v3.10.0.1
Derivative Instruments (Realized and Unrealized Gains (Losses) on Derivatives) (Schedule and Footnotes) (Details) - USD ($)
$ in Millions
3 Months Ended 6 Months Ended
Jun. 30, 2018
Jun. 30, 2017
Jun. 30, 2018
Jun. 30, 2017
Derivative [Line Items]        
Gain (loss) on derivative instruments, net $ 675.5 $ (351.7) $ 464.2 $ (596.1)
Cross-currency and interest rate derivative contracts        
Derivative [Line Items]        
Gain (loss) on derivative instruments, net 870.1 (502.3) 508.2 (659.1)
Equity-related derivative instruments:        
Derivative [Line Items]        
Gain (loss) on derivative instruments, net (202.4) 163.5 (57.2) 81.5
ITV Collar        
Derivative [Line Items]        
Gain (loss) on derivative instruments, net (183.6) 163.4 (60.0) 110.2
Lionsgate Forward        
Derivative [Line Items]        
Gain (loss) on derivative instruments, net 3.4 (2.5) 12.4 (2.0)
Sumitomo Collar        
Derivative [Line Items]        
Gain (loss) on derivative instruments, net (23.2) 2.2 (11.8) (21.3)
Other        
Derivative [Line Items]        
Gain (loss) on derivative instruments, net 1.0 0.4 2.2 (5.4)
Foreign currency forward and option contracts        
Derivative [Line Items]        
Gain (loss) on derivative instruments, net 8.3 (12.9) 13.9 (19.0)
Other        
Derivative [Line Items]        
Gain (loss) on derivative instruments, net $ (0.5) $ 0.0 $ (0.7) $ 0.5