Income Taxes (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended	12 Months Ended
Jun. 30, 2018	Jul. 01, 2017	Jun. 30, 2018	Jul. 01, 2017	Dec. 30, 2017
Income Tax Disclosure [Abstract]
Effective tax rate	27.00%	31.00%	22.00%	29.00%
Impact of investments in unconsolidated affiliates			$ 3.7	$ 0.8
Provision for state income taxes, net of federal benefits	$ 1.4	$ 0.8	2.6	1.7
Global intangible low-taxed income			1.0
Other items	$ 1.3	0.2	$ 1.2	$ 0.7
Statutory income tax rate			21.00%	35.00%
Reduction for U.S. production activities		0.9		$ 1.8
Effect of foreign adjustments		$ 1.6		3.0
Tax benefit of equity compensation deductions				$ 1.7
One-time transition tax liability			$ 12.9		$ 12.9
Provisional tax benefit			$ 12.1		$ 12.1

Effective Income Tax Rate Reconciliation, Global Intangible Low-Taxed Income, Amount

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Tax Cuts And Jobs Act Of 2017, Incomplete Accounting, Provisional Income Tax Expense (Benefit)

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Tax Cuts and Jobs Act of 2017, Incomplete Accounting, Transition Tax for Accumulated Foreign Earnings, Provisional Income Tax Expense

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Percentage 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 the expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to deduction for qualified production activity.

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