CONSOLIDATED CONDENSED STATEMENTS OF CASH FLOWS (Parenthetical) - USD ($) $ in Millions	6 Months Ended
Jun. 30, 2022	Jun. 30, 2021
Debt Instrument [Line Items]
Repayment of sellers' floor plan notes payable dealership acquisitions	$ 51.3	$ 24.3
3.75% senior subordinated notes due 2029
Debt Instrument [Line Items]
Interest rate (as a percent)	3.75%
5.50% senior subordinated notes due 2026
Debt Instrument [Line Items]
Interest rate (as a percent)	5.50%

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

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 1B
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=123466505&loc=SL123495323-112611

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 210.5-02.22(a)(1))
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

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Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant