Other Financial Information - Schedule of Components of Receivables and Contract Assets (Details) - USD ($) $ in Thousands	Sep. 26, 2025	Sep. 27, 2024
Other Financial Information [Abstract]
Amounts billed, net	$ 1,386,253	$ 1,278,980
Unbilled receivables and other	1,115,286	1,132,980
Contract assets	487,528	433,492
Total receivables and contract assets, net	$ 2,989,067	$ 2,845,452

Other Financial Information [Abstract]

No definition available.

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- Definition

Amounts due for billed services rendered or to be rendered, actions taken or to be taken, or a promise to refrain from taking certain actions in accordance with the terms of a legally binding agreement between the Company and, at a minimum, one other party. An example would be amounts billed to customers under contracts or programs but not paid as of the balance sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 912
-SubTopic 310
-Name Accounting Standards Codification
-Section 45
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478345/912-310-45-2

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- Definition

Carrying amount of assets as of the balance sheet date pertaining to amounts paid by the insured (including a ceding company) under insurance or reinsurance contracts for which insurance risk is not transferred.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 340
-SubTopic 30
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483081/340-30-45-1

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 340
-SubTopic 30
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483054/340-30-50-1

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- Definition

The total amount due to the entity within one year of the balance sheet date (or one operating cycle, if longer) from outside sources, including trade accounts receivable, notes and loans receivable, as well as any other types of receivables, net of allowances established for the purpose of reducing such receivables to an amount that approximates their net realizable value.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 852
-SubTopic 10
-Name Accounting Standards Codification
-Section 55
-Paragraph 10
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481372/852-10-55-10

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- Definition

Unbilled amounts due for services rendered or to be rendered, actions taken or to be taken, or a promise to refrain from taking certain actions in accordance with the terms of a legally binding agreement between the entity and, at a minimum, one other party. An example would be amounts associated with contracts or programs where the recognized revenue for performance thereunder exceeds the amounts billed under the terms thereof as of the date of the balance sheet.

+ References

+ Details

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