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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-Publisher FASB
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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.

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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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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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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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Goodwill and Intangible Assets - Finite Lived Assets (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Jul. 02, 2017	Jun. 26, 2016	Jul. 02, 2017	Jun. 26, 2016	Oct. 02, 2016
Finite-lived intangible assets
Gross Amount	$ 117,236		$ 117,236		$ 144,044
Accumulated Amortization	(85,441)		(85,441)		(95,082)
Amortization expense	5,600	$ 6,300	17,400	$ 16,100
Estimated amortization expense
2017	5,280		5,280
2018	14,453		14,453
2019	6,997		6,997
2020	2,765		2,765
2021	1,660		1,660
Beyond	640		640
Total	31,795		$ 31,795
Non-compete agreements
Finite-lived intangible assets
Weighted-Average Remaining Life (in Years)			3 months 18 days
Gross Amount	484		$ 484		881
Accumulated Amortization	(477)		$ (477)		(840)
Client relations
Finite-lived intangible assets
Weighted-Average Remaining Life (in Years)			2 years 9 months 18 days
Gross Amount	88,940		$ 88,940		112,367
Accumulated Amortization	(70,572)		$ (70,572)		(83,514)
Backlog
Finite-lived intangible assets
Weighted-Average Remaining Life (in Years)			1 year 6 months
Gross Amount	21,252		$ 21,252		23,018
Accumulated Amortization	(11,377)		$ (11,377)		(7,536)
Technology and trade names
Finite-lived intangible assets
Weighted-Average Remaining Life (in Years)			3 years 4 months 24 days
Gross Amount	6,560		$ 6,560		7,778
Accumulated Amortization	$ (3,015)		$ (3,015)		$ (3,192)