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Related Party Transactions - Additional Information (Detail) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 1 Months Ended | 3 Months Ended | 12 Months Ended |  |  |  |  |  |  |
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Sep. 27, 2019 USD ($) | Mar. 27, 2019 $ / shares shares | Mar. 05, 2019 $ / shares shares | Feb. 22, 2019 USD ($) $ / shares shares | Feb. 01, 2019 USD ($) $ / shares shares | Nov. 30, 2018 shares | Nov. 23, 2018 USD ($) shares | Oct. 03, 2018 $ / shares shares | Jul. 24, 2018 USD ($) | Mar. 19, 2018 USD ($) | Mar. 07, 2018 USD ($) $ / shares shares | Feb. 26, 2018 $ / shares shares | Dec. 13, 2017 | Nov. 04, 2016 USD ($) | Oct. 25, 2016 shares | May 27, 2016 USD ($) | Jun. 05, 2015 shares | Nov. 30, 2014 | Mar. 31, 2019 shares | Dec. 31, 2019 USD ($) $ / shares shares | Dec. 31, 2018 USD ($) $ / shares shares | Dec. 31, 2017 USD ($) shares | Dec. 31, 2015 USD ($) | Aug. 08, 2019 USD ($) | Feb. 27, 2019 USD ($) | Aug. 06, 2018 USD ($) | Feb. 16, 2018 USD ($) | Sep. 08, 2017 USD ($) | Apr. 21, 2017 USD ($) | Aug. 31, 2013 USD ($)
Related Party Transactions [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Cantor's share of net profit in Tower Bridge |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 29,236,000 | $ 29,993,000 | $ 36,167,000 |  |  |  |  |  |  |  |
Payment percentage of the gross proceeds from the sale of shares |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 2.00% |  |  |  |  |  |  |  |  |  |  |  |
Number of shares, right to exchange from Class A to Class B common stock | shares |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 11,036,273 |  |  |  |  |  |  |  |  |
Equity method investments |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 40,000,000 | $ 35,211,000 |  |  |  |  |  |  |  |  |
Equity investment |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 1,715,000 | 925,000 | 106,824,000 |  |  |  |  |  |  |  |
Repurchase agreements |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 986,000 |  |  |  |  |  |  |  |  |
Commissions |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 1,645,818,000 | 1,511,522,000 | 1,334,383,000 |  |  |  |  |  |  |  |
Common stock, issued during the period, additional consideration |  |  |  |  |  |  | $ 0 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Principal sum of loan due from related parties |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 14,273,000 | 7,748,000 |  |  |  |  |  |  |  |  |
Line of credit facility, outstanding amount |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 0 |  |  |  |  |  |  |  |  |  |
Interest expense |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 59,077,000 | 41,733,000 | 76,958,000 |  |  |  |  |  |  |  |
Payables to Cantor related to open derivative contracts |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 72,497,000 | 40,155,000 |  |  |  |  |  |  |  |  |
Employee loans |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 315,590,000 | 216,868,000 |  |  |  |  |  |  |  |  |
Interest income |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 18,319,000 | 14,404,000 | 14,557,000 |  |  |  |  |  |  |  |
Aggregate proceeds from issuance of common stock |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 327,624,000 | $ 26,606,000 |  |  |  |  |  |  |  |
Securities loaned |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 13,902,000 | $ 15,140,000 |  |  |  |  |  |  |  |  |
Limited Partnership Units Exchange Ratio |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 1 |  |  |  |  |  |  |  |  |  |
Repurchase of Class A common stock, shares | shares |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 233,000 | 233,000 |  |  |  |  |  |  |  |  |  |
Mr. Lutnick [Member] | Preferred Units [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Related Party Transactions [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Determination price | $ / shares |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 6.57 |  |  |  |  |  |  |  |  |
Number of non-exchangeable units redeemed | shares |  |  |  |  | 376,651 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 760,797 |  |  |  |  |  |  |  |  |
Non-exchangeable units redemption, value |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 5,000,000 |  |  |  |  |  |  |  |  |
Number of non-exchangeable PSU approved redemption | shares |  |  |  |  | 376,651 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Exchange share price | $ / shares |  |  |  |  | $ 6.21 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of LPU issued on exchangeable |  |  |  |  | $ 2,339,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of PLPU share issued for non exchangeable | shares |  |  |  |  | 463,969 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Payment of witholding tax rate for common stock issue |  |  |  |  | $ 2,661,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Mr. Merkel [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Related Party Transactions [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share Price | $ / shares |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 5.17 |  |  |  |  |  |  |  |  |
Number of non-exchangeable PSU approved cancellation | shares |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 113,032 |  |  |  |  |  |  |  |  |
Number of non-exchangeable PPSU approved cancellation | shares |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 89,225 |  |  |  |  |  |  |  |  |
Determination price | $ / shares |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 5.36 |  |  |  |  |  |  |  |  |
Number of shares issued for non-exchangeable units | shares |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 1,062,500 |  |  |  |  |  |  |  |  |
Number of shares issued for non-exchangeable units, net | shares |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 113,032 |  |  |  |  |  |  |  |  |
Percentage of withholding tax rate for common shares issued |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 45.00% |  |  |  |  |  |  |  |  |
Payment related to withholding tax rate for common shares issued |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 478,123 |  |  |  |  |  |  |  |  |
Mr. Windeatt [Member] | U.K. [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Related Party Transactions [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Determination price | $ / shares |  |  |  | $ 5.6457 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 4.388 |  |  |  |  |  |  |  |  |
Exchange share price | $ / shares |  |  |  | $ 6.26 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 5.17 |  |  |  |  |  |  |  |  |
Number of LPU issued on exchangeable |  |  |  | $ 137,845 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 720,000 |  |  |  |  |  |  |  |  |
Number of PLPU share issued for non exchangeable | shares |  |  |  | 9,495 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 63,814 |  |  |  |  |  |  |  |  |
Payment of witholding tax rate for common stock issue |  |  |  | $ 53,606 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 280,002 |  |  |  |  |  |  |  |  |
Number of non-exchangeable LPU redemption | shares |  |  |  | 22,020 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 139,265 |  |  |  |  |  |  |  |  |
Mr. Lynn [Member] | U.K. [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Related Party Transactions [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Determination price | $ / shares |  |  |  | $ 4.1239 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 3.894 |  |  |  |  |  |  |  |  |
Number of non-exchangeable PSU approved redemption | shares |  |  |  | 43,131 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 750,308 |  |  |  |  |  |  |  |  |
Exchange share price | $ / shares |  |  |  | $ 6.26 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 5.17 |  |  |  |  |  |  |  |  |
Number of LPU issued on exchangeable |  |  |  | $ 270,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 3,879,092 |  |  |  |  |  |  |  |  |
Number of PLPU share issued for non exchangeable | shares |  |  |  | 25,461 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 287,888 |  |  |  |  |  |  |  |  |
Payment of witholding tax rate for common stock issue |  |  |  | $ 105,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 1,120,909 |  |  |  |  |  |  |  |  |
5.125% Senior Notes Due 2021 [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Related Party Transactions [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Principal amount of debt component |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 300,000,000.0 |  |  |  |  |  |  |  |  |  |  |  |  |  |
Stated interest rate |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 5.125% |  |  |  |  |  |  |  |  |
5.375% Senior Notes Due 2023 [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Related Party Transactions [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Principal amount of debt component |  |  |  |  |  |  |  |  | $ 450,000,000.0 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Stated interest rate |  |  |  |  |  |  |  |  | 5.375% |  |  |  |  |  |  |  |  |  |  | 5.375% | 5.375% |  |  |  |  |  |  |  |  |
Debt maturity year |  |  |  |  |  |  |  |  | 2023 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
3.750% Senior Notes Due October 1, 2024 [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Related Party Transactions [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Principal amount of debt component | $ 300,000,000.0 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Stated interest rate |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 3.75% |  |  |  |  |  |  |  |  |
Real Estate L.P. |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Related Party Transactions [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Equity method investments |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 100,000,000.0 |  |
Aqua [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Related Party Transactions [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Equity investment |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 1,700,000 | $ 1,000,000.0 |  |  |  |  |  |  |  |  |
Principal sum of loan due from related parties |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 980,000 |  |  |  |  |  |  |  |  |  |
Increase in authorization amount for loans and investments, other credit support arrangements |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 1,000,000.0 |  |  |  |  |  |
Authorization amount for loans and investments, other credit support arrangements |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 17,200,000 |  |  |  |  |  |
Maturity date of subordinated loan |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | Sep. 01, 2021 |  |  |  |  |  |  |  |  |  |
Loan Receivable, Description of Variable Rate Basis |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | three month LIBOR plus 600 basis points |  |  |  |  |  |  |  |  |  |
Loan Receivable, Basis Spread on Variable Rate |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 6.00% |  |  |  |  |  |  |  |  |  |
BGC Class B Common Stock [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Related Party Transactions [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Percentage of Distributions |  |  |  |  |  | 100.00% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Newmark [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Related Party Transactions [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of shares, held by parent | shares |  |  |  |  |  | 15,100,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Newmark [Member] | LPUs [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Related Party Transactions [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Aggregate exchangeable limited partnership units purchased | shares |  |  |  |  |  |  |  |  |  |  | 16,600,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Aggregate consideration amount |  |  |  |  |  |  |  |  |  |  | $ 242,000,000.0 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of interest units owned in limited partnership | shares |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 7,000,000.0 |  |  |  |  |  |  |  |  |  |
Class A Common Stock [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Related Party Transactions [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of shares, right to exchange from Class A to Class B common stock | shares |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 11,036,000 |  |  |  |  |  |  |  |  |
Common stock, shares issued | shares |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 358,440,000 | 341,745,000 |  |  |  |  |  |  |  |  |
Issuance of Class A common stock (net of costs), shares | shares |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 212,711 | 26,003,424 | 1,994,670 |  |  |  |  |  |  |  |
Repurchase of Class A common stock, shares | shares |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 233,172 | 788,788 | 1,386,769 |  |  |  |  |  |  |  |
Average price per share of common stock repurchased | $ / shares |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 5.30 | $ 13.23 |  |  |  |  |  |  |  |  |
Class A Common Stock [Member] | Charitable Foundation [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Related Party Transactions [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share Price | $ / shares |  |  |  |  |  |  |  | $ 11.73 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of shares repurchased from charitable foundation | shares |  |  |  |  |  |  |  | 53,368 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Class A Common Stock [Member] | Stephen M. Merkel [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Related Party Transactions [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of shares to be repurchased | shares |  | 250,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Repurchase of Class A common stock, shares | shares |  | 233,172 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Average price per share of common stock repurchased | $ / shares |  | $ 5.30 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Class A Common Stock [Member] | Mr. Lutnick [Member] | Retirement Plan [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Related Party Transactions [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share Price | $ / shares |  |  | $ 6.24 |  |  |  |  |  |  |  |  | $ 13.17 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Issuance of Class A common stock (net of costs), shares | shares |  |  | 8,980 |  |  |  |  |  |  |  |  | 7,883 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Class A Common Stock [Member] | Maximum [Member] | Mr. Lutnick [Member] | Retirement Plan [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Related Party Transactions [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Value of common stock to be issued |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 56,038 |  | $ 105,000 |  |  |
Class A Common Stock [Member] | Newmark [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Related Party Transactions [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of shares, right to exchange from Class A to Class B common stock | shares |  |  |  |  |  | 9,400,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Class A Common Stock [Member] | Newmark [Member] | LPUs [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Related Party Transactions [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share Price | $ / shares |  |  |  |  |  |  |  |  |  |  | $ 14.57 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Class A Common Stock [Member] | Newmark OpCo [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Related Party Transactions [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of shares, held by parent | shares |  |  |  |  |  | 7,000,000.0 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of shares, right to exchange from Class A to Class B common stock | shares |  |  |  |  |  | 6,900,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Class B Common Stock [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Related Party Transactions [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Common stock, shares issued | shares |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 45,884,000 | 45,884,000 |  |  |  |  |  |  |  |  |
Issuance of Class A common stock (net of costs), shares | shares |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 0 |  |  |  |  |  |  |  |  |  |
Limited Partnership Units Exchange Ratio |  |  |  |  |  |  | 1 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Class B Common Stock [Member] | Newmark [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Related Party Transactions [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of shares, right to exchange from Class A to Class B common stock | shares |  |  |  |  |  | 5,400,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Class B Units [Member] | Lucera [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Related Party Transactions [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Purchase of units | shares |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 9,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Percentage of outstanding common stock owned by parent |  |  |  |  |  |  |  |  |  |  |  |  |  | 100.00% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Newmark [Member] | Revolving Credit Facility [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Related Party Transactions [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Loans to inter company |  |  |  |  |  |  |  |  |  | $ 150,000,000.0 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Newmark [Member] | LPUs [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Related Party Transactions [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Aggregate exchangeable limited partnership units purchased | shares |  |  |  |  |  | 1,500,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Newmark [Member] | Class A Common Stock [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Related Party Transactions [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Spin-off received on per share |  |  |  |  |  | 0.463895 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Aggregate distribution of shares | shares |  |  |  |  |  | 131,900,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Common stock, shares issued | shares |  |  |  |  |  | 131,886,409 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Newmark [Member] | Class B Common Stock [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Related Party Transactions [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Spin-off received on per share |  |  |  |  |  | 0.463895 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Aggregate distribution of shares | shares |  |  |  |  |  | 21,300,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Percentage of Distributions |  |  |  |  |  | 100.00% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Common stock, shares issued | shares |  |  |  |  |  | 21,285,537 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Exchange ratio |  |  |  |  |  | 0.9400 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Tower Bridge International Services LP [Member] | BGC Partners, Inc. [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Related Party Transactions [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Company ownership of Tower Bridge |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 52.00% |  |  |  |  |  |  |  |  |  |
Tower Bridge International Services LP [Member] | Cantor [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Related Party Transactions [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Noncontrolling interest |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 48.00% |  |  |  |  |  |  |  |  |  |
Aqua [Member] | BGC Partners, Inc. [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Related Party Transactions [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Percentage of ownership interest |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 49.00% |  |  |  |  |  |  |  |  |  |
Aqua [Member] | Cantor [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Related Party Transactions [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Investment ownership percentage |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 51.00% |  |  |  |  |  |  |  |  |  |
Cantor [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Related Party Transactions [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Mark-up cost of services |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 7.50% |  |  |  |  |  |  |  |  |  |
Cantor's share of net profit in Tower Bridge |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 3,100,000 | $ 1,100,000 | $ 500,000 |  |  |  |  |  |  |  |
Recognized related party revenues |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 29,400,000 | 24,100,000 | 27,100,000 |  |  |  |  |  |  |  |
Service charges |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 59,100,000 | 52,400,000 | 43,600,000 |  |  |  |  |  |  |  |
Compensation to leased employees |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 39,800,000 | 32,200,000 | 27,800,000 |  |  |  |  |  |  |  |
Repurchase agreements |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 1,000,000.0 |  |  |  |  |  |  |  |  |
Recognition of share of FX gains (losses) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 300,000 | (1,600,000) | (2,500,000) |  |  |  |  |  |  |  |
Commissions |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 200,000 | 300,000 | 300,000 |  |  |  |  |  |  |  |
Investment in asset-backed commercial paper program |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 0 | 0 |  |  |  |  |  |  |  |  |
Investment authorization in asset-backed commercial paper program |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 350,000,000.0
Principal sum of loan due from related parties |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 150,000,000.0 |
Line of credit facility, outstanding amount |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 0 |  |  |  |  |  |  | $ 150,000,000.0 |  |
Interest income from affiliate |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 0 | 0 | 2,600,000 |  |  |  |  |  |  |  |
Reverse purchase agreement outstanding |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 0 | 0 |  |  |  |  |  |  |  |  |
Securities loaned |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 15,100,000 |  |  |  |  |  |  |  |  |
Founding partner units remaining | shares |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 1,749,347 |  |  |  |  |  |  |  |  |  |
Cantor [Member] | Revolving Credit Facility [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Related Party Transactions [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Principal amount of debt component |  |  |  |  |  |  |  |  |  | 250,000,000.0 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 400,000,000.0 |  |  |  |
Credit agreement, description |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | The BGC Credit Agreement will mature on the earlier to occur of (a) March 19, 2020, after which the maturity date of the BGC Credit Agreement will continue to be extended for successive one-year periods unless prior written notice of non-extension is given by a lending party to a borrowing party at least six months in advance of such renewal date and (b) the termination of the BGC Credit Agreement by either party pursuant to its terms. |  |  |  |  |  |  |  |  |  |
Credit agreement, interest rate description |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | The outstanding amounts under the BGC Credit Agreement will bear interest for any rate period at a per annum rate equal to the higher of BGC’s or Cantor’s short-term borrowing rate in effect at such time plus 1.00% |  |  |  |  |  |  |  |  |  |
Line of credit facility, outstanding amount |  |  |  |  |  |  |  |  |  | 150,000,000.0 |  |  |  |  |  |  |  |  |  | $ 0 | 0 |  |  |  |  |  |  |  |  |
Interest expense |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 0 | 3,900,000 |  |  |  |  |  |  |  |  |
Interest expense related discontinued operation |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 0 | 3,500,000 |  |  |  |  |  |  |  |  |
Borrowings under credit facility |  |  |  |  |  |  |  |  |  | $ 150,000,000.0 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Cantor [Member] | Lucera [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Related Party Transactions [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Recognized related party revenues |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 400,000 | 800,000 | 1,200,000 |  |  |  |  |  |  |  |
Cantor [Member] | Class B Units [Member] | Lucera [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Related Party Transactions [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Equity investment |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 24,200,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Post-closing adjustment |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 4,800,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Percentage of ownership interest |  |  |  |  |  |  |  |  |  |  |  |  |  | 20.00% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Cantor [Member] | Newmark [Member] | Class A Common Stock [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Related Party Transactions [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Common stock, shares issued | shares |  |  |  |  |  | 449,917 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
CF & Co [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Related Party Transactions [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Payment percentage of the gross proceeds from the sale of shares |  |  |  |  |  |  |  |  |  |  |  |  | 5.50% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Repurchase agreements |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 1,000,000.0 |  |  |  |  |  |  |  |  |
Issuance of Class A common stock (net of costs), shares | shares |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 900,000 | 33,800,000 |  |  |  |  |  |  |  |  |
Aggregate proceeds from issuance of common stock |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 5,300,000 | $ 447,800,000 |  |  |  |  |  |  |  |  |
Weighted-average price per share | $ / shares |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 6.17 | $ 13.26 |  |  |  |  |  |  |  |  |
Related party expenses |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 100,000 | $ 9,000,000.0 | 1,400,000 |  |  |  |  |  |  |  |
Securities loaned |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 13,900,000 | $ 15,100,000 |  |  |  |  |  |  |  |  |
Stated interest rate |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 2.45% | 2.94% |  |  |  |  |  |  |  |  |
Guarantee fees |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 100,000 | $ 100,000 | 100,000 |  |  |  |  |  |  |  |
CF & Co [Member] | 5.125% Senior Notes Due 2021 [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Related Party Transactions [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Advisory fees |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 15,000,000.0 |  |  |  |  |  |  |  |  |  |  |  |  |  |
CF & Co [Member] | 5.125% Senior Notes Due 2021 [Member] | Underwriting Fees [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Related Party Transactions [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Related party expenses |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 500,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |
CF & Co [Member] | 5.375% Senior Notes Due 2023 [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Related Party Transactions [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Advisory fees |  |  |  |  |  |  |  |  | $ 200,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
CF & Co [Member] | 5.375% Senior Notes Due 2023 [Member] | Underwriting Fees [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Related Party Transactions [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Related party expenses |  |  |  |  |  |  |  |  | 300,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
CF & Co [Member] | 3.750% Senior Notes Due October 1, 2024 [Member] | Underwriting Fees [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Related Party Transactions [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Related party expenses | 200,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
CF & Co [Member] | Securities Financing Transaction, Fair Value [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Related Party Transactions [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Securities loaned |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 13,900,000 | 15,300,000 |  |  |  |  |  |  |  |  |
CF Group Management, Inc. [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Related Party Transactions [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of shares, right to exchange from Class A to Class B common stock | shares |  |  |  |  |  |  | 712,907 |  |  |  |  |  |  |  |  |  | 34,649,693 |  |  | 23,600,000 |  |  |  |  |  |  |  |  |  |
Cantor Rights to Purchase Exchangeable Units [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Related Party Transactions [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of shares, right to exchange from Class A to Class B common stock | shares |  |  |  |  |  |  | 10,323,366 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Cantor Rights to Purchase Exchangeable Units [Member] | Maximum [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Related Party Transactions [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of shares, right to exchange from Class A to Class B common stock | shares |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 34,649,693 |  |  | 23,600,000 |  |  |  |  |  |  |  |  |  |
Cantor Rights to Purchase Exchangeable Units [Member] | Class B Common Stock [Member] | Maximum [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Related Party Transactions [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of shares, right to exchange from Class A to Class B common stock | shares |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 23,613,420 |  |  |  |  |  |  |  |  |  |
Cantor and CFGM [Member] | Class B Common Stock [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Related Party Transactions [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of shares, right to exchange from Class A to Class B common stock | shares |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 23,613,420 |  |  |  |  |  |  |  |  |  |
Cantor and Freedom International Brokerage [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Related Party Transactions [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Receivables from Freedom International Brokerage |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 1,300,000 | 1,400,000 |  |  |  |  |  |  |  |  |
Receivables from Cantor related to open derivative contracts |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 1,300,000 | 1,600,000 |  |  |  |  |  |  |  |  |
Payables to Cantor related to open derivative contracts |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 2,000,000.0 | 2,100,000 |  |  |  |  |  |  |  |  |
Payables to Cantor related to pending equity trades |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 2,300,000 | 0 |  |  |  |  |  |  |  |  |
Receivables from Cantor related to pending equity trades |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 0 |  |  |  |  |  |  |  |  |
Employee Loans [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Related Party Transactions [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Employee loans |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 315,600,000 | 216,900,000 |  |  |  |  |  |  |  |  |
Compensation expense related to employee loans |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 35,700,000 | 13,000,000.0 | 26,900,000 |  |  |  |  |  |  |  |
Interest income |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 4,800,000 | 3,600,000 | $ 2,800,000 |  |  |  |  |  |  |  |
Castle Oak | 5.125% Senior Notes Due 2021 [Member] | Underwriting Fees [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Related Party Transactions [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Related party expenses |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 18,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |
Castle Oak | 5.375% Senior Notes Due 2023 [Member] | Underwriting Fees [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Related Party Transactions [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Related party expenses |  |  |  |  |  |  |  |  | $ 41,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Castle Oak | 3.750% Senior Notes Due October 1, 2024 [Member] | Underwriting Fees [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Related Party Transactions [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Related party expenses | $ 36,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Cantor Fitzgerald Relief Fund [Member] | Accounts Payable and Accrued Liabilities |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Related Party Transactions [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Charitable contributions |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 4,000,000.0 | $ 20,000,000.0 |  |  |  |  |  |  |  |  |
Cantor Fitzgerald Relief Fund [Member] | Other Expenses [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Related Party Transactions [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Charitable contributions |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 40,000,000.0 |  |  |  |  |  |  |

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- Definition Remaining liability related to charitable contributions. + References No definition available. + Details
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- Definition Right to Purchase founding partner unit outstanding. + References No definition available. + Details
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- Definition Stock issued during period additional consideration. + References No definition available. + Details
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- Definition Stockholders distribution current exchange ratio. + References No definition available. + Details
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- Definition Amount for accounts payable to related parties. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 850 -SubTopic 10 -Section 50 -Paragraph 1 -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=6457730&loc=d3e39549-107864 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 235 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.4-08.(k)(1)) -URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03.15(5)) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03.17) -URI http://asc.fasb.org/extlink&oid=119400593&loc=d3e572229-122910 + Details
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- Definition Amount of commission revenue from buying and selling securities on behalf of customers. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 940 -SubTopic 20 -Section 05 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=68070981&loc=d3e40544-110947 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 220 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-04.13(a),(b)) -URI http://asc.fasb.org/extlink&oid=116637391&loc=SL114874048-224260 + Details
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- Definition This element represents the amount of any measurement period adjustment (as defined) realized during the reporting period to items of consideration transferred in connection with a business combination for which the initial accounting was incomplete. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 20 -Section 50 -Paragraph 4A -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=116869197&loc=SL65897772-128472 + Details
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- Definition Total number of common shares of an entity that have been sold or granted to shareholders (includes common shares that were issued, repurchased and remain in the treasury). These shares represent capital invested by the firm's shareholders and owners, and may be all or only a portion of the number of shares authorized. Shares issued include shares outstanding and shares held in the treasury. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(29)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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- Definition Face (par) amount of debt instrument at time of issuance. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 835 -SubTopic 30 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=114775744&loc=d3e28551-108399 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 835 -SubTopic 30 -Section 55 -Paragraph 8 -URI http://asc.fasb.org/extlink&oid=114775985&loc=d3e28878-108400 + Details
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- Definition Contractual interest rate for funds borrowed, under the debt agreement. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.22(a)(1)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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- Definition Amount of interest expense attributable to disposal group, including, but not limited to, discontinued operation. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 205 -SubTopic 20 -Section S99 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=26872618&loc=d3e7436-122677 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 205 -SubTopic 20 -Section 45 -Paragraph 7 -URI http://asc.fasb.org/extlink&oid=109222160&loc=d3e1063-107759 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 205 -SubTopic 20 -Section 50 -Paragraph 5B -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=109222650&loc=SL51721673-107760 Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 205 -SubTopic 20 -Section 45 -Paragraph 6 -URI http://asc.fasb.org/extlink&oid=109222160&loc=d3e1060-107759 + Details
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- Definition Number of units distributed for payment of a unit distribution to unit-holder of limited partnership (LP). + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 272 -SubTopic 10 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6373374&loc=d3e70434-108055 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 272 -SubTopic 10 -Section 50 -Paragraph 3 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=6373374&loc=d3e70478-108055 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.3-04) -URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770 + Details
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- Definition For an unclassified balance sheet, amounts due from related parties including affiliates, employees, joint ventures, officers and stockholders, immediate families thereof, and pension funds. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03.10(3)) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 235 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.4-08.(k)(1)) -URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03.3) -URI http://asc.fasb.org/extlink&oid=119400593&loc=d3e572229-122910 Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 850 -SubTopic 10 -Section 50 -Paragraph 1 -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=6457730&loc=d3e39549-107864 + Details
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- Definition The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 323 -SubTopic 10 -Section 50 -Paragraph 3 -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=114001798&loc=d3e33918-111571 + Details
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- Definition This item represents the carrying amount on the entity's balance sheet of its investment in common stock of an equity method investee. This is not an indicator of the fair value of the investment, rather it is the initial cost adjusted for the entity's share of earnings and losses of the investee, adjusted for any distributions (dividends) and other than temporary impairment (OTTI) losses recognized. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 323 -SubTopic 10 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=109237563&loc=d3e33749-111570 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 280 -SubTopic 10 -Section 50 -Paragraph 25 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=115929826&loc=d3e8813-108599 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.12) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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- Definition Expense related to distribution, servicing and underwriting fees. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 220 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-04.14) -URI http://asc.fasb.org/extlink&oid=116637391&loc=SL114874048-224260 + Details
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- Definition Amount before tax of foreign currency transaction realized gain (loss) recognized in the income statement. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 830 -SubTopic 20 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=109240200&loc=d3e30690-110894 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 830 -SubTopic 20 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6450222&loc=d3e30840-110895 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 830 -SubTopic 20 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=109240200&loc=d3e30700-110894 + Details
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- Definition Amount after tax of income (loss) from continuing operations attributable to the noncontrolling interest. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 810 -SubTopic 10 -Section 45 -Paragraph 15 -URI http://asc.fasb.org/extlink&oid=108774443&loc=SL4568447-111683 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 810 -SubTopic 10 -Section 45 -Paragraph 19 -URI http://asc.fasb.org/extlink&oid=108774443&loc=SL4569616-111683 + Details
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- Definition Amount of the cost of borrowed funds accounted for as interest expense. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 835 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=6450988&loc=d3e26243-108391 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 835 -SubTopic 30 -Section 45 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=114775744&loc=d3e28555-108399 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 280 -SubTopic 10 -Section 50 -Paragraph 22 -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=115929826&loc=d3e8736-108599 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (210.5-03(11)) -URI http://asc.fasb.org/extlink&oid=116634182&loc=SL114868664-224227 Reference 5: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 220 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-04.9) -URI http://asc.fasb.org/extlink&oid=116637391&loc=SL114874048-224260 + Details
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- Definition Amount of operating interest income, including, but not limited to, amortization and accretion of premiums and discounts on securities. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03.1(e)) -URI http://asc.fasb.org/extlink&oid=116634182&loc=SL114868664-224227 + Details
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- Definition The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(22)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03(16)) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03(16)) -URI http://asc.fasb.org/extlink&oid=119400593&loc=d3e572229-122910 + Details
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- Definition Amount of current borrowing capacity under the credit facility considering any current restrictions on the amount that could be borrowed (for example, borrowings may be limited by the amount of current assets), but without considering any amounts currently outstanding under the facility. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.19(b),22(b)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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- Definition The percentage points (also referred to as 'margin') added to the reference rate as stated in the loan agreement and used to compute the variable rate on the loans receivable. For instance, the loan agreement might state that the interest rate the borrower is obligated to pay is the London Interbank Offered Rate (LIBOR) plus three quarters (3/4) of a percentage point adjusted quarterly (each three months). LIBOR in this example is the index or reference rate, 3/4 percentage point is the margin, the reference rate plus the margin is the fully indexed rate. This element would be used to report separately the margin. + References No definition available. + Details
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- Definition Description of long-term debt arrangements, which are debt arrangements that originally require full repayment more than twelve months after issuance or greater than the normal operating cycle of the company, if longer, and disclosures pertaining to the underlying arrangements, including repayment terms, conversion features, interest rates, restrictions on assets and activities, debt covenants, and other matters important to users of the financial statements. Types of long-term debt arrangements include borrowing under notes payable, bonds payable, debentures, term loans, and other contractual obligations for payment. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section 50 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=109259400&loc=d3e21475-112644 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.22) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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- Definition The equity interest of noncontrolling shareholders, partners or other equity holders in consolidated entity. + References No definition available. + Details
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