| Schedule of Quarterly Financial Information |  
		
			
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						1st | 
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						2nd | 
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						3rd | 
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						4th | 
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						Quarter | 
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						Quarter | 
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						Quarter | 
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						Quarter | 
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						amounts in thousands | 
						  |  
				| 
						2017:  | 
						     | 
						  | 
						  | 
						     | 
						  | 
						     | 
						  | 
						     | 
						  | 
						  |  
				| 
						Revenue | 
						  | 
						$ | 
						 3,140 | 
						  | 
						 3,073 | 
						  | 
						 3,430 | 
						  | 
						 3,449 | 
						  |  
				| 
						Operating income (loss) | 
						  | 
						$ | 
						 (6,362) | 
						  | 
						 (7,333) | 
						  | 
						 (5,787) | 
						  | 
						 (5,996) | 
						  |  
				| 
						Net earnings (loss) attributable to Liberty Broadband Corporation Series A, Series B and Series C stockholders | 
						  | 
						$ | 
						 (14,445) | 
						  | 
						 (2,977) | 
						  | 
						 (9,864) | 
						  | 
						 2,060,953 | 
						  |  
				| 
						Basic earnings (loss) attributable to Liberty Broadband Corporation Series A, Series B and Series C stockholders per common share | 
						  | 
						$ | 
						 (0.08) | 
						  | 
						 (0.02) | 
						  | 
						 (0.05) | 
						  | 
						 11.37 | 
						  |  
				| 
						Diluted earnings (loss) attributable to Liberty Broadband Corporation Series A, Series B and Series C stockholders per common share | 
						  | 
						$ | 
						 (0.08) | 
						  | 
						 (0.02) | 
						  | 
						 (0.05) | 
						  | 
						 11.28 | 
						  | 
			 
		 
			 
		 
			 
		 
			 
		 
			 
		 
			
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						  | 
						  | 
						1st | 
						  | 
						2nd | 
						  | 
						3rd | 
						  | 
						4th | 
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				| 
						  | 
						  | 
						Quarter | 
						  | 
						Quarter | 
						  | 
						Quarter | 
						  | 
						Quarter | 
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				| 
						  | 
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						amounts in thousands | 
						  |  
				| 
						2016: | 
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						  | 
						     | 
						  | 
						     | 
						  | 
						     | 
						  | 
						  |  
				| 
						Revenue | 
						  | 
						$ | 
						 3,831 | 
						  | 
						 2,966 | 
						  | 
						 20,616 | 
						  | 
						 3,173 | 
						  |  
				| 
						Operating income (loss) | 
						  | 
						$ | 
						 (9,340) | 
						  | 
						 (10,737) | 
						  | 
						 6,624 | 
						  | 
						 (7,707) | 
						  |  
				| 
						Net earnings (loss) attributable to Liberty Broadband Corporation Series A, Series B and Series C stockholders | 
						  | 
						$ | 
						 (22,241) | 
						  | 
						 890,154 | 
						  | 
						 3,789 | 
						  | 
						 45,601 | 
						  |  
				| 
						Basic earnings (loss) attributable to Liberty Broadband Corporation Series A, Series B and Series C stockholders per common share | 
						  | 
						$ | 
						 (0.22) | 
						  | 
						 6.31 | 
						  | 
						 0.02 | 
						  | 
						 0.25 | 
						  |  
				| 
						Diluted earnings (loss) attributable to Liberty Broadband Corporation Series A, Series B and Series C stockholders per common share | 
						  | 
						$ | 
						 (0.22) | 
						  | 
						 6.28 | 
						  | 
						 0.02 | 
						  | 
						 0.25 | 
						  | 
			 
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