Segregated Cash	12 Months Ended
Dec. 31, 2020
Segregated Cash [Abstract]
Segregated Cash	Segregated CashAs of December 31, 2020 and 2019, cash segregated in compliance with federal regulations and other restricted deposits of $185.1 million and $107.3 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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