Deposits with Clearing Organizations, Brokers and Banks (Details) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Deposits with Clearing Organizations, Brokers and Banks [Abstract]
Deposits with clearing organizations, brokers and banks	$ 101,399	$ 93,996

The amount of securities on deposit with clearing organizations and other entities which provide services necessary to operations of the Company. This item would include, for instance, securities advanced as refundable collateral for securities borrowed.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.8,17)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Name:	us-gaap_DepositsWithClearingOrganizationsAndOthersSecurities
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant