Broker-Dealer and Clearing Organization Receivables and Payables (Details) - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016
Receivables:
Securities borrowed	$ 1,611,885	$ 1,436,069
Securities failed to deliver	25,478	33,834
Trades in process of settlements	16,545	10,223
Other	18,215	17,615
Total receivables	1,672,123	1,497,741
Payables:
Securities loaned	1,447,570	1,283,676
Correspondents	27,225	31,040
Securities failed to receive	39,312	31,724
Other	3,591	688
Total Payables	$ 1,517,698	$ 1,347,128

Amount of other receivables due from trades in process of settlement.

No definition available.

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(6))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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-Publisher FASB
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-Section 50
-Paragraph 3
-Subparagraph (b)
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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 946
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.6-04(11))
-URI http://asc.fasb.org/extlink&oid=6488278&loc=d3e603758-122996

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- Definition

Amount payable to correspondent broker-dealer.

+ References

No definition available.

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- Definition

Amount of other payables due to broker-dealers or clearing organizations.

+ References

No definition available.

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- Definition

Amount due from parties in nontrade transactions, classified as other.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.8)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

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.

+ References

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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://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 940
-SubTopic 20
-Section 45
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=35710130&loc=d3e41645-110958

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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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-URI http://asc.fasb.org/extlink&oid=34716026

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- Definition

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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Fail-to-Receive
-URI http://asc.fasb.org/extlink&oid=34716056

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