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Significant Accounting Policies (Pass-Through Costs Included in Revenues) (Details) - USD ($) $ in Millions	12 Months Ended
	Sep. 29, 2017	Sep. 30, 2016	Oct. 02, 2015
Accounting Policies [Abstract]
Pass-through costs included in revenues	$ 2,539.3	$ 2,489.9	$ 2,602.6

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- Definition

Pass through costs included in revenues.

+ References

No definition available.

+ Details

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Balance Type:	debit
Period Type:	duration

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- References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
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Period Type:	duration