Interim Financial Information (Details Textual) $ in Millions	3 Months Ended	12 Months Ended
	Jun. 30, 2016 dealerships town states	Dec. 31, 2015 USD ($)
Business And Organization [Line Items]
Number of Domestic Regions	2
Number of International Regions	2
Number of Reportable Segments	3
Variable Interest Entity, Ownership Percentage	8.00%
Deferred income taxes | $		$ 14.1
Debt Issuance Costs, Current Assets | $		0.5
Debt Issuance Costs, Long-term Assets | $		$ 3.6
East [Member]
Business And Organization [Line Items]
Number of Dealerships	37
West [Member]
Business And Organization [Line Items]
Number of Dealerships	77
U.S. [Member]
Business And Organization [Line Items]
Number of States in which Entity Operates | states	14
U.K. [Member]
Business And Organization [Line Items]
Number of Towns in which Entity Operates | town	19
Number of Dealerships	29
Brazil [Member]
Business And Organization [Line Items]
Number of States in which Entity Operates | states	4
Number of Dealerships	18