Annual report pursuant to Section 13 and 15(d)

Stockholders' Equity (Details)

v2.4.1.9
Stockholders' Equity (Details) (USD $)
 0 Months Ended 12 Months Ended 0 Months Ended
Nov. 04, 2014
Oct. 29, 2014
Dec. 31, 2014
Jan. 09, 2015
Dec. 10, 2014
Dec. 31, 2013
Broadband Spin-Off Distribution Ratio   0.25lbrda_Lbrda_spinOffDistributionRatio        
Shares issued during period 85,761,332us-gaap_StockIssuedDuringPeriodSharesNewIssues   85,761,332us-gaap_StockIssuedDuringPeriodSharesNewIssues      
Preferred shares issued     0us-gaap_PreferredStockSharesIssued     0us-gaap_PreferredStockSharesIssued
Class A common stock            
Broadband Spin-Off Distribution Ratio   0.25lbrda_Lbrda_spinOffDistributionRatio
/ us-gaap_StatementClassOfStockAxis
= us-gaap_CommonClassAMember 		       
Number of votes     1lbrda_NumberOfVotes
/ us-gaap_StatementClassOfStockAxis
= us-gaap_CommonClassAMember 		     
Shares reserved for future issuance upon exercise of stock options     807,000us-gaap_CommonStockCapitalSharesReservedForFutureIssuance
/ us-gaap_StatementClassOfStockAxis
= us-gaap_CommonClassAMember 		     
Class B common stock            
Number of votes     10lbrda_NumberOfVotes
/ us-gaap_StatementClassOfStockAxis
= us-gaap_CommonClassBMember 		     
Shares received in exchange     1lbrda_CommonStockSharesReceivedInExchangeForOneShareOfSeriesB
/ us-gaap_StatementClassOfStockAxis
= us-gaap_CommonClassBMember 		     
Class C common stock            
Subscription rights distribution ratio         0.20lbrda_SubscriptionRightsDistributionRatio
/ us-gaap_StatementClassOfStockAxis
= us-gaap_CommonClassCMember 		 
Shares issued during period       17,277,224us-gaap_StockIssuedDuringPeriodSharesNewIssues
/ us-gaap_StatementClassOfStockAxis
= us-gaap_CommonClassCMember 		   
Purchase price (in dollars per share)         $ 40.36us-gaap_SharePrice
/ us-gaap_StatementClassOfStockAxis
= us-gaap_CommonClassCMember 		 
Discount percentage for holders to acquire shares enabled by subscription rights         20.00%lbrda_SubscriptionRightsDiscountToMarketPercentage
/ us-gaap_StatementClassOfStockAxis
= us-gaap_CommonClassCMember 		 
Number of trading days of volume weighted average trading price used for calculating discount for holders to acquire shares enabled by subscription rights         20 days  
Number of votes     0lbrda_NumberOfVotes
/ us-gaap_StatementClassOfStockAxis
= us-gaap_CommonClassCMember 		     
Shares reserved for future issuance upon exercise of stock options     3,100,000us-gaap_CommonStockCapitalSharesReservedForFutureIssuance
/ us-gaap_StatementClassOfStockAxis
= us-gaap_CommonClassCMember 		     
Shares reserved for issuance pursuant to the rights offering     17,300,000lbrda_CommonStockCapitalSharesReservedForIssuanceOfRightOffering
/ us-gaap_StatementClassOfStockAxis
= us-gaap_CommonClassCMember