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Amount of impairment loss resulting from write-down of assets, excluding financial assets and goodwill, lacking physical substance and having a projected indefinite period of benefit to fair value.

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Fair Value Measurements - Additional Information (Detail) - USD ($)	3 Months Ended			9 Months Ended
	Jun. 30, 2018	Mar. 31, 2018	Jul. 01, 2017	Jun. 30, 2018	Jul. 01, 2017	Sep. 30, 2017	Mar. 22, 2017
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Impairment of indefinite intangible assets	$ 0		$ 0	$ 46,000,000	$ 0
Goodwill impairment charge	0		$ 0	685,700,000	$ 0
Carrying value of goodwill	2,493,400,000			2,493,400,000		$ 3,171,200,000
Borrowed principal	1,000,000,000			1,000,000,000
Credit Agreement
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Borrowed principal	1,700,000,000			1,700,000,000
Securitization Program
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Borrowed principal	219,800,000			219,800,000
2025 Senior Notes
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Fair value of debt instrument	907,800,000			907,800,000
2028 Senior Notes
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Fair value of debt instrument	377,300,000			377,300,000
Medical Aesthetics
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Goodwill impairment charge		$ 685,700,000
Carrying value of goodwill	0			0
Carrying value of indefinite-lived intangibles	$ 0			$ 0
In-process research and development \| Medical Aesthetics
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Impairment of indefinite intangible assets		46,000,000
Cynosure
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Carrying value of goodwill							$ 685,700,000
Cynosure \| Medical Aesthetics
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Goodwill impairment charge		$ 685,700,000