Cash and Securities Segregated Under Federal Regulations and Other Requirements	12 Months Ended
Dec. 31, 2020
Brokers and Dealers [Abstract]
Cash and Securities Segregated Under Federal Regulations and Other Requirements	Cash and Securities Segregated Under Federal Regulations and Other RequirementsAs of December 31, 2020 and 2019, $1.8 billion and $1.1 billion, respectively, of U.S. Treasury Bills were segregated in a special reserve bank custody account for the exclusive benefit of our brokerage customers under Rule 15c3-3 of the Exchange Act.

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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