Revenues Derived from Clients and Private Equity Funds by Geographical Areas (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended				9 Months Ended
	Sep. 30, 2013		Sep. 30, 2012		Sep. 30, 2013		Sep. 30, 2012
Segment Reporting Information [Line Items]
Net revenue	$ 188,213	[1]	$ 154,284	[1]	$ 549,576	[1]	$ 433,005	[1]
United States [Member]
Segment Reporting Information [Line Items]
Net revenue	131,499		114,018		379,950		315,085
Europe And Other [Member]
Segment Reporting Information [Line Items]
Net revenue	37,465		30,860		112,331		90,491
Latin America [Member]
Segment Reporting Information [Line Items]
Net revenue	$ 19,249		$ 9,406		$ 57,295		$ 27,429

[1] Excludes Other Revenue and Interest Expense.