Annual report pursuant to Section 13 and 15(d)

Inventories and Related Notes Payable - Floor Plan - Additional Information (Details)

v3.10.0.1
Inventories and Related Notes Payable - Floor Plan - Additional Information (Details) - USD ($)
$ in Millions
12 Months Ended
Dec. 31, 2018
Dec. 31, 2017
Dec. 31, 2016
Inventory Disclosure [Abstract]      
Average interest rate for new vehicle floor plan facilities 3.10% 2.37% 1.85%
Amount recognized for floor plan assistance $ 42.2 $ 45.3 $ 45.0
Average interest rate for used vehicle floor plan facilities 2.98% 2.61% 1.78%