Collateralized Transactions - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2019	Dec. 31, 2018
Securities Financing Transaction [Line Items]
Repurchase agreements	$ 4,327	$ 986
Securities loaned	25,068	15,140
CF & Co [Member]
Securities Financing Transaction [Line Items]
Repurchase agreements	$ 4,300	1,000
Repurchase agreements maturity date	Apr. 01, 2019
Securities loaned	$ 25,100	$ 15,100
Stated interest rate		2.90%
CF & Co [Member] \| Securities Financing Transaction, Fair Value [Member]
Securities Financing Transaction [Line Items]
Securities loaned	25,300	$ 15,300
CF & Co [Member] \| Securities Financing Transaction, Fair Value [Member] \| Fair Value [Member]
Securities Financing Transaction [Line Items]
Securities loaned	$ 25,300	$ 15,300
CF & Co [Member] \| Minimum [Member]
Securities Financing Transaction [Line Items]
Stated interest rate	2.95%
CF & Co [Member] \| Maximum [Member]
Securities Financing Transaction [Line Items]
Stated interest rate	3.25%

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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