Inventories (Details) (USD $) In Millions, unless otherwise specified	Jun. 30, 2014	Dec. 31, 2013
Inventories Net
New vehicles	$ 1,738.0	$ 1,709.4
Used vehicles	643.4	589.2
Commercial vehicles	99.1	98.9
Parts, accessories and other	135.4	120.8
Total inventories	$ 2,615.9	$ 2,518.3