XML 50 R39.htm IDEA: XBRL DOCUMENT v3.20.2
Inventory And Vehicle Floorplan Payable (Components Of Inventory) (Details) - USD ($)
$ in Millions
Jun. 30, 2020
Dec. 31, 2019
Inventory [Line Items]    
Inventory $ 2,432.3 $ 3,305.8
New Vehicle [Member]    
Inventory [Line Items]    
Inventory 1,716.7 2,490.8
Used Vehicle [Member]    
Inventory [Line Items]    
Inventory 493.9 570.0
Parts and Service [Member]    
Inventory [Line Items]    
Inventory $ 221.7 $ 245.0