XML 77 R1.htm IDEA: XBRL DOCUMENT v2.4.1.9
Document and Entity Information (USD $)
In Billions, except Share data, unless otherwise specified
 12 Months Ended
Dec. 31, 2014
Feb. 09, 2015
Jun. 30, 2014
Document Information [Line Items]      
Document Type 10-K    
Amendment Flag false    
Document Period End Date Dec. 31, 2014    
Document Fiscal Period Focus FY    
Document Fiscal Year Focus 2014    
Trading Symbol AN    
Entity Registrant Name AUTONATION, INC.    
Entity Central Index Key 0000350698    
Current Fiscal Year End Date --12-31    
Entity Filer Category Large Accelerated Filer    
Entity Common Stock, Shares Outstanding   113,578,092dei_EntityCommonStockSharesOutstanding  
Entity Well-known Seasoned Issuer Yes    
Entity Voluntary Filers No    
Entity Current Reporting Status Yes    
Entity Public Float     $ 4.4dei_EntityPublicFloat