Annual report pursuant to Section 13 and 15(d)

Investments in Available-for-Sale Securities (Details)

v2.4.1.9
Investments in Available-for-Sale Securities (Details) (USD $)
Dec. 31, 2014
Dec. 31, 2013
Available-for-sale securities    
Investments in available-for-sale securities $ 360,762,000us-gaap_AvailableForSaleSecuritiesNoncurrent $ 326,700,000us-gaap_AvailableForSaleSecuritiesNoncurrent
Unrealized Holding Gains and Losses    
Gross unrealized holding gains 982,000us-gaap_AvailableForSaleEquitySecuritiesAccumulatedGrossUnrealizedGainBeforeTax 5,900,000us-gaap_AvailableForSaleEquitySecuritiesAccumulatedGrossUnrealizedGainBeforeTax
Gross unrealized holding losses 0us-gaap_AvailableForSaleEquitySecuritiesAccumulatedGrossUnrealizedLossBeforeTax 0us-gaap_AvailableForSaleEquitySecuritiesAccumulatedGrossUnrealizedLossBeforeTax
Other equity securities    
Available-for-sale securities    
Investments in available-for-sale securities 1,147,000us-gaap_AvailableForSaleSecuritiesNoncurrent
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_OtherAggregatedInvestmentsMember
6,248,000us-gaap_AvailableForSaleSecuritiesNoncurrent
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_OtherAggregatedInvestmentsMember
Time Warner    
Available-for-sale securities    
Investments in available-for-sale securities $ 359,615,000us-gaap_AvailableForSaleSecuritiesNoncurrent
/ us-gaap_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis
= lbrda_TimeWarnerCableIncMember
$ 320,452,000us-gaap_AvailableForSaleSecuritiesNoncurrent
/ us-gaap_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis
= lbrda_TimeWarnerCableIncMember