Receivables From and Payables to Brokers, Dealers, and Clearing Organizations (Amounts Receivable from Brokers, Dealers, and Clearing Organizations) (Details) - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023
Due to and from Broker-Dealers and Clearing Organizations [Abstract]
Receivable from clearing organizations	$ 408,614	$ 178,991
Deposits paid for securities borrowed	204,150	215,368
Securities failed to deliver	45,107	19,785
Receivables from brokers, dealers and clearing organizations, Total	$ 657,871	$ 414,144

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

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 942
-SubTopic 470
-Section 50
-Paragraph 3
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480848/942-470-50-3

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- References

No definition available.

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- Definition

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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Section 45
-Paragraph 3
-SubTopic 20
-Topic 940
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481833/940-20-45-3

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- Definition

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.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 940
-SubTopic 310
-Name Accounting Standards Codification
-Publisher FASB
-URI https://asc.fasb.org//940-310/tableOfContent

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- Definition

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.

+ References

No definition available.

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