Fair Value Measurements (Details) - USD ($) $ in Thousands	Sep. 30, 2016	Dec. 31, 2015
Assets
Securities owned, at fair value:	$ 8,678	$ 5,598
Liabilities
Securities sold, not yet purchased, at fair value:	6,143	2,637
Recurring basis
Assets
Total Assets	8,679	5,631
Liabilities
Total Liabilities	6,143	2,637
Recurring basis \| Tax free money market mutual funds
Assets
Cash and cash equivalents:		33
Recurring basis \| Money market mutual funds
Assets
Cash and cash equivalents:	1
Recurring basis \| Corporate stocks-trading securities
Assets
Securities owned, at fair value:	6,171	2,571
Liabilities
Securities sold, not yet purchased, at fair value:	6,143	2,637
Recurring basis \| Mutual funds
Assets
Securities owned, at fair value:	2,507	3,027
Recurring basis \| Level 1
Assets
Total Assets	8,679	5,631
Liabilities
Total Liabilities	6,143	2,637
Recurring basis \| Level 1 \| Tax free money market mutual funds
Assets
Cash and cash equivalents:		33
Recurring basis \| Level 1 \| Money market mutual funds
Assets
Cash and cash equivalents:	1
Recurring basis \| Level 1 \| Corporate stocks-trading securities
Assets
Securities owned, at fair value:	6,171	2,571
Liabilities
Securities sold, not yet purchased, at fair value:	6,143	2,637
Recurring basis \| Level 1 \| Mutual funds
Assets
Securities owned, at fair value:	$ 2,507	$ 3,027

Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=36462937&loc=d3e19207-110258

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Fair value portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Cash
-URI http://asc.fasb.org/extlink&oid=6506951

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Cash Equivalents
-URI http://asc.fasb.org/extlink&oid=6507016

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The aggregate fair value as of the balance sheet date of financial instruments and other positions owned by the entity 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. Includes both pledged and unpledged holdings.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 940
-SubTopic 320
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=35711157&loc=d3e42546-110969

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Fair value of obligations incurred from short sales.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 940
-SubTopic 320
-Section 35
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=35711043&loc=d3e42429-110968

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Fair value of financial and nonfinancial obligations.

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