Revenues Derived from Clients and Private Equity Funds by Geographical Areas (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2013		Mar. 31, 2012
Segment Reporting Information [Line Items]
Net revenue	$ 152,922	[1]	$ 104,259	[1]
United States
Segment Reporting Information [Line Items]
Net revenue	90,856	[1]	69,661	[1]
Europe And Other
Segment Reporting Information [Line Items]
Net revenue	39,471	[1]	24,322	[1]
Latin America
Segment Reporting Information [Line Items]
Net revenue	$ 22,595	[1]	$ 10,276	[1]

[1] Excludes Other Revenue and Interest Expense.