRIUS XM
Mar. 31, 2013
SIRIUS XM
Mar. 31, 2014
SIRIUS XM
May 08, 2014
Subsequent Event
Liberty Broadband
Apr. 25, 2014
Subsequent Event
SIRIUS XM
Entity Information [Line Items]                    
Related Party Costs $ 2,000,000 $ 4,000,000                
Related Party Transaction, Amounts of Transaction     3,000,000              
Purchase of shares in equity method investee         50,000,000          
Convertible Preferred Stock, Shares Issued upon Conversion         1,293,509,076          
Subsidiary or Equity Method Investee, Cumulative Percentage Ownership after All Transactions             50.00%      
Business Combination, Step Acquisition, Equity Interest in Acquiree, Remeasurement Gain         7,500,000,000          
Stock Repurchased and Retired During Period, Shares           43,712,265   136,600,826    
Payments for Repurchase of Common Stock 0 140,000,000           500,000,000    
Number of Reportable Segments               3    
Stock Repurchased and Retired During Period, Value               3.6603   340,000,000
Share repurchases, discount from market price       1.50%            
Volume weighted average price period       10 days         20 days  
Volume weighted average share price, cap       4.18            
Volume weighted average share price, floor       $ 3.64            
Stock repurchased as a percentage of shares outstanding               2.00%    
Number of shares received in spin-off                 0.25  
Common Stock, Shares Subscribed but Unissued                 1  
Subscription right basis                 5  
Subscription right discount                 20.00%