XML 26 R1.htm IDEA: XBRL DOCUMENT v2.4.0.6
Document And Entity Information
3 Months Ended
Dec. 30, 2011
Jan. 20, 2012
Entity Information [Line Items]    
Document Type 10-Q  
Amendment Flag false  
Document Period End Date Dec. 30, 2011  
Document Fiscal Year Focus 2012  
Document Fiscal Period Focus Q1  
Trading Symbol jec  
Entity Registrant Name JACOBS ENGINEERING GROUP INC /DE/  
Entity Central Index Key 0000052988  
Current Fiscal Year End Date --09-28  
Entity Filer Category Large Accelerated Filer  
Entity Common Stock, Shares Outstanding   128,493,619