Represents the weighted percentage used in the fair value measurement of goodwill.

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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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- Definition

Sum of the carrying amounts as of the balance sheet date of all assets that are recognized. Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Amount before accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Amount of accumulated impairment loss for an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Amount of loss from the write-down of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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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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Percentage of fair value of reporting unit in excess of carrying amount.

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Goodwill and Intangible Assets - Narrative (Details) - USD ($)		3 Months Ended			6 Months Ended
	Jul. 01, 2019	Mar. 29, 2020	Sep. 29, 2019	Mar. 31, 2019	Mar. 29, 2020	Mar. 31, 2019
Goodwill [Line Items]
Impairment of goodwill	$ 0
Estimated fair values that exceeded their carrying values, percent	25.00%
Goodwill		$ 944,718,000	$ 924,820,000		$ 944,718,000
Assets		2,343,150,000	2,147,408,000		2,343,150,000
Amortization expense		$ 3,400,000		$ 2,200,000	$ 6,400,000	$ 6,200,000
Income approach, discounted cash flow method
Goodwill [Line Items]
Weighted rate used in fair value of goodwill (as a percent)					70.00%
Market approach
Goodwill [Line Items]
Weighted rate used in fair value of goodwill (as a percent)					30.00%
RFS
Goodwill [Line Items]
Impairment of goodwill			7,800,000
Estimated fair values that exceeded their carrying values, percent		20.00%			20.00%
Goodwill		$ 48,000,000	48,800,000		$ 48,000,000
Assets			61,000,000
ASP
Goodwill [Line Items]
Estimated fair values that exceeded their carrying values, percent		20.00%			20.00%
Goodwill		$ 102,000,000			$ 102,000,000
GSG
Goodwill [Line Items]
Gross amounts of goodwill		491,000,000.0	459,500,000		491,000,000.0
Accumulated impairment		17,700,000	17,700,000		17,700,000
Goodwill		473,303,000	441,802,000		473,303,000
CIG
Goodwill [Line Items]
Gross amounts of goodwill		577,100,000	588,700,000		577,100,000
Accumulated impairment		105,700,000	105,700,000		105,700,000
Goodwill		$ 471,415,000	$ 483,018,000		$ 471,415,000