Receivables and Payables - Brokers, Dealers, and Clearing Organizations (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Receivables from brokers, dealers and clearing organizations
Broker-dealers	$ 247,214	$ 189,817
Clearing organizations	940	708
Securities borrowed	27,713	4,246
Allowance for doubtful accounts	(1,121)	(864)
Total	274,746	193,907
Payables to brokers, dealers and clearing organizations
Broker-dealers	200,579	105,022
Clearing organizations	33,367	10,011
Securities loaned	94,248	4,245
Total	$ 328,194	$ 119,278

Amounts payable to clearing organizations on open transactions and floor-brokerage payables.

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- Definition

Represents the allowance for doubtful accounts on receivables from brokers, dealers and clearing organizations.

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- Definition

This is the amount of cash advanced as security in return for borrowing securities from another party.

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- Definition

The amount of cash received as security in return for loaning securities to another party.

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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 payable to broker-dealers and clearing organizations, including, but not limited to, securities failed-to-receive, certain deposits received for securities loaned, open transactions, and floor-brokerage payables.

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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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