Income Taxes - Provision for Income Taxes (Detail) - USD ($) $ in Millions	12 Months Ended
Sep. 26, 2020	Sep. 28, 2019	Sep. 29, 2018
Federal:
Current	$ (62.1)	$ 142.9	$ 137.1
Deferred	(76.6)	(189.9)	(461.9)
Federal, Total	(138.7)	(47.0)	(324.8)
State:
Current	33.9	22.1	11.0
Deferred	(12.5)	(41.0)	(11.3)
State, Total	21.4	(18.9)	(0.3)
Foreign:
Current	14.0	16.5	21.9
Deferred	(5.3)	(4.7)	(4.1)
Foreign, Total	8.7	11.8	17.8
Provision for income taxes	$ (108.6)	$ (54.1)	$ (307.3)

Amount of current federal tax expense (benefit) pertaining to income (loss) from continuing operations.

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