Receivables (Schedule of Receivables) (Details) - USD ($) $ in Thousands	6 Months Ended	12 Months Ended
Mar. 28, 2020	Sep. 28, 2019
Receivables [Abstract]
Accounts receivable	$ 489,069	$ 477,154
Unbilled receivables	510,760	468,824
Other	13,265	16,711
Less allowance for doubtful accounts	(5,364)	(5,402)
Receivables	$ 1,007,730	$ 957,287

Amount, before allowance for credit loss, of right to consideration from customer for product sold and service rendered in normal course of business, classified as current.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
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- Definition

Amount due from parties in nontrade transactions, classified as other.

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- Definition

Amount of expense (reversal of expense) for expected credit loss on accounts receivable.

+ References

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No definition available.

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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

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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.

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