Receivables From and Payables to Brokers, Dealers and Clearing Organizations (Amounts Receivable from Brokers, Dealers, and Clearing Organizations) (Details) (USD $) In Thousands	Jun. 30, 2011	Dec. 31, 2010
Receivables From and Payables to Brokers, Dealers and Clearing Organizations
Deposits paid for securities borrowed	$ 219,465	$ 94,709
Securities failed to deliver	82,121	74,991
Receivable from clearing organizations	9,214	78,007
Receivables from brokers, dealers and clearing organizations, Total	$ 310,800	$ 247,707

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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 03
-Paragraph 6
-Article 9

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- Definition

Amount receivable from securities failed to deliver, certain deposits for securities borrowed, open transactions, good faith and margin deposits, commissions and floor brokerage items. Also cash and securities [guarantee] on deposit with [commodities] clearing organizations and other entities which provide services necessary to operations of the Company. This item would include, for instance, cash and securities advanced as [refundable] collateral for securities borrowed.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher AICPA
-Name Audit and Accounting Guide (AAG)
-Number AAG-BRD
-Chapter 4
-Paragraph 80
-Subparagraph Exhibit 4-8, 4
-IssueDate 2006-05-01
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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- Definition

Cash and securities on deposit with the expectation that such deposits will be returned with organizations that provide efficient and orderly trade clearance and settlement services for which broker-dealers pay fees. 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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- Definition

Amount recorded when a Broker Dealer sells securities but does not deliver the securities on settlement date. The amount recorded is the selling price including any accrued interest. This asset is collected upon delivery of the securities.

+ References

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