| Disposals (Details) - GCI Liberty - Discontinued Operations Spinoff $ / shares in Units, $ in Millions | 3 Months Ended | 
|---|---|
| Mar. 31, 2018  USD ($)  $ / shares | |
| Liberty Ventures common stock | |
| Disposals | |
| Basic earnings (loss) from discontinued operations | $ / shares | $ 1.64 | 
| Diluted earnings (loss) from discontinued operations | $ / shares | $ 1.62 | 
| Evite | |
| Disposals | |
| Revenue | $ 3 | 
| Disposal group net earnings (loss) | (2) | 
| Liberty Broadband | |
| Disposals | |
| Earnings (loss) before income taxes | 187 | 
| Income tax (expense) benefit | (46) | 
| Maximum | LendingTree | |
| Disposals | |
| Disposal group net earnings (loss) | $ 1 | 
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- Definition Disposal Group Net Earnings (Loss) No definition available. 
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- Definition Amount before tax of income (loss) from operations classified as a discontinued operation. Excludes gain (loss) on disposal and provision for gain (loss) until its disposal. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef 
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- Definition Amount of tax expense (benefit) attributable to income (loss) from operations classified as a discontinued operation. Excludes tax expense (benefit) for gain (loss) on disposal and for provision for gain (loss) until disposal. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef 
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- Definition Amount of revenue attributable to disposal group, including, but not limited to, discontinued operation. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef 
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- Definition Per basic share amount, after tax, of income (loss) from the day-to-day business activities of the discontinued operation and gain (loss) from the disposal of the discontinued operation. Reference 1: http://www.xbrl.org/2003/role/disclosureRef 
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- Definition Per diluted share amount, after tax, of income (loss) from the day-to-day business activities of the discontinued operation and gain (loss) from the disposal of the discontinued operation. Reference 1: http://www.xbrl.org/2003/role/disclosureRef 
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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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