Auto Loans Receivable - Components Of Receivables, Net Of Allowances For Expected Credit Losses (Details) - USD ($) $ in Millions	Sep. 30, 2024	Dec. 31, 2023	Dec. 31, 2022
Receivables [Abstract]
Total auto loans receivable	$ 941.8	$ 451.2
Accrued interest and fees	7.5	4.8
Deferred loan origination costs	3.5	1.6
Less: unearned discounts	(6.3)	(8.9)
Less: allowances for expected credit losses	(55.0)	(46.3)	$ (57.5)
Auto loans receivable, net	$ 891.5	$ 402.4

Amount of allowance for credit loss on financing receivable, classified as noncurrent.

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- Definition

Amortized cost, before allowance for credit loss, fee, and loan in process, of financing receivable. Excludes financing receivable covered under loss sharing agreement and net investment in lease.

+ References

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- Definition

Amount of unamortized loan commitment, origination, and other costs (fees) on financing receivable recognized as adjustment to yield. Excludes financing receivable covered under loss sharing agreement.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 310
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-URI https://asc.fasb.org/1943274/2147481598/310-20-45-1

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- Definition

Amount of unamortized purchase premium (discount) on financing receivable. Excludes financing receivable covered under loss sharing agreement.

+ References

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- Definition

Carrying amount as of the balance sheet date of interest earned but not received. Also called accrued interest or accrued interest receivable.

+ References

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- Definition

Amortized cost, after allowance for credit loss, of financing receivable. Excludes financing receivable covered under loss sharing agreement and net investment in lease.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- References

No definition available.

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