Quarterly report pursuant to Section 13 or 15(d)

Investments in Available-for-Sale Securities (Details)

v2.4.1.9
Investments in Available-for-Sale Securities (Details) (USD $)
Mar. 31, 2015
Dec. 31, 2014
Available-for-sale securities    
Investments in available-for-sale securities $ 355,202,000us-gaap_AvailableForSaleSecuritiesNoncurrent $ 360,762,000us-gaap_AvailableForSaleSecuritiesNoncurrent
Unrealized Holding Gains and Losses    
Gross unrealized holding gains 415,000us-gaap_AvailableForSaleEquitySecuritiesAccumulatedGrossUnrealizedGainBeforeTax 820,000us-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 742,000us-gaap_AvailableForSaleSecuritiesNoncurrent
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_OtherAggregatedInvestmentsMember
1,147,000us-gaap_AvailableForSaleSecuritiesNoncurrent
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_OtherAggregatedInvestmentsMember
Time Warner    
Available-for-sale securities    
Investments in available-for-sale securities $ 354,460,000us-gaap_AvailableForSaleSecuritiesNoncurrent
/ us-gaap_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis
= lbrda_TimeWarnerCableIncMember
$ 359,615,000us-gaap_AvailableForSaleSecuritiesNoncurrent
/ us-gaap_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis
= lbrda_TimeWarnerCableIncMember