Operating (Gains), Losses and Other Charges, Net - Narrative (Details) $ in Millions	6 Months Ended
Jun. 30, 2021 USD ($) real_estate parcel	Jun. 24, 2020 parcel	Dec. 30, 2020 USD ($) real_estate
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Exit cost liabilities	$ 0.1		$ 0.1
Severance and other restructuring charges	0.7		0.6
Held-for-sale
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Carrying amount	$ 1.6		1.1
Property			1.0
Other assets			$ 0.1
Number of real estate properties \| real_estate	2		2
Real Estate
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Number of real estate properties sold \| parcel	1	2

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