Income Taxes (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 28, 2019	Jun. 29, 2018	Jun. 28, 2019	Jun. 29, 2018	Dec. 28, 2018
Income Taxes [Line Items]
Income tax benefit	$ 24.3	$ 44.4	$ 229.0	$ 81.0
Increase (decrease) tax benefit	20.1		(148.0)
Increase (Decrease) Tax Benefit, Intercompany Financing Reorganization			189.8
Loss (income) from continuing operations before income taxes	$ 24.8	$ 41.2	$ 74.3	$ 98.7
Effective tax rate	98.00%	107.80%	308.20%	82.10%
Current Income Tax Expense (Benefit)	$ 5.6	$ 10.2	$ 44.1	$ 21.4
Deferred Income Tax Expense (Benefit)	(29.9)	$ (54.6)	(273.1)	$ (102.4)
Deferred Tax Liabilities Installment Sales	0.0		0.0		$ 227.5
Income Taxes Paid, Net			21.5		12.4
Operating Loss Carryforwards	815.4		815.4
Operating Loss Carryforward, Measured at Applicable Statutory Tax Rates	171.2		171.2
Unrecognized tax benefits	448.9		448.9		287.7
Unrecognized tax benefits, net increase			161.2
Unrecognized Tax Benefits, Increase Resulting from Current Period Tax Positions			151.7
Unrecognized tax benefits, net increase related to prior period tax positions			13.7
Unrecognized Tax Benefits, Decrease Resulting from Settlements with Taxing Authorities			0.9
Unrecognized Tax Benefits, Reduction Resulting from Lapse of Applicable Statute of Limitations			3.3
Unrecognized tax benefits, which if favorably settled would benefit the effective tax rate	437.4		437.4
Interest accrued on unrecognized tax benefits	44.6		44.6		$ 37.1
Unrecognized tax benefits that would impact effective tax rate, upper bound of change	102.8		102.8
Income tax penalties and interest accrued that would impact effective tax rate, upper bound of change	(32.5)		(32.5)
Increase (Decrease) Tax Expense (Benefit), Change in Operating Income	20.7		35.2
Increase (Decrease), Tax Expense (Benefit), Gain on Debt Repurchases	7.1		8.9
Increase (Decrease), Tax Expense (Benefit), Restructuring	3.4		9.8
Increase (Decrease), Tax Expense (Benefit), Non-restructuring Impairment Charge	(8.5)		(8.5)
Increase (Decrease), Tax Expense (Benefit), Separation Costs	(2.6)		(3.6)
Increase (Decreased) Deferred Tax Asset, Change in Statutory Tax Rate			65.8
Discontinued Operations [Member]
Income Taxes [Line Items]
Unrecognized tax benefits, which if favorably settled would benefit the effective tax rate	$ 20.0		20.0
Intercompany Financing and Legal Entity Ownership Reorganization [Member]
Income Taxes [Line Items]
Increase (Decrease) in Deferred Tax Liabilities, Other			26.4
Increase (Decrease) Deferred Tax Asset, Tax Loss and Credit Carryforwards			(24.7)
Current Income Tax Expense (Benefit)			28.9
Deferred Income Tax Expense (Benefit)			(218.7)
Increase (decrease), deferred tax assets, excess interest carryforwrds			$ 42.3
Luxembourg [Member]
Income Taxes [Line Items]
Effective tax rate			24.94%		26.01%