v2.4.0.8
Document And Entity Information
9 Months Ended
Sep. 30, 2015
Nov. 01, 2015
Common Class B [Member]
Nov. 01, 2015
Common Class A [Member]
Entity Registrant Name RUSH ENTERPRISES INC \TX\    
Entity Central Index Key 0001012019    
Trading Symbol rusha    
Current Fiscal Year End Date --12-31    
Entity Filer Category Large Accelerated Filer    
Entity Current Reporting Status Yes    
Entity Voluntary Filers No    
Entity Well-known Seasoned Issuer Yes    
Entity Common Stock, Shares Outstanding (in shares)   10,093,305 30,277,484
Document Type 10-Q    
Document Period End Date Sep. 30, 2015    
Document Fiscal Year Focus 2015    
Document Fiscal Period Focus Q3    
Amendment Flag false