Collateralized Transactions (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Securities received as collateral:
Securities borrowed	$ 1,526,350	$ 1,361,635
Securities purchased under agreements to resell	18,796	15,475
Securities received as collateral	1,545,146	1,377,110
Financial instruments owned and pledged	920,950	791,115
Equities
Securities received as collateral:
Financial instruments owned and pledged	878,727	748,846
Exchange traded notes
Securities received as collateral:
Financial instruments owned and pledged	$ 42,223	$ 42,269

The total of collateralized agreements including securities purchased under agreements to resell (repos), borrowed securities, and secured demand notes.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(m)(2)(i)(A))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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-Topic 860
-SubTopic 10
-Section 05
-Paragraph 16
-URI http://asc.fasb.org/extlink&oid=109246787&loc=d3e93640-111703

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The fair value of federal funds sold and securities purchased under agreements to resell that serve as collateral for borrowings.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 30
-Section 50
-Paragraph 1A
-Subparagraph (c)(1)
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- Definition

The fair value as of the balance sheet date of financial instruments and other positions owned by the entity and pledged to counterparties as collateral, including: (1) mortgages, mortgage-backed and asset backed securities; (2) US government and agency obligations; (3) state and municipal government obligations; (4) other sovereign government debt; (5) corporate obligations; (6) corporate equities; (7) principal investments; (8) derivative contracts; and (9) physical commodities.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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-Topic 860
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-Section 45
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Amount, after the effects of master netting arrangements, of securities borrowed from entities in exchange for collateral. Includes assets not subject to a master netting arrangement and not elected to be offset, at market value.

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