Collateralized Transactions - Disaggregation of Gross Obligation by Class (Details) $ in Thousands	Dec. 31, 2015 USD ($)
Financial Instruments Owned and Pledged as Collateral [Line Items]
Gross amount of recognized liabilities for repurchase agreements and securities loaned	$ 857,646
Maturity Overnight and Open
Financial Instruments Owned and Pledged as Collateral [Line Items]
Gross amount of recognized liabilities for repurchase agreements and securities loaned	857,646
Maturity Less than 30 Days
Financial Instruments Owned and Pledged as Collateral [Line Items]
Gross amount of recognized liabilities for repurchase agreements and securities loaned	0
U.S. Government, agency and sovereign obligations
Financial Instruments Owned and Pledged as Collateral [Line Items]
U.S. Treasury and Agency securities	726,988
U.S. Government, agency and sovereign obligations \| Maturity Overnight and Open
Financial Instruments Owned and Pledged as Collateral [Line Items]
U.S. Treasury and Agency securities	726,988
U.S. Government, agency and sovereign obligations \| Maturity Less than 30 Days
Financial Instruments Owned and Pledged as Collateral [Line Items]
U.S. Treasury and Agency securities	0
Equity securities
Financial Instruments Owned and Pledged as Collateral [Line Items]
Equity securities	130,658
Equity securities \| Maturity Overnight and Open
Financial Instruments Owned and Pledged as Collateral [Line Items]
Equity securities	130,658
Equity securities \| Maturity Less than 30 Days
Financial Instruments Owned and Pledged as Collateral [Line Items]
Equity securities	$ 0

Amount, before effects of master netting arrangements, of funds outstanding borrowed in the form of a financial asset repurchase agreement between the entity and another party for the sale and repurchase of identical or substantially the same financial asset at a date certain for a specified price. Includes repurchase-to-maturity transactions and liabilities not subject to a master netting arrangement.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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- Definition

Amount, before effects of master netting arrangements, of securities loaned to entities in exchange for collateral and funds outstanding borrowed in the form of a security repurchase agreement between the entity and another party for the sale and repurchase of identical or substantially the same securities at a date certain for a specified price. Includes liabilities not subject to a master netting arrangement.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 30
-Section 50
-Paragraph 7
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=55761124&loc=SL34722452-111729

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 50
-Paragraph 3
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=51824906&loc=SL20225862-175312

+ Details

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- Definition

Amount, before effects of master netting arrangements, of financial assets loaned to entities in exchange for collateral. Includes liabilities not subject to a master netting arrangement and financial assets transferred other than securities that qualify as secured borrowings.

+ References

+ Details

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