Income Taxes (Narrative) (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
Oct. 02, 2020	Sep. 27, 2019	Sep. 28, 2018
Income Taxes [Line Items]
United States tax rate	21.00%	21.00%	24.60%
Foreign tax rate difference	$ (86,600)	$ (115,300)	$ (111,900)
Income tax holiday	September 30, 2030
Impact of tax holiday	$ 63,100	$ 32,800	$ 38,400
Impact of tax holiday on diluted earnings per share (in dollars per share)	$ 0.37	$ 0.19	$ 0.21
Valuation Allowance, Amount	$ 137,400	$ 129,100
Tax benefit to recognize if valuation allowance is reversed	137,400
Future taxable income needed to utilize deferred tax assets	124,100
Valuation Allowance, Deferred Tax Asset, Increase (Decrease), Amount	8,300	10,500
Total unrecognized tax benefits that would impact the effective tax rate	95,300
Unrecognized Tax Benefits, Income Tax Penalties and Interest Expense	4,600	6,000	$ 4,100
Previously unrecognized tax benefits related to the expiration of the statute of limitations	100
Decreases relating to settlements with taxing authorities	0
Accrued interest or penalties related to unrecognized tax benefit	16,100	12,700
Effective Income Tax Rate Reconciliation, Repatriation of Foreign Earnings, Amount	200	8,100	224,600
Effective Income Tax Rate Reconciliation, Change in Enacted Tax Rate, Amount	0	0	18,300
EffectiveIncomeTaxRateReconciliationGlobalIntangibleLowTaxedIncomeAmount	35,900	54,300	0
EffectiveIncomeTaxRateReconciliationForeignDerivedIntangibleIncome	(41,200)	(41,500)	$ 0
Income Tax Examination, Penalties and Interest Accrued	3,800
Foreign Tax Authority [Member]
Income Taxes [Line Items]
Valuation Allowance, Amount	18,600
State and Local Jurisdiction [Member]
Income Taxes [Line Items]
Valuation Allowance, Amount	118,800
Tax credit carryforward	115,400
UNITED STATES
Income Taxes [Line Items]
Federal net operating loss carry forwards	$ 8,100
Open tax year	2001
CALIFORNIA
Income Taxes [Line Items]
Open tax year	1999
CANADA
Income Taxes [Line Items]
Open tax year	2013
MEXICO
Income Taxes [Line Items]
Open tax year	2014
JAPAN
Income Taxes [Line Items]
Open tax year	2014
SINGAPORE
Income Taxes [Line Items]
Open tax year	2014
Other Current Liabilities [Member]
Income Taxes [Line Items]
Foreign Earnings Repatriated	$ 18,600	18,800
Other Noncurrent Liabilities [Member]
Income Taxes [Line Items]
Foreign Earnings Repatriated	$ 177,000	$ 195,900

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