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Related Party Transactions - Other Agreements with Cantor (Details) shares in Millions						12 Months Ended
	Nov. 30, 2018 shares	Nov. 24, 2018 shares	Nov. 23, 2018 USD ($) shares	Aug. 06, 2018 USD ($)	Jun. 05, 2015 shares	Dec. 31, 2022 USD ($) shares	Dec. 31, 2021 USD ($)	Dec. 31, 2020 USD ($)	Aug. 05, 2018 USD ($)	Mar. 19, 2018 USD ($)	Aug. 31, 2013 USD ($)
Related Party Transaction [Line Items]
Commissions						$ 1,281,294,000	$ 1,541,900,000	$ 1,567,668,000
Limited partnership interest, conversion ratio						1
Common stock, issued during the period, additional consideration			$ 0
Interest expense from affiliate						$ 0	0	400,000
Cantor
Related Party Transaction [Line Items]
Recognition of share of FX gains (losses)						100,000	500,000	1,500,000
Commissions						300,000	100,000	$ 100,000
Investment authorization in asset-backed commercial paper program											$ 350,000,000
Securities for reverse repurchase agreements						0	0
Cantor \| Revolving Credit Facility
Related Party Transaction [Line Items]
Principal amount of notes				$ 400,000,000					$ 250,000,000	$ 250,000,000
Debt instrument, extended term				1 year
Debt instrument, non-extension notice term				6 months
Debt instrument, basis point				1.00%
Line of credit facility, borrowing amount						$ 0	$ 0
CF Group Management, Inc.
Related Party Transaction [Line Items]
Exchange class A to class B common stock (in shares) \| shares	23.6		0.7		34.6
Cantor Rights to Purchase Exchangeable Units
Related Party Transaction [Line Items]
Exchange class A to class B common stock (in shares) \| shares			10.3
Cantor Rights to Purchase Exchangeable Units \| Maximum
Related Party Transaction [Line Items]
Exchange class A to class B common stock (in shares) \| shares					34.6
Cantor Rights to Purchase Exchangeable Units \| Maximum \| Class B Common Stock
Related Party Transaction [Line Items]
Exchange class A to class B common stock (in shares) \| shares						23.6
Cantor and CFGM \| Class B Common Stock
Related Party Transaction [Line Items]
Exchange class A to class B common stock (in shares) \| shares		23.6