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Amount of increase (decrease) in the valuation allowance for a specified deferred tax asset.

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Income Taxes (Details) - USD ($) $ in Billions	3 Months Ended			12 Months Ended
Income Taxes (Details) - USD ($) $ in Billions	Jun. 28, 2026	Mar. 29, 2026	Jun. 29, 2025	Sep. 27, 2026	Sep. 28, 2025
Income Taxes
Effective income tax rate (benefit)	19.00%		10.00%
U.S. Federal
Valuation Allowance [Line Items]
Valuation Allowance, Deferred Tax Asset, Increase (Decrease), Amount		$ (5.7)			$ 5.7
Forecast
Income Taxes
Effective income tax rate (benefit)				(40.00%)
Forecast \| FDDEI effective Tax Rate
Income Taxes
Effective income tax rate (benefit)				13.00%