CONSOLIDATED STATEMENTS OF CHANGES IN EQUITY - USD ($) $ in Thousands	Total	Additional Paid-in Capital	Treasury Stock	Retained Earnings	Accumulated Other Comprehensive Income (Loss)	Noncontrolling Interests	Class A Common Stock Common Stock	Class B Common Stock Common Stock	Contingent Class A Common Stock Common Stock
Balance at beginning of period at Dec. 31, 2020	$ 921,147	$ 351,450	$ (40,531)	$ 342,764	$ (2,094)	$ 266,098	$ 1,676	$ 212	$ 1,572
Increase (Decrease) in Stockholders' Equity
Consolidated net income	978,134			750,728		227,406
Foreign currency translation adjustments	(832)				(637)	(195)
Cantor purchase of Cantor units from Newmark Holdings upon redemption/exchange of FPU's	6,898					6,898
Dividends to common stockholders	(7,631)			(7,631)
Non-Controlling interest in Deskeo	13,464					13,464
Issuance of Class A common stock for acquisition	3,000	2,577				423
Dividend on EPUs	0			(6,200)		6,200
Earnings distributions to limited partnership interests and other noncontrolling interests	1,805					1,805
Grant of exchangeability, redemption and issuance of Class A common stock	165,644	104,121				61,259	264
Contributions of capital to and from Cantor for equity-based compensation	28,012	19,348				8,664
Repurchase of Class A common stock	(290,184)		(249,643)			(40,541)
Restricted stock units compensation	12,132	9,951				2,181
Redemption of EPU’s	(167,396)					(167,396)
Balance at end of period at Dec. 31, 2021	1,664,193	487,447	(290,174)	1,079,661	(2,731)	386,266	1,940	212	1,572
Increase (Decrease) in Stockholders' Equity
Consolidated net income	112,545			83,275		29,270
Foreign currency translation adjustments	(11,033)				(9,258)	(1,775)
Cantor purchase of Cantor units from Newmark Holdings upon redemption/exchange of FPU's	1,582					1,582
Dividends to common stockholders	(17,930)			(17,930)
Earnings distributions to limited partnership interests and other noncontrolling interests	(51,006)					(51,006)
Grant of exchangeability, redemption and issuance of Class A common stock	103,180	82,161				22,520	71		(1,572)
Contributions of capital to and from Cantor for equity-based compensation	2,568	2,097				471
Repurchase of Class A common stock	(294,802)		(248,438)			(46,364)
Restricted stock units compensation	15,568	13,004				2,564
Balance at end of period at Dec. 31, 2022	1,524,865	584,709	(538,612)	1,145,006	(11,989)	343,528	2,011	212	$ 0
Increase (Decrease) in Stockholders' Equity
Consolidated net income	62,375			42,575		19,800
Foreign currency translation adjustments	9,112				7,434	1,678
Cantor purchase of Cantor units from Newmark Holdings upon redemption/exchange of FPU's	1,760					1,760
Dividends to common stockholders	(20,906)			(20,906)
Purchase of non-controlling interest	(21,946)	(3,462)				(18,484)
Earnings distributions to limited partnership interests and other noncontrolling interests	(42,107)					(42,107)
Grant of exchangeability, redemption and issuance of Class A common stock	84,610	61,351				23,175	84
Contributions of capital to and from Cantor for equity-based compensation	(2,782)	(2,182)				(600)
Repurchase of Class A common stock	(37,429)		(30,623)			(6,806)
Restricted stock units compensation	21,130	17,320				3,810
Balance at end of period at Dec. 31, 2023	$ 1,578,682	$ 657,736	$ (569,235)	$ 1,166,675	$ (4,555)	$ 325,754	$ 2,095	$ 212