Noncontrolling Interest - Changes In Noncontrolling Interest (Details) - USD ($) $ in Thousands	3 Months Ended								9 Months Ended	12 Months Ended
	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Sep. 30, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Stockholders' Equity Attributable to Noncontrolling Interest [Roll Forward]
Beginning balance				$ 256,033						$ 256,033
Comprehensive Income (Loss):
Net Income Attributable to Noncontrolling Interest	$ 18,013	$ 14,171	$ 7,693	13,876	$ 16,530	$ 12,588	$ 9,506	$ 2,360		53,753	$ 40,984	$ 14,827
Total Comprehensive Income										57,128	37,247	10,941
Total Other Items										(36,879)	(50,047)	(38,620)
Ending balance	252,404				256,033					252,404	256,033
GCP III [Member]
Comprehensive Income (Loss):
Deconsolidation of Noncontrolling Interest									$ (5,808)
Noncontrolling Interest [Member]
Stockholders' Equity Attributable to Noncontrolling Interest [Roll Forward]
Beginning balance				$ 256,033				$ 202,664	$ 202,664	256,033	202,664	160,952
Comprehensive Income (Loss):
Net Income Attributable to Noncontrolling Interest										53,753	40,984	14,827
Other Comprehensive Income (Loss)										3,375	(3,737)	(3,886)
Total Comprehensive Income										57,128	37,247	10,941
Evercore LP Units Purchased or Converted into Class A Shares										(47,263)	(16,480)	(12,012)
Amortization and Vesting of LP Units/Interests										14,922	81,392	82,734
Distributions to Noncontrolling Interests										(36,374)	(38,154)	(23,723)
Issuance of Noncontrolling Interest										8,460	885	594
Purchase of Noncontrolling Interest										(281)	(5,225)	0
Other, net										(221)	(488)	(732)
Total Other Items										(28,416)	(48,790)	(39,951)
Ending balance	$ 252,404				$ 256,033					252,404	256,033	202,664
Noncontrolling Interest [Member] | GCP III [Member]
Comprehensive Income (Loss):
Deconsolidation of Noncontrolling Interest										0	(5,808)	0
Noncontrolling Interest [Member] | Atalanta Sosnoff [Member]
Comprehensive Income (Loss):
Deconsolidation of Noncontrolling Interest										$ 0	$ 0	$ (16,090)