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Revenue Accounting for Contracts / Accounting for Joint Ventures (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Mar. 30, 2018	Mar. 31, 2017	Mar. 30, 2018	Mar. 31, 2017
Revenue Accounting For Contracts Accounting For Joint Ventures [Abstract]
Pass-through costs included in revenues	$ 712,881	$ 560,566	$ 1,309,050	$ 1,233,545

X

- Definition

Pass through costs included in revenues.

+ References

No definition available.

+ Details

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X

- Definition

Revenue accounting for contracts / accounting for joint ventures.

+ References

No definition available.

+ Details

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