v3.10.0.1
Share-based Compensation Share-Based Compensation Expense) (Details) - USD ($)
$ in Millions
3 Months Ended 6 Months Ended
Jun. 30, 2018
Jun. 30, 2017
Jun. 30, 2018
Jun. 30, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Share-based compensation expense $ 45.5 $ 51.4 $ 88.2 $ 80.3
Other operating expense        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Share-based compensation expense 0.0 0.9 1.0 1.9
SG&A expense        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Share-based compensation expense 45.5 50.5 87.2 78.4
Liberty Global        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Share-based compensation expense 45.7 43.7 83.5 66.1
Performance-based incentive awards | Liberty Global        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Share-based compensation expense 8.0 19.1 16.7 19.8
Non-performance based share-based incentive awards | Liberty Global        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Share-based compensation expense 24.3 24.6 46.3 46.3
Other        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Share-based compensation expense (0.2) 7.7 4.7 14.2
Other | Liberty Global        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Share-based compensation expense $ 13.4 $ 0.0 $ 20.5 $ 0.0