Receivables (Details) - USD ($) $ in Thousands	3 Months Ended
Apr. 01, 2016	Oct. 02, 2015
Components of receivables:
Amounts billed	$ 1,170,483	$ 1,213,892
Unbilled receivables and other	1,159,548	1,252,509
Retentions receivable	85,061	82,342
Total receivables, net	2,415,092	2,548,743
Other information about receivables:
Amounts due from the United States federal government, included above, net of advanced billings	284,833	327,157
Claims receivable	$ 9,291	$ 32,511
Duration which unbilled amounts will be billed and collected over (duration)	12 months

Other Information About Receivables [Abstract]

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- Definition

Unbilled Amounts Billed And Collected

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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

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- Definition

Amount billed to customers under long-term contracts or programs that have been withheld because of retainage provisions in a contract.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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Amount of billed or unbilled claims or other similar items subject to uncertainty concerning their determination or ultimate realization under long-term contracts.

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- Definition

Amounts due within 1 year (or 1 business cycle) from other related parties which are not otherwise stated in the taxonomy.

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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.

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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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