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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Goodwill and Intangible Assets - Additional Information (Detail) - USD ($) $ in Millions	12 Months Ended
	Oct. 02, 2020	Sep. 27, 2019	Sep. 28, 2018	Jul. 03, 2020	Apr. 03, 2020
Finite-Lived Intangible Assets [Line Items]
Goodwill	$ 623.9	$ 612.2	$ 293.6
Amortization expense for intangible assets	38.2	27.3	20.6
Interventional Solutions Reporting Unit
Finite-Lived Intangible Assets [Line Items]
Goodwill					$ 164.3
Fair value in excess of carrying amount				$ 72.0
Percentage of fair value in excess of carrying amount				27.00%
Other
Finite-Lived Intangible Assets [Line Items]
Goodwill	$ 169.2	$ 164.3	$ 0.0
Other \| Interventional Solutions Reporting Unit
Finite-Lived Intangible Assets [Line Items]
Fair value in excess of carrying amount					$ 20.0
Percentage of fair value in excess of carrying amount					7.00%