Fair Value Measurement and Fair Value of Financial Instruments - Quantitative Information for Significant Unobservable Inputs (Details) - USD ($) $ in Thousands	Sep. 30, 2023	Dec. 31, 2022
Derivative Assets
Derivative assets - Fair value	$ 862,316	$ 755,328
Derivative Liabilities
Derivative liabilities - Fair value	948,387	887,264
Fair Value, Measurements, Recurring
Derivative Assets
Derivative assets - Fair value	862,316	755,328
Derivative Liabilities
Derivative liabilities - Fair value	948,387	887,264
Fair Value, Measurements, Nonrecurring
Derivative Liabilities
Loans held-for-investment, fair value disclosure	35,133	72,614
Fair Value, Measurements, Nonrecurring \| Tax credit investments
Derivative Liabilities
Assets, fair value disclosure	1,038
Level 3 \| Fair Value, Measurements, Recurring
Derivative Assets
Derivative assets - Fair value	352	323
Derivative Liabilities
Derivative liabilities - Fair value	15,119	0
Level 3 \| Fair Value, Measurements, Nonrecurring
Derivative Liabilities
Loans held-for-investment, fair value disclosure	35,133	72,614
Level 3 \| Fair Value, Measurements, Nonrecurring \| Tax credit investments
Derivative Liabilities
Assets, fair value disclosure	1,038
Level 3 \| Fair Value, Measurements, Nonrecurring \| Discounted cash flows
Derivative Liabilities
Loans held-for-investment, fair value disclosure		23,322
Level 3 \| Fair Value, Measurements, Nonrecurring \| Fair value of collateral
Derivative Liabilities
Loans held-for-investment, fair value disclosure	13,955	17,912
Level 3 \| Fair Value, Measurements, Nonrecurring \| Fair value of collateral
Derivative Liabilities
Loans held-for-investment, fair value disclosure	6,134
Level 3 \| Fair Value, Measurements, Nonrecurring \| Individual analysis of each investment \| Tax credit investments
Derivative Liabilities
Assets, fair value disclosure	1,038
Level 3 \| Fair Value, Measurements, Nonrecurring \| Fair value of property
Derivative Liabilities
Loans held-for-investment, fair value disclosure	$ 15,044	$ 31,380
Level 3 \| Fair Value, Measurements, Nonrecurring \| Selling cost \| Fair value of property
Derivative Liabilities
Loans held-for-investment, measurement input	8.00%	8.00%
Level 3 \| Fair Value, Measurements, Nonrecurring \| Minimum \| Discount \| Discounted cash flows
Derivative Liabilities
Loans held-for-investment, measurement input		4.00%
Level 3 \| Fair Value, Measurements, Nonrecurring \| Minimum \| Discount \| Fair value of collateral
Derivative Liabilities
Loans held-for-investment, measurement input	15.00%	15.00%
Level 3 \| Fair Value, Measurements, Nonrecurring \| Maximum \| Discount \| Discounted cash flows
Derivative Liabilities
Loans held-for-investment, measurement input		6.00%
Level 3 \| Fair Value, Measurements, Nonrecurring \| Maximum \| Discount \| Fair value of collateral
Derivative Liabilities
Loans held-for-investment, measurement input	75.00%	75.00%
Level 3 \| Fair Value, Measurements, Nonrecurring \| Weighted Average \| Discount \| Discounted cash flows
Derivative Liabilities
Loans held-for-investment, measurement input		4.00%
Level 3 \| Fair Value, Measurements, Nonrecurring \| Weighted Average \| Discount \| Fair value of collateral
Derivative Liabilities
Loans held-for-investment, measurement input	48.00%	37.00%
Level 3 \| Fair Value, Measurements, Nonrecurring \| Weighted Average \| Selling cost \| Fair value of property
Derivative Liabilities
Loans held-for-investment, measurement input	8.00%	8.00%
Equity contracts \| Fair Value, Measurements, Recurring
Derivative Assets
Derivative assets - Fair value	$ 352	$ 323
Derivative Liabilities
Derivative liabilities - Fair value	15,119
Equity contracts \| Level 3 \| Fair Value, Measurements, Recurring
Derivative Assets
Derivative assets - Fair value	352	$ 323
Derivative Liabilities
Derivative liabilities - Fair value	$ 15,119
Equity contracts \| Level 3 \| Fair Value, Measurements, Recurring \| Liquidity discount
Derivative Liabilities
Measurement input	47.00%	47.00%
Equity contracts \| Level 3 \| Fair Value, Measurements, Recurring \| Payout % designated based on operating revenue and operating EBITDA of investee
Derivative Liabilities
Measurement input	84.00%
Equity contracts \| Level 3 \| Fair Value, Measurements, Recurring \| Minimum \| Equity volatility \| Black-Scholes option pricing model
Derivative Liabilities
Measurement input	41.00%	42.00%
Equity contracts \| Level 3 \| Fair Value, Measurements, Recurring \| Maximum \| Equity volatility \| Black-Scholes option pricing model
Derivative Liabilities
Measurement input	51.00%	60.00%
Equity contracts \| Level 3 \| Fair Value, Measurements, Recurring \| Weighted Average \| Equity volatility \| Black-Scholes option pricing model
Derivative Liabilities
Measurement input	46.00%	54.00%
Equity contracts \| Level 3 \| Fair Value, Measurements, Recurring \| Weighted Average \| Liquidity discount
Derivative Liabilities
Measurement input	47.00%	47.00%
Equity contracts \| Level 3 \| Fair Value, Measurements, Recurring \| Weighted Average \| Payout % designated based on operating revenue and operating EBITDA of investee
Derivative Liabilities
Measurement input	84.00%

Equity Contracts, Measurement Input

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- Definition

Loans Receivable, Measurement Input

+ References

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- Definition

Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482106/820-10-50-2

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- Definition

Fair value, before effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets not subject to a master netting arrangement and elected not to be offset.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 320
-Name Accounting Standards Codification
-Section S99
-Paragraph 5C
-Subparagraph (SX 210.12-13C(Column F))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480032/946-320-S99-5C

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 320
-Name Accounting Standards Codification
-Section S99
-Paragraph 5B
-Subparagraph (SX 210.12-13B(Column E))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480032/946-320-S99-5B

Reference 3: http://www.xbrl.org/2003/role/exampleRef
-Topic 210
-SubTopic 20
-Name Accounting Standards Codification
-Section 55
-Paragraph 22
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483444/210-20-55-22

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 210
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483466/210-20-50-3

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- Definition

Fair value, before effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities not subject to a master netting arrangement and elected not to be offset.

+ References

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- Definition

Fair value portion of loan receivable, including, but not limited to, mortgage loans held for investment, finance receivables held for investment, policy loans on insurance contracts.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Publisher FASB
-URI https://asc.fasb.org//310-10/tableOfContent

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