Quarterly report pursuant to Section 13 or 15(d)

Assets and Liabilities Measured at Fair Value (Schedule of Realized and Unrealized Gains (Losses)) (Details)

v3.8.0.1
Assets and Liabilities Measured at Fair Value (Schedule of Realized and Unrealized Gains (Losses)) (Details) - USD ($)
$ in Thousands
3 Months Ended
Mar. 31, 2018
Mar. 31, 2017
Gain (Loss) on Investments [Line Items]    
Realized and unrealized gains (losses) on financial instruments, net $ (71,481) $ 737,552
Indemnification obligation    
Gain (Loss) on Investments [Line Items]    
Realized and unrealized gains (losses) on financial instruments, net 28,717 0
Variable forward    
Gain (Loss) on Investments [Line Items]    
Realized and unrealized gains (losses) on financial instruments, net 8,743 0
Investment in Liberty Broadband    
Gain (Loss) on Investments [Line Items]    
Realized and unrealized gains (losses) on financial instruments, net 22,621 526,267
Equity securities    
Gain (Loss) on Investments [Line Items]    
Realized and unrealized gains (losses) on financial instruments, net $ (131,562) $ 211,285