The amount of expense recognized in the current period that reflects the allocation of the cost of tangible assets over the assets' useful lives. Includes production and non-production related depreciation.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=6391035&loc=d3e2868-110229

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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-SubTopic 10
-Section 45
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-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=121586364&loc=d3e3602-108585

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Amount before accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Topic 360
-SubTopic 10
-Section 50
-Paragraph 1
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-URI http://asc.fasb.org/extlink&oid=6391035&loc=d3e2868-110229

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.13)
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

+ References

No definition available.

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Summary of Significant Accounting Policies - Property and Equipment At Cost and Depreciable Useful Lives (Details) - USD ($) $ in Millions	12 Months Ended
	Jan. 03, 2021	Dec. 29, 2019	Dec. 30, 2018
Property, Plant and Equipment [Line Items]
Property and equipment	$ 222.3	$ 225.8
Depreciation expense	16.8	25.3	$ 24.0
Land
Property, Plant and Equipment [Line Items]
Property and equipment	0.0	0.0
Work in process
Property, Plant and Equipment [Line Items]
Property and equipment	0.4	2.7
Buildings and improvements
Property, Plant and Equipment [Line Items]
Property and equipment	$ 12.9	13.0
Buildings and improvements \| Minimum
Property, Plant and Equipment [Line Items]
Estimated useful life	15 years
Buildings and improvements \| Maximum
Property, Plant and Equipment [Line Items]
Estimated useful life	40 years
Computer hardware and software
Property, Plant and Equipment [Line Items]
Property and equipment	$ 152.3	153.1
Computer hardware and software \| Minimum
Property, Plant and Equipment [Line Items]
Estimated useful life	3 years
Computer hardware and software \| Maximum
Property, Plant and Equipment [Line Items]
Estimated useful life	12 years
Equipment, furniture and fixtures
Property, Plant and Equipment [Line Items]
Property and equipment	$ 34.8	34.1
Estimated useful life	5 years
Leasehold improvements
Property, Plant and Equipment [Line Items]
Property and equipment	$ 21.9	$ 22.9
Leasehold improvements \| Headquarters
Property, Plant and Equipment [Line Items]
Estimated useful life	15 years
Leasehold improvements \| Maximum \| Branches
Property, Plant and Equipment [Line Items]
Estimated useful life	5 years