v2.4.0.6
Document and Entity Information (USD $)
12 Months Ended
Dec. 31, 2011
Jun. 30, 2011
Mar. 08, 2012
Common Class A
Mar. 08, 2012
Common Class B
Entity Registrant Name RUSH ENTERPRISES INC \TX\      
Entity Central Index Key 0001012019      
Document Type 10-K      
Document Period End Date Dec. 31, 2011      
Amendment Flag false      
Document Fiscal Year Focus 2011      
Document Fiscal Period Focus FY      
Current Fiscal Year End Date --12-31      
Entity Well-known Seasoned Issuer No      
Entity Voluntary Filers No      
Entity Current Reporting Status Yes      
Entity Filer Category Accelerated Filer      
Entity Public Float   $ 618,179,524    
Entity Common Stock, Shares Outstanding     27,713,888 10,779,674