Inventory and Vehicle Floorplan Payable (Narrative) (Details) - USD ($) $ in Millions |
Jun. 30, 2026 |
Dec. 31, 2025 |
|---|---|---|
| Floorplan Payable [Line Items] | ||
| Service loaner and rental vehicle inventory | $ 495.5 | $ 455.4 |
| Vehicle floorplan facilities, amount outstanding | $ 4,058.9 | $ 3,828.3 |
| New Vehicle Floorplan Facilities | ||
| Floorplan Payable [Line Items] | ||
| Vehicle floorplan facilities, weighted-average interest rate (percent) | 5.10% | 5.40% |
| Vehicle floorplan facilities, maximum borrowing capacity | $ 4,800.0 | |
| Vehicle floorplan facilities, amount outstanding | $ 3,400.0 | |
| Used Vehicle Floorplan Facilities | ||
| Floorplan Payable [Line Items] | ||
| Vehicle floorplan facilities, weighted-average interest rate (percent) | 5.10% | 5.20% |
| Vehicle floorplan facilities, maximum borrowing capacity | $ 775.0 | |
| Vehicle floorplan facilities, amount outstanding | 670.8 | |
| Used vehicle floorplan facilities, unused borrowing capacity | 104.2 | |
| Used vehicle floorplan facilities, remaining borrowing capacity | $ 0.3 |