Segregated Cash	9 Months Ended
Sep. 30, 2021
Segregated Cash [Abstract]
Segregated Cash	Segregated CashAs of September 30, 2021 and December 31, 2020, cash segregated in compliance with federal regulations and other restricted deposits of $177.7 million and $185.1 million, respectively, consisted of cash deposited in Special Reserve Bank Accounts for the exclusive benefit of customers under SEC Rule 15c3-3 and cash deposited in Special Reserve Bank Accounts for the exclusive benefit of Proprietary Accounts of Broker-Dealers ("PAB") under SEC Rule 15c3-3

The entire disclosure for assets that are restricted in their use, generally by contractual agreements or regulatory requirements. This would include, but not limited to, a description of the restricted assets and the terms of the restriction.

No definition available.

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