| Segment Information (Tables)
 | 9 Months Ended | 
      
        | Sep. 30, 2014 | 
      
        | Segment Information |  | 
      
        | Schedule of performance measures |  
		
			 
		 
			 
		 
			
				| 
						  | 
						  | 
						  | 
						  | 
						  | 
						  | 
						  | 
						  | 
						  | 
						  | 
						  |  
				| 
						  | 
						  | 
						  | 
						Three months ended  September 30,  | 
						  |  
				| 
						  | 
						  | 
						  | 
						2014 | 
						  | 
						2013 | 
						  |  
				| 
						  | 
						  | 
						  | 
						  | 
						  | 
						Adjusted | 
						  | 
						  | 
						  | 
						Adjusted | 
						  |  
				| 
						  | 
						  | 
						  | 
						Revenue | 
						  | 
						OIBDA | 
						  | 
						Revenue | 
						  | 
						OIBDA | 
						  |  
				| 
						  | 
						  | 
						  | 
						(amounts in thousands) | 
						  |  
				| 
						TruePosition | 
						     | 
						$ | 17,445 | 
						     | 3,033 | 
						     | 17,627 | 
						     | (1,048) | 
						  |  
				| 
						Charter | 
						  | 
						  | 2,287,000 | 
						  | 750,000 | 
						  | 2,118,000 | 
						  | 710,000 | 
						  |  
				| 
						Corporate and other | 
						  | 
						  | 
						  — | 
						  | 
						  — | 
						  | 
						  — | 
						  | 
						  — | 
						  |  
				| 
						  | 
						  | 
						  | 2,304,445 | 
						  | 753,033 | 
						  | 2,135,627 | 
						  | 708,952 | 
						  |  
				| 
						Eliminate equity method affiliate | 
						  | 
						  | (2,287,000) | 
						  | (750,000) | 
						  | (2,118,000) | 
						  | (710,000) | 
						  |  
				| 
						Combined Liberty Broadband | 
						  | 
						$ | 17,445 | 
						  | 3,033 | 
						  | 17,627 | 
						  | (1,048) | 
						  | 
			 
		 
			 
		 
			 
		 
			
				| 
						  | 
						  | 
						  | 
						  | 
						  | 
						  | 
						  | 
						  | 
						  | 
						  | 
						  |  
				| 
						  | 
						  | 
						Nine months ended September 30,  | 
						  |  
				| 
						  | 
						  | 
						2014 | 
						  | 
						2013 | 
						  |  
				| 
						  | 
						  | 
						  | 
						  | 
						  | 
						Adjusted | 
						  | 
						  | 
						  | 
						Adjusted | 
						  |  
				| 
						  | 
						  | 
						Revenue | 
						  | 
						OIBDA | 
						  | 
						Revenue | 
						  | 
						OIBDA | 
						  |  
				| 
						  | 
						  | 
						(amounts in thousands) | 
						  |  
				| 
						TruePosition | 
						     | 
						$ | 51,512 | 
						     | (5,252) | 
						     | 60,449 | 
						     | 2,592 | 
						  |  
				| 
						Charter | 
						  | 
						  | 6,748,000 | 
						  | 2,303,000 | 
						  | 6,007,000 | 
						  | 2,056,000 | 
						  |  
				| 
						Corporate and other | 
						  | 
						  | 
						— | 
						  | 
						— | 
						  | 
						— | 
						  | 
						— | 
						  |  
				| 
						  | 
						  | 
						  | 6,799,512 | 
						  | 2,297,748 | 
						  | 6,067,449 | 
						  | 2,058,592 | 
						  |  
				| 
						Eliminate equity method affiliate | 
						  | 
						  | (6,748,000) | 
						  | (2,303,000) | 
						  | (6,007,000) | 
						  | (2,056,000) | 
						  |  
				| 
						Combined Liberty Broadband | 
						  | 
						$ | 51,512 | 
						  | (5,252) | 
						  | 60,449 | 
						  | 2,592 | 
						  | 
			 
		   | 
      
        | Schedule of other information |  
		
			 
		 
			 
		 
			
				| 
						  | 
						  | 
						  | 
						  | 
						  | 
						  | 
						  | 
						  | 
						  |  
				| 
						  | 
						  | 
						September 30, 2014 | 
						  |  
				| 
						  | 
						  | 
						Total | 
						  | 
						Investments | 
						  | 
						Capital | 
						  |  
				| 
						  | 
						  | 
						assets | 
						  | 
						in affiliates | 
						  | 
						expenditures | 
						  |  
				| 
						  | 
						  | 
						(amounts in thousands) | 
						  |  
				| 
						TruePosition | 
						     | 
						$ | 175,302 | 
						     | 
						— | 
						     | 1,117 | 
						  |  
				| 
						Charter | 
						  | 
						  | 20,950,000 | 
						  | 
						— | 
						  | 1,678,000 | 
						  |  
				| 
						Corporate and other | 
						  | 
						  | 2,833,002 | 
						  | 2,373,627 | 
						  | 
						— | 
						  |  
				| 
						  | 
						  | 
						  | 23,958,304 | 
						  | 2,373,627 | 
						  | 1,679,117 | 
						  |  
				| 
						Eliminate equity method affiliate | 
						  | 
						  | (20,950,000) | 
						  | 
						  — | 
						  | (1,678,000) | 
						  |  
				| 
						Combined Liberty Broadband | 
						  | 
						$ | 3,008,304 | 
						  | 2,373,627 | 
						  | 1,117 | 
						  | 
			 
		   | 
      
        | Schedule of reconciliation of segment Adjusted OIBDA to earnings (loss) before income taxes |  
		
			 
		 
			 
		 
			
				| 
						  | 
						  | 
						  | 
						  | 
						  | 
						  | 
						  | 
						  | 
						  | 
						  | 
						  |  
				| 
						  | 
						  | 
						Three months | 
						  | 
						Nine months | 
						  |  
				| 
						  | 
						  | 
						ended September 30,  | 
						  | 
						ended September 30,  | 
						  |  
				| 
						  | 
						  | 
						2014 | 
						  | 
						2013 | 
						  | 
						2014 | 
						     | 
						2013 | 
						  |  
				| 
						  | 
						  | 
						  | 
						(amounts in thousands) | 
						  |  
				| 
						Combined segment Adjusted OIBDA | 
						     | 
						$ | 3,033 | 
						     | (1,048) | 
						     | (5,252) | 
						     | 2,592 | 
						  |  
				| 
						Stock-based compensation | 
						  | 
						  | (190) | 
						  | (367) | 
						  | (735) | 
						  | (1,082) | 
						  |  
				| 
						Depreciation and amortization | 
						  | 
						  | (2,479) | 
						  | (1,065) | 
						  | (6,583) | 
						  | (3,374) | 
						  |  
				| 
						Gain on legal settlement | 
						  | 
						  | 6,000 | 
						  | 
						  — | 
						  | 6,000 | 
						  | 
						  — | 
						  |  
				| 
						Dividend and interest income | 
						  | 
						  | 1,228 | 
						  | 1,766 | 
						  | 4,231 | 
						  | 5,203 | 
						  |  
				| 
						Share of earnings (loss) of affiliates, net | 
						  | 
						  | (34,542) | 
						  | (38,400) | 
						  | (95,968) | 
						  | (65,666) | 
						  |  
				| 
						Realized and unrealized gains (losses) on financial instruments, net | 
						  | 
						  | (12,532) | 
						  | 9,167 | 
						  | 23,745 | 
						  | 68,029 | 
						  |  
				| 
						Gain (loss) on dilution of investment in affiliate | 
						  | 
						  | (10,953) | 
						  | (52,163) | 
						  | (61,162) | 
						  | (55,219) | 
						  |  
				| 
						Other, net | 
						  | 
						  | 8 | 
						  | (8) | 
						  | (60) | 
						  | (45) | 
						  |  
				| 
						Earnings (loss) before income taxes | 
						  | 
						$ | (50,427) | 
						  | (82,118) | 
						  | (135,784) | 
						  | (49,562) | 
						  | 
			 
		   |