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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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Fair value portion of investment securities, including, but not limited to, marketable securities, derivative financial instruments, and investments accounted for under the equity method.

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Fair Value Measurements - Additional Information (Detail) - USD ($)	3 Months Ended					12 Months Ended
	Sep. 26, 2020	Mar. 28, 2020	Dec. 28, 2019	Mar. 30, 2019	Mar. 31, 2018	Sep. 26, 2020	Sep. 28, 2019	Sep. 29, 2018
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Investments, fair value	$ 11,200,000					$ 11,200,000	$ 7,700,000
Borrowed principal under credit agreement	1,000,000,000.0					1,000,000,000.0
Impairment of intangible assets and equipment	241,600,000	$ 443,800,000	$ 30,200,000			4,400,000	106,700,000	$ 46,000,000.0
Goodwill impairment charge					$ 685,700,000	0	0	$ 685,700,000
Impairment charge			$ 30,200,000	$ 685,400,000
Medical Aesthetics Business
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Goodwill impairment charge					$ 685,700,000
Medical Aesthetics Business \| Acquired intangible assets [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Impairment charge				675,600,000
Medical Aesthetics Business \| Equipment [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Impairment charge				$ 9,800,000
Credit Agreement
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Borrowed principal under credit agreement	1,710,000,000					1,710,000,000
Significant Unobservable Inputs (Level 3)
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Investments, fair value	0					0	$ 0
2028 Senior Notes
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Fair value of debt instrument	419,100,000					419,100,000
2025 Senior Notes
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Fair value of debt instrument	$ 971,500,000					$ 971,500,000