Fair Value Measurements - Narrative (Details) $ in Thousands	12 Months Ended
Dec. 31, 2023 USD ($)	Dec. 31, 2022 USD ($)
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Trading investments	$ 54,481	$ 55,903
Vertical risk retention, amount	$ 54,000	$ 51,000
Vertical risk retention interest	5.00%	5.00%
Gain (loss) debt securities	$ 3,000	$ (1,000)
Gain (loss) on investment	4,000	13,000
Debt Securities, Trading
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Settlement debt securities	1,000	13,000
Level 3
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Trading investments	$ 54,000	$ 56,000
Minimum \| Measurement Input CPR Rate
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Measurement input	0.081
Minimum \| Measurement Input, Default Rate
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Measurement input		0.051
Maximum \| Measurement Input CPR Rate
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Measurement input	0.122
Maximum \| Measurement Input, Default Rate
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Measurement input		0.207
Weighted Average \| Measurement Input CPR Rate
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Measurement input	0.0949
Weighted Average \| Measurement Input, Default Rate
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Measurement input		0.1103
Convertible Debt Securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Trading investments		$ 5,000
Interest income, debt securities, trading	$ 1,000	$ 1,000

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Vertical Risk Retention, Percentage

+ References

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- Definition

Amount of unrealized and realized gain (loss) on investment in debt security measured at fair value with change in fair value recognized in net income (trading).

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 14
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481800/320-10-50-14

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Value of input used to measure investment in debt security measured at fair value with change in fair value recognized in net income (trading).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (bbb)(2)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482106/820-10-50-2

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+ References

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Amount of settlement of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition

Amount of realized and unrealized gain (loss) on investment.

+ References

Reference 1: http://www.xbrl.org/2003/role/recommendedDisclosureRef
-Topic 230
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
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Amount of interest income, amortization of premium and accretion of discount, on investment in debt security measured at fair value with change in fair value recognized in net income (trading); classified as operating.

+ References

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Amount of investment in debt security measured at fair value with change in fair value recognized in net income (trading).

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481830/320-10-45-1

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 210
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