Long-Term Debt (Restrictions And Covenants) (Details) (USD $) In Millions, unless otherwise specified	9 Months Ended
	Sep. 30, 2011
The maximum of amount of letters of credit excluded from the leverage ratio calculation	$ 150.0
Debt instrument, covenant description	Our amended credit agreement, the indenture for our 6.75% Senior Notes due 2018, our vehicle floorplan facilities, and our mortgage facility contain customary financial and operating covenants that place restrictions on us, including our ability to incur additional indebtedness or prepay existing indebtedness, to create liens or other encumbrances, to sell (or otherwise dispose of) assets, and to merge or consolidate with other entities. Under our amended credit agreement we are required to remain in compliance with a maximum leverage ratio and maximum capitalization ratio. The leverage ratio is a contractually defined amount principally reflecting non-vehicle debt divided by a contractually defined measure of earnings with certain adjustments. The capitalization ratio is a contractually defined amount principally reflecting vehicle floorplan payable and non-vehicle debt divided by our total capitalization including vehicle floorplan payable. Under the amended credit agreement, the maximum capitalization ratio is 60% and the maximum leverage ratio is 3.25x. In calculating our leverage ratio, we are not required to include letters of credit in the definition of debt (except to the extent of letters of credit in excess of $150.0 million), and, in calculating our capitalization ratio, we are permitted to add back to shareholders’ equity all goodwill, franchise rights, and long-lived asset impairment charges subsequent to 2007. The indenture for our 6.75% Senior Notes due 2018 contains certain limited covenants, including limitations on liens and sale and leaseback transactions, but does not contain a restricted payments covenant or a debt incurrence restriction. Our mortgage facility contains covenants regarding maximum cash flow leverage and minimum interest coverage. Our failure to comply with the covenants contained in our debt agreements could permit acceleration of all of our indebtedness. Our debt agreements have cross-default provisions that trigger a default in the event of an uncured default under other material indebtedness of AutoNation.
Amended Credit Agreement Maximum Ratio Requirement [Member]
Leverage ratio	3.25
Capitalization ratio	60.00%