Income Taxes (Details) - USD ($) $ in Millions	3 Months Ended		12 Months Ended
	Mar. 26, 2021	Mar. 27, 2020	Dec. 25, 2020
Income Taxes [Line Items]
Income tax benefit	$ (16.4)	$ (18.9)
Increase (decrease) tax benefit	(2.5)
(Loss) income from continuing operations before income taxes	$ (160.6)	$ (75.6)
Effective tax rate	10.20%	25.00%
Current Income Tax Expense (Benefit)	$ 13.0	$ (22.4)
Deferred Income Tax Expense (Benefit)	3.4	$ (3.5)
Income Taxes Paid, Net	8.1		$ 39.9
Unrecognized tax benefits	356.2		349.0
Unrecognized tax benefits, net increase	7.2
Unrecognized tax benefits, which if favorably settled would benefit the effective tax rate	80.9
Interest accrued on unrecognized tax benefits	19.8		$ 16.7
Unrecognized tax benefits that would impact effective tax rate, upper bound of change	41.7
Income tax penalties and interest accrued that would impact effective tax rate, upper bound of change	9.8
Increase (Decrease) Tax Expense (Benefit), Change in Operating Income	15.4
Increase (Decrease), Tax Expense (Benefit), CARES Act	11.0
Increase (Decrease), Tax Expense (Benefit), Uncertain Tax Positions	8.0
Increase (Decrease), Income Tax Expense (Benefit), Separation Costs, Reorganization Items, and Restructuring Charges	$ 1.1