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.

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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 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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Goodwill and Intangible Assets - Finite Lived Assets (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Jul. 01, 2018	Jul. 02, 2017	Jul. 01, 2018	Jul. 02, 2017	Oct. 01, 2017
Finite-lived intangible assets
Gross Amount	$ 82,254		$ 82,254		$ 118,995
Accumulated Amortization	(66,876)		(66,876)		(92,307)
Amortization expense	5,200	$ 5,600	14,900	$ 17,400
Estimated amortization expense
2018	4,043		4,043
2019	6,295		6,295
2020	2,758		2,758
2021	1,642		1,642
2022	411		411
Beyond	229		229
Total	15,378		$ 15,378
Non-compete agreements
Finite-lived intangible assets
Weighted- Average Remaining Life (in Years)			0 years
Gross Amount	81		$ 81		495
Accumulated Amortization	(81)		$ (81)		(493)
Client relations
Finite-lived intangible assets
Weighted- Average Remaining Life (in Years)			2 years 7 months 6 days
Gross Amount	54,446		$ 54,446		90,297
Accumulated Amortization	(44,589)		$ (44,589)		(75,074)
Trade names
Finite-lived intangible assets
Weighted- Average Remaining Life (in Years)			9 months 18 days
Gross Amount	22,620		$ 22,620		21,518
Accumulated Amortization	(19,301)		$ (19,301)		(13,301)
Trade names
Finite-lived intangible assets
Weighted- Average Remaining Life (in Years)			2 years 6 months
Gross Amount	5,107		$ 5,107		6,685
Accumulated Amortization	$ (2,905)		$ (2,905)		$ (3,439)