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Fair Value Measurement - Narrative (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Average effect of fair value of hypothetical 20% adverse change in expected credit loss rates (in percent)	17.00%
Fair Value, Inputs, Level 3
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Notes receivable and residual certificates	$ 16,033	$ 19,074
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 (in percent)	1.05%	1.23%
Average effect on fair value of a 200 basis point increase in discount rates (in percent)	2.08%	2.36%
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	0.0352
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	0.0021
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	0.1660
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	0.5231

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- Definition

Sensitivity Analysis of Fair Value, Assets, Impact of 100 Basis Point Increase In Discount Rates, Average

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Sensitivity Analysis of Fair Value, Assets, Impact of 20 Percent Adverse Change in Expected Credit Loss Rates, Average

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- Definition

Fair value portion of an agreement for an unconditional promise by the maker to pay the holder a definite sum of money at a future date.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.3(b))
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

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