PA Consulting Redeemable Noncontrolling Interests - Schedule of Change in Redeemable Noncontrolling Interest (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Mar. 29, 2024	Mar. 31, 2023	Mar. 29, 2024	Mar. 31, 2023
Stockholders' Equity Attributable to Noncontrolling Interest [Roll Forward]
Redeemable noncontrolling interest, beginning balance			$ 53,862
Attribution of Preferred Dividend to Common Shareholders	$ (9,568)	$ (8,910)	(14,081)	$ (10,783)
Redeemable noncontrolling interest, ending balance	54,348		54,348
PA Consulting Employees
Stockholders' Equity Attributable to Noncontrolling Interest [Roll Forward]
Redeemable noncontrolling interest, beginning balance			632,979
Accrued Preferred Dividend to Preference Shareholders			39,710
Attribution of Preferred Dividend to Common Shareholders			(39,710)
Net earnings attributable to redeemable noncontrolling interests to Common Shareholders			6,700
Redeemable Noncontrolling interests redemption value adjustment			96,562
Repurchase of redeemable noncontrolling interests			(26,258)
Cumulative translation adjustment and other			15,847
Redeemable noncontrolling interest, ending balance	$ 725,830		$ 725,830