Description of Business and Summary of Significant Accounting Policies (Organization and Business, Inventory) (Details)	12 Months Ended
	Dec. 31, 2021 store brand franchises
Product Information [Line Items]
Owned and operated new vehicle franchises | franchises	339
Number of brands | brand	33
Percentage of new vehicle sales from core brands (percent)	90.00%
Dealerships [Member]
Product Information [Line Items]
Number of stores	247
Collision Center [Member]
Product Information [Line Items]
Number of stores	57
AutoNation USA Stores [Member]
Product Information [Line Items]
Number of stores	9
Automotive Auction Operations [Member]
Product Information [Line Items]
Number of stores	4
Parts Distribution Centers [Member]
Product Information [Line Items]
Number of stores	3