Inventories and Floor Plan Payables - Floor Plan Payable (Details) - USD ($) $ in Thousands		1 Months Ended			12 Months Ended
	Oct. 01, 2021	Nov. 30, 2021	Jun. 30, 2020	May 31, 2020	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Sep. 30, 2021	Aug. 31, 2021	Jun. 30, 2021
Floor Plan Payable
Additional borrowings					$ 20,000	$ 0	$ 14,029
Floor Plan Facility
Floor Plan Payable
Period for temporary reduction in consolidated current ratio				4 months
Number of days into 2021 the notice can be given				7 days
Maximum borrowing capacity					$ 1,700,000	$ 1,379,750		$ 1,700,000	$ 1,380,000
Quarterly reduction in maximum borrowing capacity										$ 3,000
Increase in aggregate amount								50,000
Applicable interest rate (as a percent)					1.96%	2.20%
FLAIR offset account amount					$ 92,100	$ 133,600
Voluntary principal payment			$ 20,000
Additional borrowings		$ 20,000
Floor Plan Facility | Minimum
Floor Plan Payable
FLAIR Maximum Percentage					20.00%
Floor Plan Facility | Maximum
Floor Plan Payable
Increase in aggregate amount								200,000
FLAIR Maximum Percentage					35.00%
Floor Plan Facility | BSBY Rate | Minimum
Floor Plan Payable
Variable rate spread (as a percent)	1.90%
Floor Plan Facility | BSBY Rate | Maximum
Floor Plan Payable
Variable rate spread (as a percent)	2.50%
Floor Plan Facility | Base Rate | Minimum
Floor Plan Payable
Variable rate spread (as a percent)	0.40%
Floor Plan Facility | Base Rate | Maximum
Floor Plan Payable
Variable rate spread (as a percent)	1.00%
Letters of credit | Floor Plan Facility
Floor Plan Payable
Maximum borrowing capacity								30,000	15,000
Line of Credit | Floor Plan Facility
Floor Plan Payable
Maximum borrowing capacity					$ 70,000	$ 48,000		$ 70,000	$ 42,000
Applicable interest rate (as a percent)					2.31%	2.55%
Line of Credit | Floor Plan Facility | London Interbank Offered Rate (LIBOR)
Floor Plan Payable
Variable rate spread (as a percent)	2.40%
Line of Credit | Floor Plan Facility | BSBY Rate
Floor Plan Payable
Variable rate spread (as a percent)	2.25%
Line of Credit | Floor Plan Facility | BSBY Rate | In Case of BSBY Rate Loan
Floor Plan Payable
Variable rate spread (as a percent)	0.50%
Line of Credit | Floor Plan Facility | BSBY Rate | In Case of Base Rate Loan
Floor Plan Payable
Variable rate spread (as a percent)	1.75%
Line of Credit | Floor Plan Facility | Federal Funds Rate
Floor Plan Payable
Variable rate spread (as a percent)	0.75%