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SEGMENT INFORMATION - Schedule of Reportable Segment Information (Details) - USD ($) $ in Millions | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2025 | Sep. 30, 2024 | Sep. 30, 2025 | Sep. 30, 2024
Segment Reporting Information |  |  |  |
Total revenues | $ 5,782.7 | $ 5,221.4 | $ 16,991.5 | $ 14,388.3
Cost of sales | 4,863.0 | 4,368.7 | 14,244.1 | 12,026.5
SG&A expenses | 654.9 | 591.6 | 1,918.2 | 1,564.9
Depreciation and amortization expense | 31.6 | 29.5 | 89.6 | 81.6
Asset impairments | 123.9 | 0.0 | 124.6 | 0.0
Restructuring charges | 1.6 |  | 20.3 |
Floorplan interest expense | 23.7 | 31.1 | 77.0 | 76.3
Other interest expense, net | 48.0 | 39.8 | 130.4 | 102.5
Other segment items | 0.0 | 1.1 | (0.2) | 0.7
Income (loss) before income taxes | 36.2 | 159.6 | 387.5 | 535.8
Capital expenditures: | 68.2 | 49.7 | 192.2 | 152.6
Real estate related capital expenditures |  |  |  |
Segment Reporting Information |  |  |  |
Capital expenditures: | 10.0 | 0.0 | 42.5 | 21.0
Non-real estate related capital expenditures |  |  |  |
Segment Reporting Information |  |  |  |
Capital expenditures: | 58.2 | 49.7 | 149.6 | 131.6
U.S. |  |  |  |
Segment Reporting Information |  |  |  |
Total revenues | 4,277.9 | 3,971.1 | 12,376.9 | 11,538.0
Cost of sales | 3,562.9 | 3,293.0 | 10,258.2 | 9,553.1
SG&A expenses | 481.2 | 445.4 | 1,400.2 | 1,257.9
Depreciation and amortization expense | 23.8 | 21.8 | 67.0 | 65.8
Asset impairments | 0.0 |  | (1.9) |
Restructuring charges | 0.0 |  | 0.0 |
Floorplan interest expense | 17.1 | 24.8 | 57.9 | 63.9
Other interest expense, net | 40.8 | 34.5 | 108.0 | 92.4
Other segment items | 0.0 | 0.0 | (0.2) | 0.0
Income (loss) before income taxes | 152.2 | 151.7 | 487.9 | 504.9
Capital expenditures: | 58.2 | 40.3 | 170.1 | 111.4
U.S. | Real estate related capital expenditures |  |  |  |
Segment Reporting Information |  |  |  |
Capital expenditures: | 10.0 | 0.0 | 42.5 | 3.2
U.S. | Non-real estate related capital expenditures |  |  |  |
Segment Reporting Information |  |  |  |
Capital expenditures: | 48.2 | 40.3 | 127.5 | 108.3
U.K. |  |  |  |
Segment Reporting Information |  |  |  |
Total revenues | 1,504.8 | 1,250.3 | 4,614.6 | 2,850.2
Cost of sales | 1,300.0 | 1,075.7 | 3,985.9 | 2,473.4
SG&A expenses | 173.7 | 146.1 | 518.1 | 307.0
Depreciation and amortization expense | 7.8 | 7.7 | 22.6 | 15.8
Asset impairments | 123.9 |  | 126.5 |
Restructuring charges | 1.6 |  | 20.3 |
Floorplan interest expense | 6.6 | 6.4 | 19.1 | 12.4
Other interest expense, net | 7.2 | 5.3 | 22.5 | 10.1
Other segment items | 0.0 | 1.1 | 0.0 | 0.7
Income (loss) before income taxes | (116.0) | 7.9 | (100.3) | 30.9
Capital expenditures: | 10.1 | 9.4 | 22.1 | 41.1
U.K. | Real estate related capital expenditures |  |  |  |
Segment Reporting Information |  |  |  |
Capital expenditures: | 0.0 | 0.0 | 0.0 | 17.8
U.K. | Non-real estate related capital expenditures |  |  |  |
Segment Reporting Information |  |  |  |
Capital expenditures: | $ 10.1 | $ 9.4 | $ 22.1 | $ 23.3

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