Long Term Debt - Schedule of Aggregate Principal Balance and Fair Value of Finance Receivables Pledged to Securitization Debt (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Asset Pledged as Collateral without Right
Debt Instrument [Line Items]
Aggregate Principal Balance	$ 361,609	$ 84,477
Asset Pledged as Collateral with Right
Debt Instrument [Line Items]
Fair Value	316,998	77,904
United Auto Credit 2021-1 | Asset Pledged as Collateral without Right
Debt Instrument [Line Items]
Aggregate Principal Balance	38,951	84,477
United Auto Credit 2021-1 | Asset Pledged as Collateral with Right
Debt Instrument [Line Items]
Fair Value	35,790	$ 77,904
United Auto Credit 2022-2 | Asset Pledged as Collateral without Right
Debt Instrument [Line Items]
Aggregate Principal Balance	125,072
United Auto Credit 2022-2 | Asset Pledged as Collateral with Right
Debt Instrument [Line Items]
Fair Value	111,379
United Auto Credit 2023-1 | Asset Pledged as Collateral without Right
Debt Instrument [Line Items]
Aggregate Principal Balance	197,586
United Auto Credit 2023-1 | Asset Pledged as Collateral with Right
Debt Instrument [Line Items]
Fair Value	$ 169,829