| Information About Liberty's Operating Segments (Details) (USD $) In Millions, unless otherwise specified | 3 Months Ended | 12 Months Ended | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
| Dec. 31, 2014 | Sep. 30, 2014 | Jun. 30, 2014 | Mar. 31, 2014 | Dec. 31, 2013 | Sep. 30, 2013 | Jun. 30, 2013 | Mar. 31, 2013 | Dec. 31, 2014 | Dec. 31, 2013 | Dec. 31, 2012 | |
| Operating Activities And Reporting Information By Segment [Line Items] | |||||||||||
| Revenue, Net | $ 1,095 | $ 1,184 | $ 1,160 | $ 1,011 | $ 1,025 | $ 1,110 | $ 1,078 | $ 789 | $ 4,450 | $ 4,002 | $ 368 | 
| Adjusted OIBDA | 1,417 | 1,322 | 8 | ||||||||
| SIRIUS XM | |||||||||||
| Operating Activities And Reporting Information By Segment [Line Items] | |||||||||||
| Revenue, Net | 4,141 | 3,625 | |||||||||
| Adjusted OIBDA | 1,466 | 1,289 | |||||||||
| Corporate And Other | |||||||||||
| Operating Activities And Reporting Information By Segment [Line Items] | |||||||||||
| Revenue, Net | 309 | 377 | 368 | ||||||||
| Adjusted OIBDA | $ (49) | $ 33 | $ 8 | ||||||||