| Acquisitions Pro Forma (Details) - Pandora - SIRIUS XM Holdings - USD ($) $ in Millions | 1 Months Ended | 3 Months Ended | 
|---|---|---|
| Jan. 31, 2019 | Mar. 31, 2018 | |
| Acquisitions | ||
| Revenue | $ 2,128 | $ 1,839 | 
| Net earnings (loss) | (108) | 96 | 
| Net earnings (loss) attributable to Liberty stockholders | $ (145) | $ 51 | 
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- Definition BusinessAcquisitionProFormaNetIncomeLossAttributableToCommonShareholders No definition available. 
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. No definition available. 
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- Definition The pro forma net Income or Loss for the period as if the business combination or combinations had been completed at the beginning of a period. Reference 1: http://www.xbrl.org/2003/role/disclosureRef 
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- Definition The pro forma revenue for a period as if the business combination or combinations had been completed at the beginning of the period. Reference 1: http://www.xbrl.org/2003/role/disclosureRef 
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