| Investments In Affiliates Accounted For Using The Equity Method (Liberty Broadband's Consolidated Statement Of Operations) (Details) - Liberty Broadband - USD ($) $ in Millions | 3 Months Ended | 9 Months Ended | ||
|---|---|---|---|---|
| Sep. 30, 2017 | Sep. 30, 2016 | Sep. 30, 2017 | Sep. 30, 2016 | |
| Revenue | $ 3 | $ 21 | $ 10 | $ 27 | 
| Operating expenses, net | 9 | 14 | 29 | 41 | 
| Operating income (loss) | (6) | 7 | (19) | (14) | 
| Share of earnings (losses) of affiliates | (5) | 19 | 25 | 570 | 
| Realized and unrealized gains (losses) on financial instruments, net | 3 | 5 | 93 | |
| Gain (loss) on dilution of investment in affiliate | (4) | (16) | (42) | 760 | 
| Other income (expense), net | (5) | (4) | (14) | (5) | 
| Income tax benefit (expense) | 7 | (2) | 18 | (532) | 
| Net earnings (loss) | $ (10) | $ 4 | $ (27) | $ 872 | 
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- Definition The amount of net income (loss) reported by an equity method investment of the entity. No definition available. 
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- Definition The amount of operating expenses, net reported by an equity method investment of the entity. No definition available. 
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- Definition The amount of operating income (loss) reported by an equity method investment of the entity. No definition available. 
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- Definition The amount of other income (expense), net reported by an equity method investment of the entity. No definition available. 
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- Definition The amount of realized and unrealized gains (losses) on financial instruments, net reported by an equity method investment of the entity. No definition available. 
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- Definition The amount of share of earnings (losses) of affiliates reported by an equity method investment of the entity. No definition available. 
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- Definition Gain (loss) on dilution of investment in affiliate. No definition available. 
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- Definition The amount of net income (loss) reported by an equity method investment of the entity. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
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- Definition The amount of revenue from sale of goods and services reduced by sales returns, allowances, and discounts reported by an equity method investment of the entity. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
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