Goodwill and Intangible Assets (Details 2) (USD $)	3 Months Ended
Dec. 28, 2014	Dec. 29, 2013	Sep. 28, 2014
Finite-lived intangible assets
Gross Amount	$ 124,155,000		$ 127,484,000
Accumulated Amortization	(68,266,000)		(64,389,000)
Foreign currency translation adjustments	1,300,000
Amortization expense for identifiable intangible assets	5,900,000us-gaap_AmortizationOfIntangibleAssets	8,600,000us-gaap_AmortizationOfIntangibleAssets
Estimated amortization expense
2015	14,327,000
2016	16,713,000
2017	13,987,000
2018	5,968,000
2019	2,887,000
Beyond	2,007,000
Total	55,889,000us-gaap_FiniteLivedIntangibleAssetsNet
Non-compete agreements
Finite-lived intangible assets
Weighted-Average Remaining Life	1 year 10 months 24 days
Gross Amount	1,033,000		1,086,000
Accumulated Amortization	(562,000)		(524,000)
Client relations
Finite-lived intangible assets
Weighted-Average Remaining Life	3 years 7 months 6 days
Gross Amount	119,098,000		122,198,000
Accumulated Amortization	(64,742,000)		(61,117,000)
Backlog
Finite-lived intangible assets
Weighted-Average Remaining Life	1 month 6 days
Gross Amount	1,209,000		1,283,000
Accumulated Amortization	(1,174,000)		(1,072,000)
Technology and trade names
Finite-lived intangible assets
Weighted-Average Remaining Life	1 year 10 months 24 days
Gross Amount	2,815,000		2,917,000
Accumulated Amortization	$ (1,788,000)		$ (1,676,000)

Weighted average amortization period of finite-lived intangible assets acquired either individually or as part of a group of assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

+ References

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Accumulated amount of amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized after the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized in the remainder of the fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized during the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized during the fourth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized during the third fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized during the second fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount before amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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Amount after amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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Amount of increase (decrease) to assets, excluding financial assets and goodwill, lacking physical substance with a finite life for foreign currency translation adjustments.

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