Significant Accounting Policies (Policies)	3 Months Ended
Mar. 31, 2024
Accounting Policies [Abstract]
Adoption of New Accounting Standards [Policy Text Block]	A. Adoption of New Accounting Standards In March 2020, the FASB issued ASU 2020-04, Reference Rate Reform (Topic 848): Facilitation of the Effects of Reference Rate Reform on Financial Reporting. Certain aspects of this topic were later enhanced and clarified in January 2021 when the FASB issued ASU 2021-01, Reference Rate Reform (Topic 848). These ASUs provide temporary optional guidance to ease the burden in accounting for reference rate reform by providing optional expedients and exceptions for applying generally accepted accounting principles to contract modifications and hedging relationships, subject to meeting certain criteria, that reference the London Interbank Offer Rate ("LIBOR") or another reference rate expected to be discontinued. These ASUs are intended to help stakeholders during the global market-wide reference rate transition period and were to be in effect for a limited time through December 31, 2022. In December 2022, FASB issued ASU 2022-06 (Topic 848) and deferred the sunset date from December 31, 2022 to December 31, 2024. The Company’s adoption of the provisions of ASU 2020-04 and ASU 2021-01, effective March 12, 2020, was on a prospective basis. The adoption of these ASUs did not have a material impact on the Company's consolidated financial statements. See note 20. In March 2022, the FASB issued ASU 2022-02, Financial Instruments—Credit Losses (Topic 326): Troubled Debt Restructurings ("TDRs") and Vintage Disclosures. The amendments in this ASU eliminate TDR recognition and measurement guidance and instead, require that an entity evaluate (consistent with the accounting for other loan modifications) whether the modification represents a new loan or a continuation of an existing loan. The amendments also enhance existing disclosure requirements and introduce new requirements related to certain modifications of receivables made to borrowers experiencing financial difficulty. The Company's adoption of the provisions of ASU 2022-02, effective January 1, 2023, did not have an effect on the Company’s consolidated financial statements. In August 2020, the FASB issued ASU 2020-06, Debt—Debt with Conversion and Other Options (Subtopic 470-20) and Derivatives and Hedging—Contracts in Entity's Own Equity (Subtopic 815-40): Accounting for Convertible Instruments and Contracts in an Entity's Own Equity. This ASU simplifies accounting for convertible instruments by removing major separation models currently required. The ASU removes certain settlement conditions that are required for equity contracts to qualify for the derivative scope exception. The ASU also simplifies the diluted earnings per share (EPS) calculation in certain areas. The Company's adoption of the provisions of ASU 2020-06, effective January 1, 2024, did not have an effect on the Company’s consolidated financial statements. In June 2022, the FASB issued ASU 2022-03, Fair Value Measurement (Topic 820): Fair Value Measurement of Equity Securities Subject to Contractual Sale Restrictions. The amendments clarify that a contractual restriction on the sale of an equity security is not considered part of the unit of account of the equity security and, therefore, is not considered in measuring fair value. Early adoption is permitted. The Company's adoption of the provisions of ASU 2022-03, effective January 1, 2024, did not have an effect on the Company’s consolidated financial statements. In March 2023, the FASB issued ASU 2023-02, Investments—Equity Method and Joint Ventures (Topic 323): Accounting for Investments in Tax Credit Structures Using the Proportional Amortization Method. These amendments allow reporting entities to elect to account for qualifying tax equity investments using the proportional amortization method, regardless of the program giving rise to the related income tax credits. The ASU responds to stakeholder feedback that the proportional amortization method provides investors and other allocators of capital with a better understanding of the returns from investments that are made primarily for the purpose of receiving income tax credits and other income tax benefits. Early adoption is permitted. The Company's adoption of the provisions of ASU 2032-02, effective January 1, 2024, did not have an effect on the Company’s consolidated financial statements.
New Accounting Pronouncements, Policy [Policy Text Block]	B. Recent Accounting Developments In August 2023, the FASB issued ASU 2023-05, Business Combinations— Joint Venture Formations (Subtopic 805-60): Recognition and Initial Measurement. The ASU applies to the formation of entities that meet the definition of a joint venture (or a corporate joint venture) as defined in the FASB Accounting Standards Codification Master Glossary. The amendments in the ASU require that a joint venture apply a new basis of accounting upon formation. As a result, a newly formed joint venture, upon formation, would initially measure its assets and liabilities at fair value. The ASU is effective on a prospective basis for all joint ventures with a formation date on or after January 1, 2025. Early adoption of ASU No. 2023-05 is permitted in any interim or annual period in which financial statements have not yet been issued. The Company is currently evaluating the new guidance to determine the impact it may have on its consolidated financial statements. In October 2023, the FASB issued ASU 2023-06, Disclosure Improvements—Codification Amendments in Response to the Securities and Exchange Commission (“SEC’”) Disclosure Update and Simplification Initiative. These amendments clarify or improve disclosure and presentation requirements of a variety of topics and align the requirements in the FASB accounting standard codification with the SEC’s regulations. The ASU will be effective on the date the related disclosure requirements are removed from Regulation S-X or Regulation S-K by the SEC and will no longer be effective if the SEC has not removed the applicable disclosure requirement by June 30, 2027. Early adoption is not permitted. The Company is currently evaluating the new guidance to determine the impact it may have on its consolidated financial statements. In November 2023, the FASB issued ASU 2023-07, Segment Reporting (Topic 280): Improvements to Reportable Segment Disclosures. The amendments in this ASU are designed to improve reportable segment disclosure requirements primarily through enhanced disclosures about significant segment expenses. The ASU is effective for fiscal years beginning after December 15, 2023, and interim periods within fiscal years beginning after December 15, 2024. Early adoption is permitted. The Company is currently evaluating the new guidance to determine the impact it may have on its consolidated financial statements. In December 2023, the FASB issued ASU 2023-09, Income Taxes (Topic 740). The amendments in this ASU address investor requests for more transparency about income tax information through improvements to income tax disclosures primarily related to the rate reconciliation and income taxes paid information. The amendments in this ASU are effective for annual periods beginning after December 15, 2024 and should be applied on a prospective basis. Retrospective application is permitted. The Company is currently evaluating the new guidance to determine the impact it may have on its consolidated financial statements. In March 2024, the FASB issued ASU 2024-01, Compensation—Stock Compensation (Topic 718): Scope Application of Profits Interest and Similar Awards. The ASU provides an illustrative example intended to demonstrate how entities that account for profits interest and similar awards would determine whether a profits interest award should be accounted for as share-based payment arrangements in accordance with FASB Accounting Standards Codification (FASB ASC) 718, Compensation-Stock Compensation. The ASU is effective for public business entities for annual periods beginning after December 15, 2024 and interim periods with those annual periods. The Company is currently evaluating the new guidance to determine the impact it may have on its consolidated financial statements. In March 2024, the FASB issued ASU 2024-02, Codification Improvements — Amendments to Remove References to the Concepts Statements. The ASU amends the Codification to remove references to various concepts statements. In most instances, the references are extraneous and not required to understand or apply the guidance. In other instances, the references were used in prior Statements to provide guidance in certain topical areas. The ASU is effective for public business entities for annual periods beginning after December 15, 2024. The Company is currently evaluating the new guidance to determine the impact it may have on its consolidated financial statements.
Fair Value of Financial Instruments, Policy [Policy Text Block]	C. Fair Value of Financial Instruments The following methods and assumptions were used by the Company in estimating the fair value of its financial instruments. These determinations were based on available market information and appropriate valuation methodologies. Considerable judgment is required to interpret market data to develop the estimates and, therefore, these estimates may not necessarily be indicative of the amount the Company could realize in a current market exchange. The use of different market assumptions and/or estimation methodologies may have a material effect on the estimated fair value amounts. Refer to note 8 for a discussion of the valuation hierarchy with respect to investments-trading; other investments, at fair value; other investments sold, not yet purchased; and derivatives held by the Company. Cash and cash equivalents: Cash and cash equivalents are carried at historical cost, which is assumed to approximate fair value. The estimated fair value measurement of cash and cash equivalents is classified within level 1 of the valuation hierarchy. Investments-trading: These amounts are carried at fair value. The fair value is based on quoted market prices of an active exchange, independent broker market quotations, market price quotations from third- party pricing services, or valuation models when quotations are not available. Other investments, at fair value: These amounts are carried at fair value. The fair value is based on quoted market prices of an active exchange, independent broker market quotations, or valuation models when quotations are not available. In the case of investments in alternative investment funds, fair value is generally based on the reported net asset value of the underlying fund. Receivables under resale agreements: Receivables under resale agreements are carried at their contracted resale price, have short-term maturities, and are repriced frequently or bear market interest rates and, accordingly, these contracts are at amounts that approximate fair value. The estimated fair value measurements of receivables under resale agreements are based on observations of actual market activity and are generally classified within level 2 of the valuation hierarchy. Trading securities sold, not yet purchased: These amounts are carried at fair value. The fair value is based on quoted market prices of an active exchange, independent market quotations, market price quotations from third party pricing services, or valuation models when quotations are not available. Other investments sold, not yet purchased: These amounts are carried at fair value. The fair value is based on quoted market prices of an active exchange, independent broker market quotations, or valuation models when quotations are not available. Securities sold under agreements to repurchase: The liabilities for securities sold under agreements to repurchase are carried at their contracted repurchase price, have short-term maturities, and are repriced frequently or bear market interest rates and, accordingly, these contracts are carried at amounts that approximate fair value. The estimated fair value measurements of securities sold under agreements to repurchase are based on observations of actual market activity and are generally classified within level 2 of the valuation hierarchy. Redeemable financial instruments: The liabilities for redeemable financial instruments are carried at their redemption value, which approximates fair value. The estimated fair value measurement of the redeemable financial instruments is classified within level 3 of the valuation hierarchy. Debt: These amounts are carried at outstanding principal less unamortized discount and deferred financing costs. However, a substantial portion of the Company's debt was assumed in the AFN Merger and recorded at fair value as of that date. As of March 31, 2024 and December 31, 2023, the fair value of the Company’s debt was estimated to be $38,824 and $37,474, respectively. The estimated fair value measurements of the debt are generally based on discounted cash flow models prepared by the Company’s management primarily using discount rates for similar instruments issued to companies with similar credit risks to the Company and are generally classified within level 3 of the value hierarchy. Derivatives: These amounts are carried at fair value. Derivatives may be included as a component of investments-trading; trading securities sold, not yet purchased; other investments, at fair value; and other investments, sold not yet purchased. The fair value is generally based on quoted market prices on an exchange that is deemed to be active for derivative instruments such as foreign currency forward contracts and Eurodollar futures. For derivative instruments, such as TBAs and other extended settlement trades, the fair value is generally based on market price quotations from third party pricing services.

Significant Accounting Policies (Policies)

3 Months Ended

Mar. 31, 2024

Adoption of New Accounting Standards [Policy Text Block]

A. Adoption of New Accounting Standards

In March 2020, the FASB issued ASU 2020-04, Reference Rate Reform (Topic 848): Facilitation of the Effects of Reference Rate Reform on Financial Reporting. Certain aspects of this topic were later enhanced and clarified in January 2021 when the FASB issued ASU 2021-01, Reference Rate Reform (Topic 848). These ASUs provide temporary optional guidance to ease the burden in accounting for reference rate reform by providing optional expedients and exceptions for applying generally accepted accounting principles to contract modifications and hedging relationships, subject to meeting certain criteria, that reference the London Interbank Offer Rate ("LIBOR") or another reference rate expected to be discontinued. These ASUs are intended to help stakeholders during the global market-wide reference rate transition period and were to be in effect for a limited time through December 31, 2022. In December 2022, FASB issued ASU 2022-06 (Topic 848) and deferred the sunset date from December 31, 2022 to December 31, 2024. The Company’s adoption of the provisions of ASU 2020-04 and ASU 2021-01, effective March 12, 2020, was on a prospective basis. The adoption of these ASUs did not have a material impact on the Company's consolidated financial statements. See note 20.

In March 2022, the FASB issued ASU 2022-02, Financial Instruments—Credit Losses (Topic 326): Troubled Debt Restructurings ("TDRs") and Vintage Disclosures. The amendments in this ASU eliminate TDR recognition and measurement guidance and instead, require that an entity evaluate (consistent with the accounting for other loan modifications) whether the modification represents a new loan or a continuation of an existing loan. The amendments also enhance existing disclosure requirements and introduce new requirements related to certain modifications of receivables made to borrowers experiencing financial difficulty. The Company's adoption of the provisions of ASU 2022-02, effective January 1, 2023, did not have an effect on the Company’s consolidated financial statements.

In August 2020, the FASB issued ASU 2020-06, Debt—Debt with Conversion and Other Options (Subtopic 470-20) and Derivatives and Hedging—Contracts in Entity's Own Equity (Subtopic 815-40): Accounting for Convertible Instruments and Contracts in an Entity's Own Equity. This ASU simplifies accounting for convertible instruments by removing major separation models currently required. The ASU removes certain settlement conditions that are required for equity contracts to qualify for the derivative scope exception. The ASU also simplifies the diluted earnings per share (EPS) calculation in certain areas. The Company's adoption of the provisions of ASU 2020-06, effective January 1, 2024, did not have an effect on the Company’s consolidated financial statements.

In June 2022, the FASB issued ASU 2022-03, Fair Value Measurement (Topic 820): Fair Value Measurement of Equity Securities Subject to Contractual Sale Restrictions. The amendments clarify that a contractual restriction on the sale of an equity security is not considered part of the unit of account of the equity security and, therefore, is not considered in measuring fair value. Early adoption is permitted. The Company's adoption of the provisions of ASU 2022-03, effective January 1, 2024, did not have an effect on the Company’s consolidated financial statements.

In March 2023, the FASB issued ASU 2023-02, Investments—Equity Method and Joint Ventures (Topic 323): Accounting for Investments in Tax Credit Structures Using the Proportional Amortization Method. These amendments allow reporting entities to elect to account for qualifying tax equity investments using the proportional amortization method, regardless of the program giving rise to the related income tax credits. The ASU responds to stakeholder feedback that the proportional amortization method provides investors and other allocators of capital with a better understanding of the returns from investments that are made primarily for the purpose of receiving income tax credits and other income tax benefits. Early adoption is permitted. The Company's adoption of the provisions of ASU 2032-02, effective January 1, 2024, did not have an effect on the Company’s consolidated financial statements.

New Accounting Pronouncements, Policy [Policy Text Block]

B. Recent Accounting Developments

In August 2023, the FASB issued ASU 2023-05, Business Combinations— Joint Venture Formations (Subtopic 805-60): Recognition and Initial Measurement. The ASU applies to the formation of entities that meet the definition of a joint venture (or a corporate joint venture) as defined in the FASB Accounting Standards Codification Master Glossary. The amendments in the ASU require that a joint venture apply a new basis of accounting upon formation. As a result, a newly formed joint venture, upon formation, would initially measure its assets and liabilities at fair value. The ASU is effective on a prospective basis for all joint ventures with a formation date on or after January 1, 2025. Early adoption of ASU No. 2023-05 is permitted in any interim or annual period in which financial statements have not yet been issued. The Company is currently evaluating the new guidance to determine the impact it may have on its consolidated financial statements.

In October 2023, the FASB issued ASU 2023-06, Disclosure Improvements—Codification Amendments in Response to the Securities and Exchange Commission (“SEC’”) Disclosure Update and Simplification Initiative. These amendments clarify or improve disclosure and presentation requirements of a variety of topics and align the requirements in the FASB accounting standard codification with the SEC’s regulations. The ASU will be effective on the date the related disclosure requirements are removed from Regulation S-X or Regulation S-K by the SEC and will no longer be effective if the SEC has not removed the applicable disclosure requirement by June 30, 2027. Early adoption is not permitted. The Company is currently evaluating the new guidance to determine the impact it may have on its consolidated financial statements.

In November 2023, the FASB issued ASU 2023-07, Segment Reporting (Topic 280): Improvements to Reportable Segment Disclosures. The amendments in this ASU are designed to improve reportable segment disclosure requirements primarily through enhanced disclosures about significant segment expenses. The ASU is effective for fiscal years beginning after December 15, 2023, and interim periods within fiscal years beginning after December 15, 2024. Early adoption is permitted. The Company is currently evaluating the new guidance to determine the impact it may have on its consolidated financial statements.

In December 2023, the FASB issued ASU 2023-09, Income Taxes (Topic 740). The amendments in this ASU address investor requests for more transparency about income tax information through improvements to income tax disclosures primarily related to the rate reconciliation and income taxes paid information. The amendments in this ASU are effective for annual periods beginning after December 15, 2024 and should be applied on a prospective basis. Retrospective application is permitted. The Company is currently evaluating the new guidance to determine the impact it may have on its consolidated financial statements.

In March 2024, the FASB issued ASU 2024-01, Compensation—Stock Compensation (Topic 718): Scope Application of Profits Interest and Similar Awards. The ASU provides an illustrative example intended to demonstrate how entities that account for profits interest and similar awards would determine whether a profits interest award should be accounted for as share-based payment arrangements in accordance with FASB Accounting Standards Codification (FASB ASC) 718, Compensation-Stock Compensation. The ASU is effective for public business entities for annual periods beginning after December 15, 2024 and interim periods with those annual periods. The Company is currently evaluating the new guidance to determine the impact it may have on its consolidated financial statements.

In March 2024, the FASB issued ASU 2024-02, Codification Improvements — Amendments to Remove References to the Concepts Statements. The ASU amends the Codification to remove references to various concepts statements. In most instances, the references are extraneous and not required to understand or apply the guidance. In other instances, the references were used in prior Statements to provide guidance in certain topical areas. The ASU is effective for public business entities for annual periods beginning after December 15, 2024. The Company is currently evaluating the new guidance to determine the impact it may have on its consolidated financial statements.

Fair Value of Financial Instruments, Policy [Policy Text Block]

C. Fair Value of Financial Instruments

The following methods and assumptions were used by the Company in estimating the fair value of its financial instruments. These determinations were based on available market information and appropriate valuation methodologies. Considerable judgment is required to interpret market data to develop the estimates and, therefore, these estimates may not necessarily be indicative of the amount the Company could realize in a current market exchange. The use of different market assumptions and/or estimation methodologies may have a material effect on the estimated fair value amounts. Refer to note 8 for a discussion of the valuation hierarchy with respect to investments-trading; other investments, at fair value; other investments sold, not yet purchased; and derivatives held by the Company.

Cash and cash equivalents: Cash and cash equivalents are carried at historical cost, which is assumed to approximate fair value. The estimated fair value measurement of cash and cash equivalents is classified within level 1 of the valuation hierarchy.

Investments-trading: These amounts are carried at fair value. The fair value is based on quoted market prices of an active exchange, independent broker market quotations, market price quotations from third- party pricing services, or valuation models when quotations are not available.

Other investments, at fair value: These amounts are carried at fair value. The fair value is based on quoted market prices of an active exchange, independent broker market quotations, or valuation models when quotations are not available. In the case of investments in alternative investment funds, fair value is generally based on the reported net asset value of the underlying fund.

Receivables under resale agreements: Receivables under resale agreements are carried at their contracted resale price, have short-term maturities, and are repriced frequently or bear market interest rates and, accordingly, these contracts are at amounts that approximate fair value. The estimated fair value measurements of receivables under resale agreements are based on observations of actual market activity and are generally classified within level 2 of the valuation hierarchy.

Trading securities sold, not yet purchased: These amounts are carried at fair value. The fair value is based on quoted market prices of an active exchange, independent market quotations, market price quotations from third party pricing services, or valuation models when quotations are not available.

Other investments sold, not yet purchased: These amounts are carried at fair value. The fair value is based on quoted market prices of an active exchange, independent broker market quotations, or valuation models when quotations are not available.

Securities sold under agreements to repurchase: The liabilities for securities sold under agreements to repurchase are carried at their contracted repurchase price, have short-term maturities, and are repriced frequently or bear market interest rates and, accordingly, these contracts are carried at amounts that approximate fair value. The estimated fair value measurements of securities sold under agreements to repurchase are based on observations of actual market activity and are generally classified within level 2 of the valuation hierarchy.

Redeemable financial instruments: The liabilities for redeemable financial instruments are carried at their redemption value, which approximates fair value. The estimated fair value measurement of the redeemable financial instruments is classified within level 3 of the valuation hierarchy.

Debt: These amounts are carried at outstanding principal less unamortized discount and deferred financing costs. However, a substantial portion of the Company's debt was assumed in the AFN Merger and recorded at fair value as of that date. As of March 31, 2024 and December 31, 2023, the fair value of the Company’s debt was estimated to be $38,824 and $37,474, respectively. The estimated fair value measurements of the debt are generally based on discounted cash flow models prepared by the Company’s management primarily using discount rates for similar instruments issued to companies with similar credit risks to the Company and are generally classified within level 3 of the value hierarchy.

Derivatives: These amounts are carried at fair value. Derivatives may be included as a component of investments-trading; trading securities sold, not yet purchased; other investments, at fair value; and other investments, sold not yet purchased. The fair value is generally based on quoted market prices on an exchange that is deemed to be active for derivative instruments such as foreign currency forward contracts and Eurodollar futures. For derivative instruments, such as TBAs and other extended settlement trades, the fair value is generally based on market price quotations from third party pricing services.