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aT3x Cuts and Jobs Act, Incomplete Accounting, Transition Tax for Accumulated Foreign Earnings, Provisional Income Tax Expense1

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Tax Cuts and Jobs Act, Transition Tax for Accumulated Foreign Earnings, Income Tax Expense1

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible operating loss carryforwards that are not subject to expiration dates.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible state and local operating loss carryforwards.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible research tax credit carryforwards.

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Amount of deferred tax assets for which it is more likely than not that a tax benefit will not be realized.

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Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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Amount of foreign earnings repatriated from subsidiaries outside the country of domicile.

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Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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The increase (decrease) during the reporting period in the account that represents the temporary difference that results from Income or Loss that is recognized for accounting purposes but not for tax purposes and vice versa.

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The amount of the tax credit carryforward, before tax effects, available to reduce future taxable income under enacted tax laws.

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Amount of undistributed earnings of foreign subsidiaries intended to be permanently reinvested outside the country of domicile.

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Amount of unrecognized tax benefits.

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The total amount of unrecognized tax benefits that, if recognized, would affect the effective tax rate.

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Income Taxes (Narrative) (Details) - USD ($) $ in Thousands	3 Months Ended			6 Months Ended	9 Months Ended	12 Months Ended
Income Taxes (Narrative) (Details) - USD ($) $ in Thousands	Jun. 28, 2019	Mar. 29, 2019	Dec. 28, 2018	Mar. 29, 2019	Jun. 28, 2019	Sep. 27, 2019	Sep. 28, 2018	Sep. 29, 2017	Sep. 30, 2016
Tax Credit Carryforward [Line Items]
Provision for income taxes						$ 26,802	$ 154,069	$ 48,039
Valuation allowance						24,884	16,256
Transition income tax expense for accumulated foreign earnings	$ (2,300)	$ 19,000	$ (36,000)	$ 19,000	$ (2,300)		$ 121,400
Transition tax for accumulated foreign earnings	$ 102,100
Net operating loss carryovers for California tax purposes						$ 4,900
Effective tax rate						9.50%	78.50%	18.80%
Foreign earnings repatriated						$ 300,000
Undistributed earnings of foreign subsidiaries						380,000
Unrecognized tax benefits, gross						108,539	$ 102,009	$ 98,665	$ 75,168
Unrecognized tax benefits if recognized, would affect our effective tax rate						72,800
Estimated decrease in unrecognized tax benefits due to lapse in statute of limitations						57,800
Increase in interest expense for current tax provision						3,500	3,000
NOL's not subject to expiration						8,300
R&D tax credit carryforwards						8,400
Foreign Tax Credit Carryforward
Tax Credit Carryforward [Line Items]
Tax credit carryforward						8,300
California Research Tax Credit Carryforward
Tax Credit Carryforward [Line Items]
Tax credit carryforward						30,300
Research Tax Credit Carryforward
Tax Credit Carryforward [Line Items]
Tax credit carryforward						3,100
Foreign Tax Authority
Tax Credit Carryforward [Line Items]
Valuation allowance						3,700
California \| State and Local Jurisdiction
Tax Credit Carryforward [Line Items]
Valuation allowance						$ 21,200
Impact Of Tax Cuts And Jobs Act
Tax Credit Carryforward [Line Items]
Provision for income taxes							$ 121,400
Impact Of Tax Cuts And Jobs Act, Repatriation Transition Tax
Tax Credit Carryforward [Line Items]
Increase (decrease) in deferred income taxes			36,000
Accounting Standards Update 2014-09
Tax Credit Carryforward [Line Items]
Increase (decrease) in deferred income taxes			$ (26,300)