Note 1 - Summary of Significant Accounting Policies (Details Textual) $ in Millions	12 Months Ended
	Dec. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)	Dec. 31, 2014 USD ($)
Number of New Vehicle Brands	30
Number of Stores	154
Interest Costs Capitalized	$ 0.4	$ 0.5	$ 0.4
Number of Financial Institutions	18
Number of Manufacturer Affiliated Finance Companies	8
Long-term Debt, Percentage Bearing Variable Interest, Amount	$ 2,100.0
Standard and Extended Product Warranty Accrual	$ 0.4	$ 0.5
Number of Reportable Segments	3
Minimum [Member]
Long-term Debt, Percentage Bearing Variable Interest, Percentage Rate	2.02%
Maximum [Member]
Long-term Debt, Percentage Bearing Variable Interest, Percentage Rate	3.25%