FAIR VALUE MEASUREMENTS - Assets Measured at Fair Value on a Recurring Basis (Details) - USD ($) $ in Millions	Mar. 31, 2023	Dec. 31, 2022
4.625% Senior notes due 2027 \| Senior Notes
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Stated interest rate (percent)	4.625%
4.375% Senior notes due 2031 \| Senior Notes
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Stated interest rate (percent)	4.375%
3.875% Senior notes due 2029 \| Senior Notes
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Stated interest rate (percent)	3.875%
Fair Value, Recurring \| Carrying Value
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Shift Technologies, Inc.	$ 1.3	$ 1.8
Derivative assets	19.0	22.1
Derivative liabilities	19.0	22.1
Fair Value, Recurring \| Carrying Value \| Non-recourse notes payable \| Non-recourse
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Long-term debt	825.4	422.2
Fair Value, Recurring \| Carrying Value \| Real estate mortgages and other debt
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Long-term debt	488.9	489.0
Fair Value, Recurring \| 4.625% Senior notes due 2027 \| Carrying Value \| Senior Notes
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Long-term debt	400.0	400.0
Fair Value, Recurring \| 4.375% Senior notes due 2031 \| Carrying Value \| Senior Notes
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Long-term debt	550.0	550.0
Fair Value, Recurring \| 3.875% Senior notes due 2029 \| Carrying Value \| Senior Notes
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Long-term debt	800.0	800.0
Fair Value, Recurring \| Level 1 \| Estimate of Fair Value Measurement
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Shift Technologies, Inc.	1.3	1.8
Derivative assets	0.0	0.0
Derivative liabilities	0.0	0.0
Fair Value, Recurring \| Level 1 \| Estimate of Fair Value Measurement \| Non-recourse notes payable \| Non-recourse
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Long-term debt	0.0	0.0
Fair Value, Recurring \| Level 1 \| Estimate of Fair Value Measurement \| Real estate mortgages and other debt
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Long-term debt	0.0	0.0
Fair Value, Recurring \| Level 1 \| 4.625% Senior notes due 2027 \| Estimate of Fair Value Measurement \| Senior Notes
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Long-term debt	368.0	364.0
Fair Value, Recurring \| Level 1 \| 4.375% Senior notes due 2031 \| Estimate of Fair Value Measurement \| Senior Notes
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Long-term debt	460.6	448.3
Fair Value, Recurring \| Level 1 \| 3.875% Senior notes due 2029 \| Estimate of Fair Value Measurement \| Senior Notes
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Long-term debt	684.0	656.0
Fair Value, Recurring \| Level 2 \| Estimate of Fair Value Measurement
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Shift Technologies, Inc.	0.0	0.0
Derivative assets	19.0	22.1
Derivative liabilities	19.0	22.1
Fair Value, Recurring \| Level 2 \| Estimate of Fair Value Measurement \| Non-recourse notes payable \| Non-recourse
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Long-term debt	814.3	411.8
Fair Value, Recurring \| Level 2 \| Estimate of Fair Value Measurement \| Real estate mortgages and other debt
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Long-term debt	419.9	399.0
Fair Value, Recurring \| Level 2 \| 4.625% Senior notes due 2027 \| Estimate of Fair Value Measurement \| Senior Notes
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Long-term debt	0.0	0.0
Fair Value, Recurring \| Level 2 \| 4.375% Senior notes due 2031 \| Estimate of Fair Value Measurement \| Senior Notes
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Long-term debt	0.0	0.0
Fair Value, Recurring \| Level 2 \| 3.875% Senior notes due 2029 \| Estimate of Fair Value Measurement \| Senior Notes
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Long-term debt	0.0	0.0
Fair Value, Recurring \| Level 3 \| Estimate of Fair Value Measurement
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Shift Technologies, Inc.	0.0	0.0
Derivative assets	0.0	0.0
Derivative liabilities	0.0	0.0
Fair Value, Recurring \| Level 3 \| Estimate of Fair Value Measurement \| Non-recourse notes payable \| Non-recourse
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Long-term debt	0.0	0.0
Fair Value, Recurring \| Level 3 \| Estimate of Fair Value Measurement \| Real estate mortgages and other debt
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Long-term debt	0.0	0.0
Fair Value, Recurring \| Level 3 \| 4.625% Senior notes due 2027 \| Estimate of Fair Value Measurement \| Senior Notes
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Long-term debt	0.0	0.0
Fair Value, Recurring \| Level 3 \| 4.375% Senior notes due 2031 \| Estimate of Fair Value Measurement \| Senior Notes
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Long-term debt	0.0	0.0
Fair Value, Recurring \| Level 3 \| 3.875% Senior notes due 2029 \| Estimate of Fair Value Measurement \| Senior Notes
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Long-term debt	$ 0.0	$ 0.0

Contractual interest rate for funds borrowed, under the debt agreement.

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