Fair Value Measurement - Narrative (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Notes receivable and residual certificates	$ 6,181	$ 8,288
Average effect of fair value of hypothetical 20% adverse change in expected credit loss rates	(27.00%)
Fair Value, Inputs, Level 3
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Loans held-for-sale	$ 882,800	142,700
Loans held-for-investment	127,600	109,800
Notes receivable and residual certificates	$ 6,181	$ 8,288
Fair Value, Inputs, Level 3 | Notes Receivable
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Average effect on fair value of a 100 basis point increase in discount rates	(1.10%)	(0.69%)
Average effect on fair value of a 200 basis point increase in discount rates	(2.18%)	(1.37%)
Fair Value, Inputs, Level 3 | Minimum | Discount rate | Valuation Technique, Discounted Cash Flow
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Trailing fees liability, measurement input	6.36%
Fair Value, Inputs, Level 3 | Minimum | Discount rate | Notes Receivable | Valuation Technique, Discounted Cash Flow
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Loan receivable, measurement input	8.42%	4.96%
Fair Value, Inputs, Level 3 | Minimum | Discount rate | Loans (at fair value) | Valuation Technique, Discounted Cash Flow
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Loan receivable, measurement input	6.36%	3.42%
Fair Value, Inputs, Level 3 | Minimum | Credit risk rate | Valuation Technique, Discounted Cash Flow
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Trailing fees liability, measurement input	0.01%
Fair Value, Inputs, Level 3 | Minimum | Credit risk rate | Notes Receivable | Valuation Technique, Discounted Cash Flow
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Loan receivable, measurement input	0.59%	0.04%
Fair Value, Inputs, Level 3 | Minimum | Credit risk rate | Loans (at fair value) | Valuation Technique, Discounted Cash Flow
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Loan receivable, measurement input	0.01%	0.08%
Fair Value, Inputs, Level 3 | Maximum | Discount rate | Valuation Technique, Discounted Cash Flow
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Trailing fees liability, measurement input	22.28%
Fair Value, Inputs, Level 3 | Maximum | Discount rate | Notes Receivable | Valuation Technique, Discounted Cash Flow
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Loan receivable, measurement input	22.27%	15.72%
Fair Value, Inputs, Level 3 | Maximum | Discount rate | Loans (at fair value) | Valuation Technique, Discounted Cash Flow
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Loan receivable, measurement input	22.28%	16.49%
Fair Value, Inputs, Level 3 | Maximum | Credit risk rate | Valuation Technique, Discounted Cash Flow
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Trailing fees liability, measurement input	93.09%
Fair Value, Inputs, Level 3 | Maximum | Credit risk rate | Notes Receivable | Valuation Technique, Discounted Cash Flow
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Loan receivable, measurement input	50.69%	50.69%
Fair Value, Inputs, Level 3 | Maximum | Credit risk rate | Loans (at fair value) | Valuation Technique, Discounted Cash Flow
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Loan receivable, measurement input	93.09%	55.79%