New Accounting Pronouncements	9 Months Ended
Sep. 30, 2019
Accounting Policies [Abstract]
New accounting pronouncements	Basis of Presentation The accompanying condensed consolidated financial statements of the Company have been prepared pursuant to the rules and regulations of the U.S. Securities and Exchange Commission (the "SEC") regarding interim financial reporting. Accordingly, they do not include all of the information and notes required by accounting principles generally accepted in the United States of America ("U.S. GAAP") for complete financial statements and should be read in conjunction with the audited consolidated financial statements and notes thereto included in the Company's Annual Report on Form 10-K for the year ended December 31, 2018 (the "Form 10-K"). The accompanying condensed consolidated balance sheet data was derived from the audited consolidated financial statements, but does not include all disclosures required by U.S. GAAP for annual financial statement purposes. The accompanying condensed consolidated financial statements reflect all adjustments which are, in the opinion of management, necessary for a fair presentation of the financial position, results of operations and cash flows for the interim periods presented. Preparing financial statements requires management to make estimates and assumptions that affect the amounts that are reported in the financial statements and the accompanying disclosures. Although these estimates are based on management's knowledge of current events and actions that the Company may undertake in the future, actual results may differ materially from the estimates. The condensed consolidated results of operations for the nine month period ended September 30, 2019 are not necessarily indicative of the results to be expected for any future interim or annual period. Recently Issued Accounting Pronouncements In June 2016, the Financial Accounting Standards Board ("FASB") issued Accounting Standards Update ("ASU") 2016-13, "Measurement of Credit Losses on Financial Instruments," which amends the FASB's guidance on the impairment of financial instruments. The ASU adds to U.S. GAAP an impairment model ("current expected credit loss model"). Under this new guidance, an entity recognizes as an allowance its estimate of expected credit losses. The ASU is effective for fiscal years beginning after December 15, 2019. The Company has performed a preliminary analysis and determined which areas are in and out of scope and which areas that it can apply the practical expedient. The Company is currently assessing the impact of applying the CECL model to areas such as defaulted note receivables and investment banking related receivables accounts. The Company has also determined that it will utilize the practical expedient to areas such as securities borrowed, reverse repurchase agreements, margin lending, and other collateralized transactions due to the continued marking of the underlying collateral. As a result, the Company does not expect the adoption of this ASU to have a material impact on its condensed consolidated financial statements. In January 2017, the FASB issued ASU 2017-04, "Intangibles - Goodwill and Other, Simplifying the Test for Goodwill Impairment," which simplifies the subsequent measurement of goodwill. The Company is no longer required to perform its Step 2 goodwill impairment test; instead, the Company should perform its annual or interim goodwill impairment test by comparing the fair value of a reporting unit with its carrying amount. The ASU is effective for fiscal years beginning after December 15, 2019 and early adoption is permitted. The Company will not early adopt this ASU. The Company is currently evaluating the impact, if any, of the ASU on the Company; the adoption of the ASU is not currently expected to have a material impact on its condensed consolidated financial statements. In August 2018, the FASB issued ASU 2018-13, "Fair Value Measurement - Disclosure Framework - Changes to the Disclosure Requirements for the Fair Value Measurement," which modifies the disclosure requirements related to fair value measurement. The ASU is effective for fiscal years and interim periods beginning after December 15, 2019 and early adoption is permitted. The Company will not early adopt this ASU. The Company is currently evaluating the impact, if any, of the ASU on the Company's disclosure.

Basis of Presentation

The accompanying condensed consolidated financial statements of the Company have been prepared pursuant to the rules and regulations of the U.S. Securities and Exchange Commission (the "SEC") regarding interim financial reporting. Accordingly, they do not include all of the information and notes required by accounting principles generally accepted in the United States of America ("U.S. GAAP") for complete financial statements and should be read in conjunction with the audited consolidated financial statements and notes thereto included in the Company's Annual Report on Form 10-K for the year ended December 31, 2018 (the "Form 10-K"). The accompanying condensed consolidated balance sheet data was derived from the audited consolidated financial statements, but does not include all disclosures required by U.S. GAAP for annual financial statement purposes. The accompanying condensed consolidated financial statements reflect all adjustments which are, in the opinion of management, necessary for a fair presentation of the financial position, results of operations and cash flows for the interim periods presented. Preparing financial statements requires management to make estimates and assumptions that affect the amounts that are reported in the financial statements and the accompanying disclosures. Although these estimates are based on management's knowledge of current events and actions that the Company may undertake in the future, actual results may differ materially from the estimates. The condensed consolidated results of operations for the nine month period ended September 30, 2019 are not necessarily indicative of the results to be expected for any future interim or annual period.

Recently Issued Accounting Pronouncements

In June 2016, the Financial Accounting Standards Board ("FASB") issued Accounting Standards Update ("ASU") 2016-13, "Measurement of Credit Losses on Financial Instruments," which amends the FASB's guidance on the impairment of financial instruments. The ASU adds to U.S. GAAP an impairment model ("current expected credit loss model"). Under this new guidance, an entity recognizes as an allowance its estimate of expected credit losses. The ASU is effective for fiscal years beginning after December 15, 2019. The Company has performed a preliminary analysis and determined which areas are in and out of scope and which areas that it can apply the practical expedient. The Company is currently assessing the impact of applying the CECL model to areas such as defaulted note receivables and investment banking related receivables accounts. The Company has also determined that it will utilize the practical expedient to areas such as securities borrowed, reverse repurchase agreements, margin lending, and other collateralized transactions due to the continued marking of the underlying collateral. As a result, the Company does not expect the adoption of this ASU to have a material impact on its condensed consolidated financial statements.

In January 2017, the FASB issued ASU 2017-04, "Intangibles - Goodwill and Other, Simplifying the Test for Goodwill Impairment," which simplifies the subsequent measurement of goodwill. The Company is no longer required to perform its Step 2 goodwill impairment test; instead, the Company should perform its annual or interim goodwill impairment test by comparing the fair value of a reporting unit with its carrying amount. The ASU is effective for fiscal years beginning after December 15, 2019 and early adoption is permitted. The Company will not early adopt this ASU. The Company is currently evaluating the impact, if any, of the ASU on the Company; the adoption of the ASU is not currently expected to have a material impact on its condensed consolidated financial statements.

In August 2018, the FASB issued ASU 2018-13, "Fair Value Measurement - Disclosure Framework - Changes to the Disclosure Requirements for the Fair Value Measurement," which modifies the disclosure requirements related to fair value measurement. The ASU is effective for fiscal years and interim periods beginning after December 15, 2019 and early adoption is permitted. The Company will not early adopt this ASU. The Company is currently evaluating the impact, if any, of the ASU on the Company's disclosure.