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

No definition available.

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- Definition

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

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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- Definition

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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- Definition

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.

+ References

No definition available.

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- Definition

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

+ References

No definition available.

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Goodwill and Intangible Assets - Narrative (Details) - USD ($)		3 Months Ended		9 Months Ended
	Jul. 02, 2018	Jun. 30, 2019	Jul. 01, 2018	Jun. 30, 2019	Jul. 01, 2018	Sep. 30, 2018
Goodwill [Line Items]
Impairment of goodwill	$ 0
Estimated fair values that exceeded their carrying values, percent (more than)	30.00%
Amortization expense		$ 2,400,000	$ 5,200,000	$ 8,600,000	$ 14,900,000
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%
GSG
Goodwill [Line Items]
Gross amounts of goodwill		445,500,000		$ 445,500,000		$ 407,400,000
Accumulated impairment						17,700,000
CIG
Goodwill [Line Items]
Gross amounts of goodwill		521,700,000		521,700,000		507,000,000.0
Accumulated impairment		$ 97,900,000		$ 97,900,000		$ 97,900,000