XML 24 R78.htm IDEA: XBRL DOCUMENT
v2.3.0.15

Savings And Deferred Compensation Plans (Savings Plans) (Details) (USD $) In Thousands | 12 Months Ended
--- | ---
Sep. 30, 2011 | Oct. 01, 2010 | Oct. 02, 2009
Savings And Deferred Compensation Plans |  |  |
Savings plans contributions | $ 61,065 | $ 57,346 | $ 54,957

X
- Definition Defined Contribution Plan Savings Plans Contributions + Details
Name: | jec_DefinedContributionPlanSavingsPlansContributions
Namespace Prefix: | jec
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Savings And Deferred Compensation Plans [Abstract] + Details
Name: | jec_SavingsAndDeferredCompensationPlansAbstract
Namespace Prefix: | jec
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration