CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (Parenthetical) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Unrealized gain (loss) on interest rate swaps, tax:
Unrealized gain arising during the period, tax provision (benefit)	$ 0.0	$ 0.0	$ (1.2)
Reclassification adjustment for gain included in floor plan interest expense, tax provision (benefit)	$ 0.0	$ 0.0	$ 0.3

Amount of tax expense (benefit) for reclassification of gain (loss) from accumulated other comprehensive income (AOCI) for derivative instrument designated and qualifying as cash flow hedge included in assessment of hedge effectiveness.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 220
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 12
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482790/220-10-45-12

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