Broker-Dealer and Clearing Organization Receivables and Payables (Details) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Receivables:
Securities borrowed	$ 1,990,598	$ 152,899
Securities failed to deliver	23,693us-gaap_SecuritiesFailedToDeliver	3,497us-gaap_SecuritiesFailedToDeliver
Clearing organizations	8,364	11,471
Trades in process of settlements, net	190,280
Other	9,582us-gaap_OtherReceivables	17us-gaap_OtherReceivables
Total receivables	2,222,517	167,884
Payables:
Securities loaned	1,853,366	117,822
Correspondents	59,282us-gaap_DueToCorrespondentBrokers	51,930us-gaap_DueToCorrespondentBrokers
Securities failed to receive	27,351us-gaap_SecuritiesFailedToReceive	5,960us-gaap_SecuritiesFailedToReceive
Clearing organizations	11,041	3,330
Total Payables	$ 1,951,040	$ 179,042

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

No definition available.

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- Definition

Amount payable to broker-dealers or clearing organizations for executing or clearing trades or orders.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 940

-SubTopic 20

-Section 25

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=35710027&loc=d3e41256-110953

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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 SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 6

-Article 9

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

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- Definition

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

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-Name Regulation S-X (SX)

-Number 210

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-Topic 942

-SubTopic 210

-Section S99

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-Subparagraph (SX 210.9-03.12)

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Amount payable to correspondent broker-dealer.

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No definition available.

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- Definition

Carrying amounts due as of the balance sheet date from parties or arising from transactions not otherwise specified in the taxonomy.

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

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-Paragraph 1

-Subparagraph (SX 210.5-02.8)

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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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- 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/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

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-Paragraph 2

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Fail-to-Deliver

-URI http://asc.fasb.org/extlink&oid=34716026

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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.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

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