Effective Income Tax Rate Reconciliation, Tax Cuts and Jobs Act, Amount

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Effective Income Tax Rate Reconciliation, Tax Cuts and Jobs Act, Transition Tax on Accumulated Foreign Earnings, Amount

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Income Tax Reconciliation, Changes to Indefinite Life Items and Separate State Deferred Taxes

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Income Tax Reconciliation, Release Of Valuation Allowance, Business Combination

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Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to increase (decrease) in the valuation allowance for deferred tax assets.

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Amount of difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying domestic federal statutory income tax rates to pretax income (loss) from continuing operations, attributable to disposition of asset. Includes, but is not limited to, intra-entity transfer of asset other than inventory.

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The amount of income tax expense or benefit for the period computed by applying the domestic federal statutory tax rates to pretax income from continuing operations.

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Amount of reported income tax expense (benefit) in excess of (less than) expected income tax expense (benefit) computed by applying domestic federal statutory income tax rate to pretax income (loss) from continuing operation, attributable to nondeductible expense for award under share-based payment arrangement. Includes, but is not limited to, expense determined to be nondeductible upon grant or after for award under share-based payment arrangement.

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Income Taxes - Reconciliation of Income Tax Provision (Details) - USD ($) $ in Millions	3 Months Ended								12 Months Ended
	Dec. 29, 2019	Sep. 29, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 30, 2018	Sep. 30, 2018	Jul. 01, 2018	Apr. 01, 2018	Dec. 29, 2019	Dec. 30, 2018	Dec. 31, 2017
Income Tax Disclosure [Abstract]
Income tax (benefit) at federal statutory rate									$ 3.3	$ 1.8	$ (20.0)
State taxes, net of federal tax benefit and valuation allowance									0.6	0.9	0.5
Difference in tax rates between U.S. and foreign									1.9	0.7	0.0
Increase (decrease) in valuation allowance									(3.3)	4.7	(45.6)
Nondeductible expense									1.0	0.6	1.1
Increase in reserve for uncertain tax positions									7.7	4.0	1.3
Changes to indefinite life items and separate state deferred taxes									0.4	(0.7)	(1.8)
One-time transition tax on previously undistributed foreign earnings									0.0	2.2	6.2
Goodwill impairment									0.0	0.0	8.1
Decrease in deferred taxes related to disposition									0.0	(9.6)	0.0
Impact related to the 2017 Tax Cuts and Jobs Act									0.0	0.0	40.0
Release of valuation allowance due to FTT acquisition									(5.2)	0.0	0.0
Stock-based compensation									(1.6)	0.0	0.0
Total	$ 1.0	$ 2.8	$ 2.5	$ (1.5)	$ 0.2	$ 3.4	$ 0.1	$ 0.9	$ 4.8	$ 4.6	$ (10.2)