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Fair Value Measurements - Additional Information (Detail) - USD ($)	3 Months Ended		6 Months Ended
	Mar. 30, 2019	Mar. 31, 2018	Mar. 30, 2019	Mar. 31, 2018
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Intangible asset and equipment impairment charges	$ 443,800,000		$ 443,800,000	$ 46,000,000
Goodwill impairment charge	0	$ 685,700,000	0	$ 685,700,000
Borrowed principal	1,000,000,000		1,000,000,000
Credit Agreement
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Borrowed principal	1,600,000,000		1,600,000,000
Securitization Program
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Borrowed principal	207,000,000		207,000,000
2025 Senior Notes
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Fair value of debt instrument	939,300,000		939,300,000
2028 Senior Notes
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Fair value of debt instrument	395,900,000		395,900,000
Medical Aesthetics
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Intangible asset and equipment impairment charges	443,800,000
Goodwill impairment charge		685,700,000
Carrying value of indefinite-lived intangibles	0		$ 0
In Process Research and Development [Member] \| Medical Aesthetics
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Intangible asset and equipment impairment charges		$ 46,000,000
Acquired intangible assets [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Intangible asset and equipment impairment charges	437,000,000
Property, Plant and Equipment [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Intangible asset and equipment impairment charges	6,800,000
Property, Plant and Equipment [Member] \| Medical Aesthetics
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Intangible asset and equipment impairment charges	$ 6,800,000