COMMITMENTS AND CONTINGENCIES (Detail) - USD ($)	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015	Dec. 31, 2014	Dec. 31, 2015
Contingencies And Commitments [Line Items]
Accrued incentives (fund level)	$ 1,520,994,000		$ 1,520,994,000			$ 1,540,469,000
Compensation expense related to accrued incentives (fund level)	751,874,000		751,874,000			750,077,000
Capital commitments	516,600,000		516,600,000			469,400,000
Consolidated Funds
Contingencies And Commitments [Line Items]
Aggregate potential credit and investment commitments	2,900,000		$ 2,900,000			1,300,000,000
Highstar Capital
Contingencies And Commitments [Line Items]
Contingent consideration					$ 60,000,000
Performance period (in years)			7 years		7 years
Contingent consideration	25,000,000		$ 25,000,000			28,500,000
Contingent consideration income	2,900,000		3,500,000
Contingent consideration expense		$ 700,000		$ 1,500,000
Financial Guarantee | Consolidated Funds
Contingencies And Commitments [Line Items]
Other commitment	$ 0		$ 0			$ 142,400,000