Performance Fees Allocated to Funds (Detail) (USD $) In Thousands, unless otherwise specified	6 Months Ended
	Jun. 30, 2012
Schedule of Performance Fees and Allocations to the General Partner [Line Items]
Performance Fees, December 31, 2011	$ 1,889,152
Performance Fees Allocated as a Result of Changes in Fund Fair Values	489,137
Foreign Exchange Loss	(3,094)
Fund Cash Distributions	(103,905)
Performance Fees, June 30, 2012	2,271,290
Private Equity
Schedule of Performance Fees and Allocations to the General Partner [Line Items]
Performance Fees, December 31, 2011	620,359
Performance Fees Allocated as a Result of Changes in Fund Fair Values	(14,305)
Fund Cash Distributions	(3,349)
Performance Fees, June 30, 2012	602,705
Real Estate
Schedule of Performance Fees and Allocations to the General Partner [Line Items]
Performance Fees, December 31, 2011	943,859
Performance Fees Allocated as a Result of Changes in Fund Fair Values	388,089
Foreign Exchange Loss	(3,094)
Fund Cash Distributions	(19,110)
Performance Fees, June 30, 2012	1,309,744
Hedge Funds
Schedule of Performance Fees and Allocations to the General Partner [Line Items]
Performance Fees, December 31, 2011	1,858
Performance Fees Allocated as a Result of Changes in Fund Fair Values	10,375
Fund Cash Distributions	(3,843)
Performance Fees, June 30, 2012	8,390
Credit Businesses
Schedule of Performance Fees and Allocations to the General Partner [Line Items]
Performance Fees, December 31, 2011	323,076
Performance Fees Allocated as a Result of Changes in Fund Fair Values	104,978
Fund Cash Distributions	(77,603)
Performance Fees, June 30, 2012	$ 350,451