CONSOLIDATED STATEMENTS OF STOCKHOLDERS’ EQUITY - USD ($) $ in Thousands	Total	Total Jacobs Stockholders’ Equity	Common Stock	Additional Paid-in Capital	Retained Earnings	Accumulated Other Comprehensive Income (Loss)	Noncontrolling Interests
Balance at the beginning of the period at Oct. 02, 2020	$ 5,855,667	$ 5,815,712	$ 129,748	$ 2,598,446	$ 4,020,575	$ (933,057)	$ 39,955
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net earnings	516,243	477,030			477,030		39,213
Foreign currency translation adjustments, net of deferred taxes	12,475	12,475				12,475
Pension and retiree medical plan liability, net of deferred taxes	104,165	104,165				104,165
Change in cash flow hedges, net of deferred taxes	21,975	21,975				21,975
Dividends	(109,616)	(109,616)			(109,616)
Noncontrolling interests - distributions and other	(44,372)						(44,372)
Stock based compensation	56,221	56,221		56,221
Redeemable Noncontrolling interests redemption value adjustment	(175,183)	(175,183)			(175,183)
Issuances of equity securities including shares withheld for taxes	12,210	12,210	871	20,345	(9,006)
Repurchases of equity securities	(274,948)	(274,948)	(1,726)	(85,000)	(188,222)
Balance at the end of the period at Oct. 01, 2021	5,974,837	5,940,041	128,893	2,590,012	4,015,578	(794,442)	34,796
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net earnings	680,827	644,039			644,039		36,788
Foreign currency translation adjustments, net of deferred taxes	(378,800)	(378,800)				(378,800)
Pension and retiree medical plan liability, net of deferred taxes	87,166	87,166				87,166
Change in cash flow hedges, net of deferred taxes	110,946	110,946				110,946
Dividends	(118,291)	(118,291)			(118,291)
Noncontrolling interests - distributions and other	(27,248)						(27,248)
Stock based compensation	53,383	53,383		53,383
Redeemable Noncontrolling interests redemption value adjustment	(27,657)	(27,657)			(27,657)
Repurchase and issuance of redeemable noncontrolling interests	2,618	2,618			2,618
Issuances of equity securities including shares withheld for taxes	28,537	28,537	973	39,537	(11,973)
Repurchases of equity securities	(281,926)	(281,926)	(2,473)	(923)	(278,530)
Balance at the end of the period at Sep. 30, 2022	6,104,392	6,060,056	127,393	2,682,009	4,225,784	(975,130)	44,336
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net earnings	698,042	665,777			665,777		32,265
Foreign currency translation adjustments, net of deferred taxes	150,103	150,103				150,103
Pension and retiree medical plan liability, net of deferred taxes	(18,297)	(18,297)				(18,297)
Change in cash flow hedges, net of deferred taxes	(14,630)	(14,630)				(14,630)
Dividends	(132,468)	(132,468)			(132,468)
Noncontrolling interests - distributions and other	(22,739)						(22,739)
Stock based compensation	74,337	74,337		74,337
Redeemable Noncontrolling interests redemption value adjustment	(10,770)	(10,770)			(10,770)
Repurchase and issuance of redeemable noncontrolling interests	14,293	14,293			14,293
Issuances of equity securities including shares withheld for taxes	23,533	23,533	910	28,181	(5,558)
Repurchases of equity securities	(265,714)	(265,714)	(2,326)	(49,202)	(214,186)
Balance at the end of the period at Sep. 29, 2023	$ 6,600,082	$ 6,546,220	$ 125,977	$ 2,735,325	$ 4,542,872	$ (857,954)	$ 53,862