[Line Items] for Income Taxes [Table]

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from intangible assets including goodwill.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible operating loss carryforwards.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible operating loss carryforwards that are not subject to expiration dates.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible operating loss carryforwards that are subject to expiration dates.

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Amount of deferred tax assets for which it is more likely than not that a tax benefit will not be realized.

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Percentage of domestic federal statutory tax rate applicable to pretax income (loss).

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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 the disposition of a business not qualifying as a discontinued operation.

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The amount of the unrecognized tax benefit of a position taken for which it is reasonably possible that the total amount thereof will significantly increase or decrease within twelve months of the balance sheet date.

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The amount of the tax credit carryforward, before tax effects, available to reduce future taxable income under enacted tax laws.

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Amount of undistributed earnings of foreign subsidiaries intended to be permanently reinvested outside the country of domicile.

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Amount of unrecognized tax benefits.

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Amount accrued for interest on an underpayment of income taxes and penalties related to a tax position claimed or expected to be claimed in the tax return.

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Amount of interest expense accrued for an underpayment of income taxes.

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The total amount of unrecognized tax benefits that, if recognized, would affect the effective tax rate.

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Income Taxes - Narrative (Details) - USD ($) $ in Millions	12 Months Ended
Income Taxes - Narrative (Details) - USD ($) $ in Millions	Jan. 03, 2021	Dec. 29, 2019	Dec. 30, 2018	Dec. 31, 2017
Income Taxes [Line Items]
Loss carryforwards	$ 33.6	$ 30.4
Operating loss carryforwards, not subject to expiration	$ 31.7
U.S. statutory rate	21.00%	21.00%
Income tax expense (benefit)	$ (34.0)	$ 0.4	$ (27.1)
Disposition of business	(6.6)	0.0	0.0
Valuation allowance	20.2	19.0
Undistributed earnings of foreign subsidiaries	135.2
Unrecognized tax benefits	0.5	0.9	1.1	$ 1.2
Unrecognized tax benefits, interest on income taxes accrued	0.1
Unrecognized tax benefits that would impact effective tax rate	0.4	0.8	0.9
Unrecognized tax benefits, income tax penalties and interest accrued	0.1	0.2
Significant change in unrecognized tax benefits is reasonably possible, amount of unrecorded benefit	0.1
Deferred Tax Assets, Goodwill and Intangible Assets	(23.0)
Expiring in Years 2021 to 2037
Income Taxes [Line Items]
Subject to expiration	1.9
General Business Tax Credit Carryforward
Income Taxes [Line Items]
General business credit carryforward	153.3
Foreign Tax Credit Carryforward
Income Taxes [Line Items]
General business credit carryforward	7.8
State Credit Carryforward
Income Taxes [Line Items]
General business credit carryforward	0.1
Pro Forma
Income Taxes [Line Items]
Potential repatriation of foreign earnings amount	7.6
Germany
Income Taxes [Line Items]
Valuation allowance		3.9
United Kingdom
Income Taxes [Line Items]
Income tax expense (benefit)		(14.3)
Persol Holdings Investment
Income Taxes [Line Items]
Income tax expense (benefit)	$ (5.1)	$ 11.0	$ (29.4)