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Dividend Income, Amount Per Share, Net Of Tax

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The number of shares converted in a noncash (or part noncash) transaction. Noncash is defined as transactions during a period that do not result in cash receipts or cash payments in the period. "Part noncash" refers to that portion of the transaction not resulting in cash receipts or cash payments in the period.

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Amount, before tax, of realized gain (loss) from foreign currency transaction.

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Number of shares of investment owned.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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The carrying value of securities purchased to be resold in reverse repurchase transactions as of the balance sheet date.

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Related Party Transactions - Other Agreements with Cantor (Details) - USD ($)		3 Months Ended
	Jul. 01, 2023	Mar. 31, 2026	Mar. 31, 2025	Dec. 31, 2025	Oct. 06, 2025	May 16, 2025
Related Party Transaction [Line Items]
Repurchase agreements		$ 0		$ 0
Reverse repurchase agreements		0		0
Commissions		$ 752,935,000	$ 494,711,000
Conversion of stock, shares converted (in shares)	64,000,000.0
Minimum number of shares required to be issued (in shares)	75,000,000
Mr. Howard W. Lutnick
Related Party Transaction [Line Items]
Shares issued, price per share, after tax (in dollars per share)					$ 0.032	$ 9.2082
Class A Common Stock \| Cantor
Related Party Transaction [Line Items]
Investment owned, balance (in shares)		0
Class A Common Stock \| CFGM
Related Party Transaction [Line Items]
Investment owned, balance (in shares)		0
Class B Common Stock \| Cantor \| Mr. Howard W. Lutnick
Related Party Transaction [Line Items]
Shares issued, price per share, after tax (in dollars per share)					$ 0.032
Class B Common Stock \| Cantor
Related Party Transaction [Line Items]
Investment owned, balance (in shares)		102,300,000
Class B Common Stock \| Cantor \| Mr. Howard W. Lutnick
Related Party Transaction [Line Items]
Investment owned, balance (in shares)					8,973,721
Class B Common Stock \| CFGM
Related Party Transaction [Line Items]
Investment owned, balance (in shares)		3,000,000.0
Related Party
Related Party Transaction [Line Items]
Repurchase agreements		$ 0		0
Reverse repurchase agreements		0		$ 0
Recognition of share of FX gains (losses)		(2,800,000)	7,500,000
Commissions		$ 100,000	$ 100,000
Related Party \| Class B Common Stock \| Cantor
Related Party Transaction [Line Items]
Conversion of stock, shares converted (in shares)	64,000,000.0