Performance Fees Allocated to Funds (Detail) $ in Thousands	12 Months Ended
	Dec. 31, 2018 USD ($)
Schedule of Performance Fees and Allocations to the General Partner [Line Items]
Beginning Balance	$ 24,434,049
Ending Balance	20,377,031
Performance Fees
Schedule of Performance Fees and Allocations to the General Partner [Line Items]
Beginning Balance	5,328,280
Performance Allocations as a Result of Changes in Fund Fair Values	2,464,931
Foreign Exchange Loss	(27,051)
Fund Distributions	(1,882,236)
Ending Balance	5,883,924
Real Estate Segment | Performance Fees
Schedule of Performance Fees and Allocations to the General Partner [Line Items]
Beginning Balance	2,859,307
Performance Allocations as a Result of Changes in Fund Fair Values	991,133
Foreign Exchange Loss	(27,051)
Fund Distributions	(970,128)
Ending Balance	2,853,261
Private Equity Segment | Performance Fees
Schedule of Performance Fees and Allocations to the General Partner [Line Items]
Beginning Balance	1,916,971
Performance Allocations as a Result of Changes in Fund Fair Values	1,456,671
Fund Distributions	(731,523)
Ending Balance	2,642,119
Hedge Fund Solutions Segment | Performance Fees
Schedule of Performance Fees and Allocations to the General Partner [Line Items]
Beginning Balance	13,802
Performance Allocations as a Result of Changes in Fund Fair Values	33,185
Fund Distributions	(24,066)
Ending Balance	22,921
Credit Segment | Performance Fees
Schedule of Performance Fees and Allocations to the General Partner [Line Items]
Beginning Balance	538,200
Performance Allocations as a Result of Changes in Fund Fair Values	(16,058)
Fund Distributions	(156,519)
Ending Balance	$ 365,623