Related Party Disclosures	9 Months Ended
Sep. 30, 2019
Related Party Transactions [Abstract]
Related Party Disclosures	11. Related Party Disclosures StockCross StockCross and the Company are under common ownership and StockCross serves as one of the two clearing brokers for the Company. StockCross has a clearing agreement with MSCO in which StockCross passes through all revenue and charges MSCO for related clearing expenses. Outside of the clearing agreement, MSCO has an expense sharing agreement with StockCross for its Beverly Hills and Jersey City offices and StockCross pays some vendors for miscellaneous expenses which it passes through to MSCO. As of September 30, 2019 and December 31, 2018, MSCO had receivables from StockCross totaling approximately $1.7 million and $1.3 million, respectively, consisting of financing for inventory positions, the net monthly clearing fees StockCross owes MSCO, and a clearing deposit. As of September 30, 2019 and December 31, 2018, MSCO had a payable to StockCross totaling $27,000 and $46,000, respectively. In January 2019, the Company purchased approximately 15% of StockCross’ outstanding shares and in July 2019 the Company entered into a binding letter of intent to purchase the remaining 85% of StockCross. For the three months and nine months ended September 30, 2019, the earnings recognized from the Company’s 15% investment in StockCross was $30,000 and $84,000, respectively. Please see Item 4. Financial Statements and Supplementary Data – “Note 6 – Equity Method Investments” for additional detail on the transaction with StockCross. Kennedy Cabot Acquisition (“KCA”) KCA is an affiliate of the Company and StockCross. To gain efficiencies and economies of scale with billing and administrative functions, KCA serves as a paymaster for the Company and StockCross for compensation and benefits expenses, the entirety of which KCA passes through to the Company and StockCross proportionally. In addition, KCA has purchased the naming rights for the Company for the Company to use. PWC PWC brokers the insurance policies for related parties. Revenue for PWC from related parties was $3,000 and $67,000 for the three months and nine months ended September 30, 2019, respectively. Revenue for PWC from related parties was $16,000 and $61,000 for the three and nine months ended September 30, 2018.

11. Related Party Disclosures

StockCross

StockCross and the Company are under common ownership and StockCross serves as one of the two clearing brokers for the Company. StockCross has a clearing agreement with MSCO in which StockCross passes through all revenue and charges MSCO for related clearing expenses. Outside of the clearing agreement, MSCO has an expense sharing agreement with StockCross for its Beverly Hills and Jersey City offices and StockCross pays some vendors for miscellaneous expenses which it passes through to MSCO. As of September 30, 2019 and December 31, 2018, MSCO had receivables from StockCross totaling approximately $1.7 million and $1.3 million, respectively, consisting of financing for inventory positions, the net monthly clearing fees StockCross owes MSCO, and a clearing deposit. As of September 30, 2019 and December 31, 2018, MSCO had a payable to StockCross totaling $27,000 and $46,000, respectively. In January 2019, the Company purchased approximately 15% of StockCross’ outstanding shares and in July 2019 the Company entered into a binding letter of intent to purchase the remaining 85% of StockCross. For the three months and nine months ended September 30, 2019, the earnings recognized from the Company’s 15% investment in StockCross was $30,000 and $84,000, respectively. Please see Item 4. Financial Statements and Supplementary Data – “Note 6 – Equity Method Investments” for additional detail on the transaction with StockCross.

Kennedy Cabot Acquisition (“KCA”)

KCA is an affiliate of the Company and StockCross. To gain efficiencies and economies of scale with billing and administrative functions, KCA serves as a paymaster for the Company and StockCross for compensation and benefits expenses, the entirety of which KCA passes through to the Company and StockCross proportionally. In addition, KCA has purchased the naming rights for the Company for the Company to use.

PWC

PWC brokers the insurance policies for related parties. Revenue for PWC from related parties was $3,000 and $67,000 for the three months and nine months ended September 30, 2019, respectively. Revenue for PWC from related parties was $16,000 and $61,000 for the three and nine months ended September 30, 2018.