Share-Based and Other Deferred Compensation - Additional information (Detail) - USD ($) $ / shares in Units, shares in Thousands	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014	Dec. 31, 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Management Basis EBIT Margin (as a percent)	15.00%
Management Basis EBIT	$ 32,800,000
Class H Interests Performance Period (in years)			3 years
Expense Related To Separation Benefits	2,188,000	$ 1,198,000	$ 3,795,000	$ 4,589,000
Cash Payments Related To Separation Benefits	321,000	521,000	$ 1,531,000	3,002,000
Long Term Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Long Term Incentive Plan Performance period (in years)			4 years
Long Term Incentive Plan Payment period (in years)			2 years
Deferred compensation arrangement compensation expense	1,530,000	1,032,000	$ 3,043,000	2,143,000
Employee Loans [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Deferred compensation arrangement compensation expense	4,371,000	3,003,000	$ 8,951,000	5,650,000
Requisite service period (in years)			1 year
Maximum contractual term (in years)			5 years
Unamortized deferred compensation	23,579,000		$ 23,579,000
Equity Grants [Member] | Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted average grant date fair value (in dollars per share)			$ 48.41
Equity Grants [Member] | Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted average grant date fair value (in dollars per share)			$ 54.42
Equity Grants [Member] | Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expense related to Service-based Award	27,465,000	24,847,000	$ 54,960,000	47,091,000
Class H Interests [Member] | Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Management Basis EBIT Margin (as a percent)			7.00%
Management Basis EBIT			$ 8,000,000
Class H Interests [Member] | Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Management Basis EBIT Margin (as a percent)			17.00%
Management Basis EBIT			$ 48,000,000
Class G Interests [Member] | Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Management Basis EBIT Margin (as a percent)			12.00%
Class G Interests [Member] | Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Management Basis EBIT Margin (as a percent)			16.00%
Restricted Stock Units (RSUs) [Member] | Equity Grants [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares issued during period (in shares)			2,444
Shares vested during period (in shares)			2,096
Shares forfeited during period (in shares)			144
Deferred Cash Program [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Deferred compensation, vesting period (in years)			4 years
Compensation expense related to deferred compensation programs	448,000	946,000	$ 1,008,000	1,840,000
Acquisition Related [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expense related to acquisition related awards	622,000	1,757,000	1,237,000	3,998,000
Compensation expense related to deferred cash consideration	330,000	$ 767,000	301,000	$ 1,699,000
Special Charges [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expense Related To Separation Benefits	(102,000)		1,863,000
Cash Payments Related To Separation Benefits	487,000		487,000
Class E LP Units [Member] | Evercore ISI [Member] | Acquisition Related [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expense related to acquisition related awards	4,893,000		9,961,000
Class E LP Units [Member] | Evercore ISI [Member] | Vested LP Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Grant Of LP Units (in units)					710
Class E LP Units [Member] | Evercore ISI [Member] | Unvested LP Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Grant Of LP Units (in units)					710
Class G Interests [Member] | Evercore ISI [Member] | Vested LP Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Grant Of LP Units (in units)					538
Class G Interests [Member] | Evercore ISI [Member] | Unvested LP Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Grant Of LP Units (in units)					540
Class H Interests [Member] | Evercore ISI [Member] | Vested LP Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Grant Of LP Units (in units)					2,044
Class H Interests [Member] | Evercore ISI [Member] | Unvested LP Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Grant Of LP Units (in units)					2,051
Class G And H Interests [Member] | Evercore ISI [Member] | Acquisition Related [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expense related to acquisition related awards	$ 13,170,000		$ 33,313,000