Receivables from/Payables to Broker-Dealers and Clearing Organizations (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Assets
Due from prime brokers	$ 643,089	$ 418,059
Deposits with clearing organizations	386,460	231,977
Net equity with futures commission merchants	207,213	267,748
Unsettled trades with clearing organizations	392,349	214,618
Securities failed to deliver	228,677	178,324
Commissions and fees	24,093	7,858
Total receivables from broker-dealers and clearing organizations	1,881,881	1,318,584
Liabilities
Due to prime brokers	330,078	511,524
Net equity with futures commission merchants	69,480	50,950
Unsettled trades with clearing organizations	178,361	118,286
Securities failed to receive	93,973	144,494
Commissions and fees	3,140	1,496
Total payables to broker-dealers and clearing organizations	675,032	826,750
Outstanding principal balance	$ 163,600	$ 134,300

Amount payable to other broker-dealer and clearing organization, including, but not limited to, security failed-to-receive, deposit received for security loaned, open transaction, and floor-brokerage payable.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher SEC
-Name Rule 15c3-1
-Number 240
-Section 15c3-1

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Amount receivable from broker-dealers from commissions for executing orders on the floor of an exchange.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 940
-SubTopic 20
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Amount payable to broker-dealers or clearing organizations for executing or clearing trades or orders.

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Amount receivable from correspondent broker-dealer.

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Amount payable to correspondent broker-dealer.

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Amount receivable from broker-dealers and clearing organizations, including, but not limited to, securities failed-to-deliver, certain deposits for securities borrowed, open transactions, good faith and margin deposits, commissions and floor brokerage receivables.

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Amount of right to receive cash and securities on deposit with clearing organizations. Clearing organizations perform post trade processing and trade comparisons among numerous broker-dealers and act as settlement agents between buying and selling broker-dealers.

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Amount receivable as the result of a fail-to-deliver. A fail-to-deliver is a securities sale to another broker-dealer that has not been delivered to buying broker-dealer by the close of business on the settlement date.

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Amount payable as the result of fail-to-receive. A fail-to-receive is a securities purchase from another broker-dealer not received from the selling broker-dealer by the close of business on the settlement date.

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Represents the amount of net equity with futures commission merchants, asset.

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Represents the amount of net equity with futures commission merchants, liability.

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Represents the amount receivable for unsettled trades.

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