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Represents the number of locations through which floorplan financing was provided.

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Number of sites for whole car auctions.

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This element represents payments of contingent consideration and deferred acquisition costs for the period.

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No definition available.

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- Definition

Represents ADESA's rank among the largest providers of used vehicle auctions and related services.

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No definition available.

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For contingent consideration arrangements recognized in connection with a business combination, this element represents an estimate of the high-end of the potential range (undiscounted) of the consideration which may be paid.

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Amount of liability recognized arising from contingent consideration in a business combination.

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Amount after tax of increase (decrease) to equity or (increase) decrease to net assets, resulting from the cumulative effect adjustment of a new accounting principle applied in the period of adoption.

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No definition available.

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Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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Contractual interest rate for funds borrowed, under the debt agreement.

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The carrying amount of deferred costs.

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Amount of credit loss expense (reversal of expense) for financing receivable from change in methodology.

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Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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Basis of Presentation and Nature of Operations (Details) $ in Millions	3 Months Ended
	Mar. 31, 2020 USD ($) location network provider	Mar. 31, 2019 USD ($)	Dec. 31, 2019 USD ($)	Sep. 19, 2019 USD ($)	May 31, 2017 USD ($)
Basis of Presentation and Nature of Operations
Long-term debt	$ 1,912.7		$ 1,916.9
Payments of contingent consideration and deferred acquisition costs	22.3	$ 0.0
Opening balance adjustment for adoption of ASC Topic 326	$ 5.0	$ 0.0
ADESA Auctions
Basis of Presentation and Nature of Operations
Number of sites for whole car auctions \| network	74
Ranking of largest providers of used vehicle auctions and related services \| provider	2
AFC
Basis of Presentation and Nature of Operations
Number of floorplan financing locations \| location	123
Term Loan B-6
Basis of Presentation and Nature of Operations
Long-term debt	$ 945.2		947.6
Senior secured revolving credit facility
Basis of Presentation and Nature of Operations
Long-term debt	$ 0.0		0.0
Senior notes
Basis of Presentation and Nature of Operations
Senior notes stated interest rate	5.125%				5.125%
Long-term debt	$ 950.0		$ 950.0
Credit Agreement \| Term Loan B-6
Basis of Presentation and Nature of Operations
Long-term debt				$ 950.0
Credit Agreement \| Senior secured revolving credit facility
Basis of Presentation and Nature of Operations
Maximum borrowing capacity				$ 325.0
Credit Agreement \| 2017 Revolving Credit Facility
Basis of Presentation and Nature of Operations
Maximum borrowing capacity					$ 350.0
Accounting Standards Update 2016-13
Basis of Presentation and Nature of Operations
Opening balance adjustment for adoption of ASC Topic 326	5.0
Cumulative effect adjustment for adoption of new accounting standard, net of tax	3.8
Series of Individually Immaterial Business Acquisitions
Basis of Presentation and Nature of Operations
Fair value of deferred payments accrued	3.6
Fair value of estimated contingent payments accrued	40.8
Maximum amount of undiscounted deferred and contingent payments related to acquisitions	102.0
CarsOnTheWeb
Basis of Presentation and Nature of Operations
Payments of contingent consideration and deferred acquisition costs	$ 22.3