Regulatory Authorities - Additional Information (Detail) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013
EGL [Member]
Regulatory Authorities [Line Items]
Alternative Net Capital Requirement	$ 250,000
Net Capital	74,080,000	30,480,000
Alternative excess net capital	73,830,000	30,230,000
International Strategy & Investment Group LLC [Member]
Regulatory Authorities [Line Items]
Alternative Net Capital Requirement	250,000
Net Capital	7,548,000
Alternative excess net capital	7,298,000
Evercore Trust Company [Member]
Regulatory Authorities [Line Items]
Tier One Capital	5,000,000
Minimum liquid assets, amount	3,500,000
Coverage of operating expenses (in days)	90 days
Collateral held in a segregated account at a third-party depository institution	$ 10,000,000