Interim Financial Information - COVID-19 Pandemic (Details) $ in Millions	3 Months Ended
Mar. 31, 2020 USD ($)
Organization, Consolidation and Presentation of Financial Statements [Abstract]
One-time employee termination benefits associated with severance	$ 0.9
Additional used vehicle inventory reserves	4.8
Adjustment to credit losses as result of COVID-19	$ 0.4

Amount of expenses for special or contractual termination benefits provided to current employees involuntarily terminated under a benefit arrangement associated exit or disposal activities pursuant to an authorized plan. Excludes expenses related to one-time termination benefits, a discontinued operation or an asset retirement obligation.

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration