Income Taxes - Additional Information (Detail) - USD ($)	3 Months Ended				12 Months Ended
	Sep. 26, 2020	Dec. 29, 2018	Sep. 29, 2018	Mar. 31, 2018	Sep. 26, 2020	Sep. 28, 2019	Sep. 29, 2018
Income Taxes [Line Items]
Provisional estimate of tax benefit as result of Tax Cuts and Jobs Act		$ 341,200,000	$ 346,400,000				$ 346,200,000
Decrease in valuation allowance					$ (57,800,000)
Net operating losses	$ 32,200,000				32,200,000
Federal net operating loss expected to be expired unutilized	4,500,000				4,500,000
State net operating loss expected to be expired unutilized	74,600,000				74,600,000
Foreign net operating loss expected to be expired unutilized	47,200,000				47,200,000
Gross unrecognized tax benefits, excluding interest	197,100,000				197,100,000	$ 101,600,000
Unrecognized tax benefit that would impact effective tax rate	184,900,000				184,900,000	87,300,000
Change in gross unrecognized tax benefits						95,500,000
Interest accrued on unrecognized tax benefits	11,900,000				11,900,000	11,100,000
Income tax penalties accrued	0				0
Increase in deferred tax assets resulting from adoption of ASU 2016-16					2,900,000
Decease in accumulated deficit resulting from adoption of ASU 2016-16					2,500,000
Decease to prepaid taxes resulting from adoption of ASU 2016-16					400,000
Increase to income tax expense adoption of ASU 2016-16					27,800,000
Decrease in deferred tax liabilities due to ASU 2016-16					37,700,000
Increase to Net Income resulted from adoption of ASU 2016-16					$ 9,900,000
Increase to Earnings per Share resulted from adoption of ASU 2016-16					$ 0.04
state loss carryforward expected to unutilize	26,100,000				$ 26,100,000
Capital losses	57,000,000.0				57,000,000.0	$ 6,400,000
Gross state loss carryforwards	0.0				0.0
Gross foreign loss carryforwards	32,200,000				32,200,000
Medical Aesthetics
Income Taxes [Line Items]
Other Tax Expense (Benefit)					313,400,000
General and Administrative Expense
Income Taxes [Line Items]
Non-income tax loss	(2,900,000)			$ (4,000,000.0)
Net Operating Losses Carryforwards
Income Taxes [Line Items]
Amount with unlimited carry forward periods					22,500,000
Tax Credit Carryforward
Income Taxes [Line Items]
Amount with unlimited carry forward periods					3,400,000
Maximum
Income Taxes [Line Items]
Decrease in unrecognized tax benefits is reasonably possible	1,300,000				1,300,000
Domestic Tax Authority
Income Taxes [Line Items]
Net operating losses	40,100,000				40,100,000
Credit carry forwards	5,000,000.0				5,000,000.0
State and Local Jurisdiction
Income Taxes [Line Items]
Net operating losses	44,500,000				44,500,000
Credit carry forwards	4,500,000				4,500,000
Foreign Tax Authority
Income Taxes [Line Items]
Net operating losses	207,100,000				207,100,000
Credit carry forwards	$ 1,200,000				$ 1,200,000