Relationship with KAR and Related Entities - Narrative (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 28, 2020	Jun. 30, 2019	Jun. 28, 2020	Jun. 30, 2019
Related Party Transaction [Line Items]
Selling, general and administrative	$ 34.3	$ 33.7	$ 72.3	$ 67.3
Cost of products and services obtained	185.1	227.7	$ 416.1	446.1
Non-compete period			5 years
Services period			2 years
Affiliated Entity
Related Party Transaction [Line Items]
Cost of products and services obtained	$ 0.2	0.2	$ 0.5	0.5
Corporate
Related Party Transaction [Line Items]
Selling, general and administrative		$ 1.1		$ 2.8

Separation And Distribution Agreement, Non-Compete Period

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Transition Services Agreement, Services Period

+ References

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- Definition

Cost of product sold and service rendered, excluding depreciation, depletion, and amortization.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03(2)(a))
-URI http://asc.fasb.org/extlink&oid=120395209&loc=SL114868664-224227

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03(2)(d))
-URI http://asc.fasb.org/extlink&oid=120395209&loc=SL114868664-224227

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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

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The aggregate total costs related to selling a firm's product and services, as well as all other general and administrative expenses. Direct selling expenses (for example, credit, warranty, and advertising) are expenses that can be directly linked to the sale of specific products. Indirect selling expenses are expenses that cannot be directly linked to the sale of specific products, for example telephone expenses, Internet, and postal charges. General and administrative expenses include salaries of non-sales personnel, rent, utilities, communication, etc.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.4)
-URI http://asc.fasb.org/extlink&oid=120395209&loc=SL114868664-224227

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