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Compensation - Units Redeemed in Connection with Issuance of Class A Common Stock (Details) - shares | 3 Months Ended
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Mar. 31, 2021 | Mar. 31, 2020
Share-based Compensation Arrangement by Share-based Payment Award |  |
Number of units redeemed (in shares) | 686,544 | 291,721
BGC Units |  |
Share-based Compensation Arrangement by Share-based Payment Award |  |
Number of units redeemed (in shares) | 46,605 | 149,280
Newmark Units |  |
Share-based Compensation Arrangement by Share-based Payment Award |  |
Number of units redeemed (in shares) | 639,939 | 142,441

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- Definition Share based compensation arrangement by share based payment award units redeemed. + References No definition available. + Details
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- Definition 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. + References No definition available. + Details
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- Details
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- Details
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