Other Comprehensive Income (Loss), Before Reclassification [Abstract]

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Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Reclassification Adjustment from AOCI, Realized upon Sale or Liquidation Discontinued Operations, Net of Tax

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Reclassification from AOCI, Current Period [Abstract]

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Amount before tax and reclassification adjustments of other comprehensive income (loss) attributable to parent.

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Amount of tax expense (benefit) allocated to other comprehensive income (loss) before reclassification adjustment from accumulated other comprehensive income (loss).

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Amount after tax of reclassification adjustment from accumulated other comprehensive income for translation gain (loss) realized upon the sale or liquidation of an investment in a foreign entity and foreign currency hedges that are designated and qualified as hedging instruments for hedges of the foreign currency exposure of a net investment in a foreign operation.

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ACCUMULATED OTHER COMPREHENSIVE INCOME (LOSS) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Increase (Decrease) in AOCI
Beginning balance	$ 2,004.5	$ 1,754.0	$ 1,825.2	$ 1,449.6
Other comprehensive income (loss) before reclassifications:
Pre-tax			51.6	14.4
Tax effect			(26.1)	(4.9)
Amount reclassified from accumulated other comprehensive income (loss):
Cumulative foreign currency translation adjustments associated with the Brazil Disposal	122.8	0.0	122.8	0.0
Other cumulative foreign currency translation adjustments	1.5	0.0	1.5	0.0
Benefit for income taxes			(0.5)	(2.6)
OTHER COMPREHENSIVE INCOME (LOSS), NET OF TAX	123.5	(10.2)	151.5	17.9
Ending balance	2,214.1	1,918.6	2,214.1	1,918.6
Floorplan interest expense (pre-tax)
Amount reclassified from accumulated other comprehensive income (loss):
Pre-tax			1.4	5.0
Other interest expense, net (pre-tax)
Amount reclassified from accumulated other comprehensive income (loss):
Pre-tax			0.7	2.9
Reclassification related to de-designated interest rate swaps (pre-tax)
Amount reclassified from accumulated other comprehensive income (loss):
Pre-tax				3.1
Accumulated other comprehensive income (loss)
Increase (Decrease) in AOCI
Beginning balance	(128.3)	(155.9)	(156.2)	(184.0)
Amount reclassified from accumulated other comprehensive income (loss):
OTHER COMPREHENSIVE INCOME (LOSS), NET OF TAX	123.5	(10.2)	151.5	17.9
Ending balance	(4.7)	(166.1)	(4.7)	(166.1)
Accumulated Income (Loss) On Foreign Currency Translation
Increase (Decrease) in AOCI
Beginning balance			(158.2)	(151.6)
Other comprehensive income (loss) before reclassifications:
Pre-tax			(59.3)	(6.7)
Tax effect			0.0	0.0
Amount reclassified from accumulated other comprehensive income (loss):
Cumulative foreign currency translation adjustments associated with the Brazil Disposal			122.8
Other cumulative foreign currency translation adjustments			1.5
Benefit for income taxes			0.0	0.0
OTHER COMPREHENSIVE INCOME (LOSS), NET OF TAX			65.1	(6.7)
Ending balance	(93.1)	(158.2)	(93.1)	(158.2)
Accumulated Income (Loss) On Foreign Currency Translation \| Floorplan interest expense (pre-tax)
Amount reclassified from accumulated other comprehensive income (loss):
Pre-tax			0.0	0.0
Accumulated Income (Loss) On Foreign Currency Translation \| Other interest expense, net (pre-tax)
Amount reclassified from accumulated other comprehensive income (loss):
Pre-tax			0.0	0.0
Accumulated Income (Loss) On Foreign Currency Translation \| Reclassification related to de-designated interest rate swaps (pre-tax)
Amount reclassified from accumulated other comprehensive income (loss):
Pre-tax				0.0
Accumulated Income (Loss) On Interest Rate Swaps
Increase (Decrease) in AOCI
Beginning balance			2.0	(32.5)
Other comprehensive income (loss) before reclassifications:
Pre-tax			110.9	21.0
Tax effect			(26.1)	(4.9)
Amount reclassified from accumulated other comprehensive income (loss):
Cumulative foreign currency translation adjustments associated with the Brazil Disposal			0.0
Other cumulative foreign currency translation adjustments			0.0
Benefit for income taxes			(0.5)	(2.6)
OTHER COMPREHENSIVE INCOME (LOSS), NET OF TAX			86.4	24.5
Ending balance	$ 88.4	$ (7.9)	88.4	(7.9)
Accumulated Income (Loss) On Interest Rate Swaps \| Floorplan interest expense (pre-tax)
Amount reclassified from accumulated other comprehensive income (loss):
Pre-tax			1.4	5.0
Accumulated Income (Loss) On Interest Rate Swaps \| Other interest expense, net (pre-tax)
Amount reclassified from accumulated other comprehensive income (loss):
Pre-tax			$ 0.7	2.9
Accumulated Income (Loss) On Interest Rate Swaps \| Reclassification related to de-designated interest rate swaps (pre-tax)
Amount reclassified from accumulated other comprehensive income (loss):
Pre-tax				$ 3.1