Collateralized Transactions - Additional Information (Detail) - USD ($)	3 Months Ended
Mar. 31, 2020	Dec. 31, 2019	Mar. 31, 2019
Securities Financing Transaction [Line Items]
Repurchase agreements	$ 512,000
Securities loaned	2,973,000	$ 13,902,000
CF & Co [Member]
Securities Financing Transaction [Line Items]
Repurchase agreements	$ 500,000		$ 0
Repurchase agreements maturity date	Apr. 01, 2020
Securities loaned	$ 3,000,000.0	$ 13,900,000
Stated interest rate	0.58%	2.45%
CF & Co [Member] \| Securities Financing Transaction, Fair Value [Member]
Securities Financing Transaction [Line Items]
Securities loaned	$ 2,800,000	$ 13,900,000
CF & Co [Member] \| Securities Financing Transaction, Fair Value [Member] \| Fair Value [Member]
Securities Financing Transaction [Line Items]
Securities loaned	$ 2,800,000	$ 13,900,000

Repurchase agreements maturity date.

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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

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+ References

No definition available.

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- Definition

Amount, after the effects of master netting arrangements, of securities loaned to entities in exchange for collateral. Includes liabilities not subject to a master netting arrangement and not elected to be offset.

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- Definition

Amount, after the effects of master netting arrangements, of funds outstanding borrowed in the form of a security repurchase agreement between the entity and another party for the sale and repurchase of identical or substantially the same securities at a date certain for a specified price. Includes liabilities not subject to a master netting arrangement and not elected to be offset.

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