Noncontrolling Interest Noncontrolling Interest - Schedule of Noncontrolling Interest (Details)	Sep. 30, 2017	Sep. 30, 2016
Evercore LP [Member]
Noncontrolling Interest [Line Items]
Noncontrolling Interest (as a percent)	13.00%	14.00%
Evercore Wealth Management L.L.C. (EWM) [Member]
Noncontrolling Interest [Line Items]
Noncontrolling Interest (as a percent)	38.00%	38.00%
Private Capital Advisory L.P. (PCA) [Member]
Noncontrolling Interest [Line Items]
Noncontrolling Interest (as a percent)	26.00%	39.00%