The amount of notes payable attributable to the floor plan.

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Amounts borrowed to finance the purchase of specific new and program vehicle inventories with lenders that are not captive finance subsidiaries of the manufacturer.

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The amount of debt associated with the floor plan.

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

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Amount, after accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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Credit Facilities and Long-term Debt - Schedule of Credit Facilities and Long-term Debt (Details) - USD ($) $ in Millions	Dec. 31, 2021	Aug. 01, 2021	May 27, 2021	Dec. 31, 2020
Debt Instrument [Line Items]
Floor plan notes payable: non-trade	$ 835.9			$ 1,563.0
Floor plan notes payable	354.2			234.2
Total floor plan debt	1,190.1			1,797.2
Finance lease obligations	53.6			246.4
Total long-term debt outstanding	3,435.9			2,149.3
Less: unamortized debt issuance costs	(26.5)			(18.6)
Less: current maturities (net of current debt issuance costs)	(223.7)			(66.0)
Long-term debt	3,185.7			2,064.7
Other debt
Debt Instrument [Line Items]
Long-term debt, gross	1.9			2.4
Line of Credit \| Used and service loaner vehicle inventory financing commitments
Debt Instrument [Line Items]
Long-term debt, gross	500.0			0.0
Line of Credit \| Revolving lines of credit
Debt Instrument [Line Items]
Long-term debt, gross	219.9			39.0
Real estate mortgages
Debt Instrument [Line Items]
Long-term debt, gross	592.9			611.5
Non-recourse notes payable
Debt Instrument [Line Items]
Long-term debt, gross	317.6			0.0
Senior Notes \| 5.250% Senior notes due 2025
Debt Instrument [Line Items]
Long-term debt, gross	0.0			$ 300.0
Debt stated interest rate		5.25%		5.25%
Senior Notes \| 4.625% Senior notes due 2027
Debt Instrument [Line Items]
Long-term debt, gross	$ 400.0			$ 400.0
Debt stated interest rate	4.625%
Senior Notes \| 4.375% Senior notes due 2031
Debt Instrument [Line Items]
Long-term debt, gross	$ 550.0			550.0
Debt stated interest rate	4.375%
Senior Notes \| 3.875% Senior notes due 2029
Debt Instrument [Line Items]
Long-term debt, gross	$ 800.0			$ 0.0
Debt stated interest rate	3.875%		3.875%