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FLOOR PLAN NOTES PAYABLE—NON-TRADE - Narrative (Details) |  | 12 Months Ended |  |  |  |
--- | --- | --- | --- | --- | --- | ---
Oct. 20, 2023 | Dec. 31, 2024 USD ($) | Dec. 31, 2023 USD ($) | Sep. 30, 2023 USD ($) | Oct. 29, 2021 USD ($) | Oct. 16, 2014 USD ($)
Senior Notes |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Face amount |  |  |  | $ 250,000,000 |  |
2023 Senior Credit Facility |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Debt instrument, variable rate, minimum | 0.0100 |  |  |  |  |
2023 Senior Credit Facility | Minimum | Base Rate Component, Federal Funds |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Basis spread on variable rate | 0.50% |  |  |  |  |
2023 Senior Credit Facility | Minimum | Base Rate Component, SOFR |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Basis spread on variable rate | 1.00% |  |  |  |  |
2023 Senior Credit Facility | Minimum | SOFR |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Basis spread on variable rate | 1.00% |  |  |  |  |
2023 Senior Credit Facility | Minimum | Base Rate |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Basis spread on variable rate | 0.15% |  |  |  |  |
2023 Senior Credit Facility | Maximum | SOFR |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Basis spread on variable rate | 2.00% |  |  |  |  |
2023 Senior Credit Facility | Maximum | Base Rate |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Basis spread on variable rate | 1.00% |  |  |  |  |
New Vehicle Floor Plan Facility | SOFR |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Basis spread on variable rate | 1.10% |  |  |  |  |
New Vehicle Floor Plan Facility | Base Rate |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Basis spread on variable rate | 0.10% |  |  |  |  |
Used Vehicle Floor Plan Facility | SOFR |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Basis spread on variable rate | 1.40% |  |  |  |  |
Used Vehicle Floor Plan Facility | Base Rate |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Basis spread on variable rate | 0.40% |  |  |  |  |
Revolving Credit Facility1 | Minimum | Line of Credit |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Commitment fee percentage |  | 0.15% |  |  |  |
Revolving Credit Facility1 | Maximum | Line of Credit |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Commitment fee percentage |  | 0.40% |  |  |  |
New Vehicle and Used Vehicle Floor Plan | Line of Credit |  |  |  |  |  |
Debt Disclosure [Abstract] |  |  |  |  |  |
Unused capacity, commitment fee percentage |  | 0.15% |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Unused capacity, commitment fee percentage |  | 0.15% |  |  |  |
Loaner Vehicle Notes Payable - Bank of America |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Notes Payable |  | $ 56,700,000 | $ 127,200,000 |  |  |
Loaner Vehicle Notes Payable - OEMs |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Notes Payable |  | $ 161,500,000 | $ 111,900,000 |  |  |
Revolving Credit Facility | 2019 Senior Credit Facility | Bank of America |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Aggregate commitments |  |  |  |  | $ 500,000,000 |
New Vehicle Revolving Floor Plan Facility | 2019 Senior Credit Facility | Bank of America |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Aggregate commitments |  |  |  |  | 1,930,000,000 |
Used Vehicle Revolving Floor Plan Facility |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Commitment fee percentage |  | 0.15% |  |  |  |
Used Vehicle Revolving Floor Plan Facility | 2019 Senior Credit Facility | Bank of America |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Aggregate commitments |  |  |  |  | $ 375,000,000 |
Senior Credit Facility | 2019 Senior Credit Facility |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Maximum borrowing capacity |  | $ 750,000,000.0 |  |  |  |
Standby Letters of Credit | Bank of America |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Face amount |  | $ 50,000,000.0 |  |  |  | $ 50,000,000.0

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