Consolidated Statements of Earnings - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Jun. 30, 2017	Jul. 01, 2016	Jun. 30, 2017	Jul. 01, 2016
Income Statement [Abstract]
Revenues	$ 2,514,751	$ 2,693,873	$ 7,368,922	$ 8,323,570
Costs and Expenses:
Direct cost of contracts	(2,055,386)	(2,242,424)	(6,070,961)	(6,987,431)
Selling, general and administrative expenses	(330,890)	(341,893)	(1,012,685)	(1,080,352)
Operating Profit	128,475	109,556	285,276	255,787
Other Income (Expense):
Interest income	2,123	624	5,697	5,108
Interest expense	(4,054)	(4,572)	(11,327)	(10,315)
Miscellaneous income (expense), net	852	(2,801)	(5,879)	470
Total other (expense) income, net	(1,079)	(6,749)	(11,509)	(4,737)
Earnings Before Taxes	127,396	102,807	273,767	251,050
Income Tax Expense	(38,767)	(31,870)	(79,820)	(66,418)
Net Earnings of the Group	88,629	70,937	193,947	184,632
Net Earnings (Losses) Attributable to Noncontrolling Interests	403	(1,882)	5,639	(3,813)
Net Earnings Attributable to Jacobs	$ 89,032	$ 69,055	$ 199,586	$ 180,819
Net Earnings Per Share:
Basic (in dollars per share)	$ 0.74	$ 0.58	$ 1.65	$ 1.50
Diluted (in dollars per share)	$ 0.74	$ 0.57	$ 1.64	$ 1.49