Receivables From And Payables To Brokers, Dealers And Clearing Organizations (Amounts Receivable From Brokers, Dealers, And Clearing Organizations) (Details) - USD ($) $ in Thousands	Jun. 30, 2018	Dec. 31, 2017
Due To And From Broker Dealers And Clearing Organizations [Abstract]
Receivables from clearing organizations	$ 465,589	$ 270,285
Deposits paid for securities borrowed	143,919	132,776
Securities failed to deliver	62,652	56,046
Receivables from brokers, dealers and clearing organizations, Total	$ 672,160	$ 459,107

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

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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 210
-Section S99
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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
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 45
-Paragraph 2
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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://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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-SubTopic 20
-Section 25
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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.

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