PA Consulting Redeemable Noncontrolling Interests - Schedule of Change in Redeemable Noncontrolling Interest (Details) - USD ($) $ in Thousands	12 Months Ended
Sep. 26, 2025	Sep. 27, 2024	Sep. 29, 2023
Stockholders' Equity Attributable to Noncontrolling Interest [Roll Forward]
Redeemable noncontrolling interest, beginning balance	$ 17,836
Attribution of Preferred Dividend to Common Shareholders	(14,181)	$ (21,202)	$ (22,739)
Redeemable noncontrolling interest, ending balance	7,098	17,836
PA Consulting Employees
Stockholders' Equity Attributable to Noncontrolling Interest [Roll Forward]
Redeemable noncontrolling interest, beginning balance	820,182	632,979
Accrued Preferred Dividend to Preference Shareholders	81,713	73,033
Attribution of Preferred Dividend to Common Shareholders	(81,713)	(73,033)
Net earnings attributable to redeemable noncontrolling interest to Common Shareholders	11,177	14,999
Redeemable Noncontrolling interests redemption value adjustment	199,763	171,142
Repurchase of redeemable noncontrolling interests	(13,999)	(62,867)
Issuance of redeemable noncontrolling interests	0	22,586
Cumulative translation adjustment and other	1,571	41,343
Redeemable noncontrolling interest, ending balance	$ 1,018,694	$ 820,182	$ 632,979

Noncontrolling Interest, Increase from Cumulative Translation Adjustment and Other

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Amount of equity (deficit) attributable to noncontrolling interest. Excludes temporary equity.

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Decrease in noncontrolling interest balance from payment of dividends or other distributions by the non-wholly owned subsidiary or partially owned entity, included in the consolidation of the parent entity, to the noncontrolling interest holders.

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