CONSOLIDATED STATEMENTS OF STOCKHOLDERS’ EQUITY (Parenthetical) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Jun. 26, 2026	Jun. 27, 2025	Jun. 26, 2026	Jun. 27, 2025
Statement of Stockholders' Equity [Abstract]
Foreign currency translation adjustments	$ 0	$ (4,558)	$ 0	$ (4,558)
Pension and retiree medical plan liability, deferred taxes	(3,116)	762	(983)	2,594
Derivative gains (losses), deferred tax expense (benefit)	(160)	$ (856)	(748)	$ (1,107)
Redemption of redeemable noncontrolling interests relating to the PA Consulting Transaction	$ (315)		$ (35,696)

Amount of tax expense (benefit), after reclassification adjustments of gain (loss) on foreign currency translation adjustments, foreign currency transactions designated and effective as economic hedges of a net investment in a foreign entity and intra-entity foreign currency transactions that are of a long-term-investment nature.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Section 45
-Paragraph 10A
-Subparagraph (a)
-SubTopic 10
-Topic 220
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482790/220-10-45-10A

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Section 45
-Paragraph 12
-SubTopic 10
-Topic 220
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482790/220-10-45-12

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 830
-SubTopic 20
-Name Accounting Standards Codification
-Section 45
-Paragraph 5
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481956/830-20-45-5

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 830
-SubTopic 30
-Name Accounting Standards Codification
-Section 45
-Paragraph 21
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481694/830-30-45-21

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Balance Type:	debit
Period Type:	duration