Revenue from Contracts with Customers (Contract Assets and Liabilities) (Details) - USD ($) $ in Thousands	Jun. 29, 2019	Sep. 30, 2018	Sep. 29, 2018
Revenue from Contract with Customer [Abstract]
Unbilled receivables	$ 444,762	$ 405,610	$ 316,489
Contract advances	147,677	152,608	$ 151,687
Net contract assets	$ 297,085	$ 253,002

Amount, after allowance for credit loss, of right to consideration in exchange for good or service transferred to customer when right is conditioned on something other than passage of time.

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Balance Type:	debit
Period Type:	instant

- Definition

The current portion of prepayments received from customers for goods or services to be provided in the future.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/otherTransitionRef
-Publisher FASB
-Name Accounting Standards Codification
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Balance Type:	credit
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- References

No definition available.

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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

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