Fair Value Measurement and Fair Value of Financial Instruments - Quantitative Information for Significant Unobservable Inputs (Details) - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023
Derivative Assets
Derivative assets - Fair value	$ 622,238	$ 610,920
Derivative Liabilities
Derivative liabilities - Fair value	693,548	613,314
Fair Value, Measurements, Recurring
Derivative Assets
Derivative assets - Fair value	622,238	610,920
Derivative Liabilities
Derivative liabilities - Fair value	693,548	613,314
Fair Value, Measurements, Nonrecurring
Derivative Liabilities
Loans held-for-investment, fair value disclosure	48,294	45,892
Fair Value, Measurements, Nonrecurring \| Tax credit investments
Derivative Liabilities
Affordable housing partnership, tax credit and CRA investments, net		868
Level 3 \| Fair Value, Measurements, Recurring
Derivative Assets
Derivative assets - Fair value	330	336
Derivative Liabilities
Derivative liabilities - Fair value	15,119	15,119
Level 3 \| Fair Value, Measurements, Nonrecurring
Derivative Liabilities
Loans held-for-investment, fair value disclosure	48,294	45,892
Level 3 \| Fair Value, Measurements, Nonrecurring \| Tax credit investments
Derivative Liabilities
Affordable housing partnership, tax credit and CRA investments, net		868
Level 3 \| Fair Value, Measurements, Nonrecurring \| Fair value of collateral
Derivative Liabilities
Loans held-for-investment, fair value disclosure	6,917	16,328
Level 3 \| Fair Value, Measurements, Nonrecurring \| Fair value of collateral
Derivative Liabilities
Loans held-for-investment, fair value disclosure	8,471	3,009
Level 3 \| Fair Value, Measurements, Nonrecurring \| Individual analysis of each investment \| Tax credit investments
Derivative Liabilities
Affordable housing partnership, tax credit and CRA investments, net		868
Level 3 \| Fair Value, Measurements, Nonrecurring \| Fair value of property
Derivative Liabilities
Loans held-for-investment, fair value disclosure	$ 32,906	$ 26,555
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 \| Fair value of collateral
Derivative Liabilities
Loans held-for-investment, measurement input	20.00%	15.00%
Level 3 \| Fair Value, Measurements, Nonrecurring \| Maximum \| Discount \| Fair value of collateral
Derivative Liabilities
Loans held-for-investment, measurement input		75.00%
Level 3 \| Fair Value, Measurements, Nonrecurring \| Weighted Average \| Discount \| Fair value of collateral
Derivative Liabilities
Loans held-for-investment, measurement input	20.00%	45.00%
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	$ 330	$ 336
Derivative Liabilities
Derivative liabilities - Fair value	15,119	15,119
Equity contracts \| Level 3 \| Fair Value, Measurements, Recurring
Derivative Assets
Derivative assets - Fair value	330	336
Derivative Liabilities
Derivative liabilities - Fair value	$ 15,119	$ 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%	84.00%
Equity contracts \| Level 3 \| Fair Value, Measurements, Recurring \| Minimum \| Equity volatility \| Black-Scholes option pricing model
Derivative Liabilities
Measurement input	39.00%	37.00%
Equity contracts \| Level 3 \| Fair Value, Measurements, Recurring \| Maximum \| Equity volatility \| Black-Scholes option pricing model
Derivative Liabilities
Measurement input	50.00%	48.00%
Equity contracts \| Level 3 \| Fair Value, Measurements, Recurring \| Weighted Average \| Equity volatility \| Black-Scholes option pricing model
Derivative Liabilities
Measurement input	46.00%	45.00%
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%	84.00%

Equity Contracts, Measurement Input

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- Definition

Loans Receivable, Measurement Input

+ References

No definition available.

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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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- References

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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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