v2.4.0.6
Document and Entity Information
3 Months Ended
Mar. 29, 2013
May 07, 2013
Document and Entity Information    
Entity Registrant Name Willdan Group, Inc.  
Entity Central Index Key 0001370450  
Document Type 10-Q  
Document Period End Date Mar. 29, 2013  
Amendment Flag false  
Current Fiscal Year End Date --12-28  
Entity Current Reporting Status Yes  
Entity Filer Category Smaller Reporting Company  
Entity Common Stock, Shares Outstanding   7,352,772
Document Fiscal Year Focus 2013  
Document Fiscal Period Focus Q1