FAIR VALUE - Summary of Valuation Techniques and Quantitative Information (Detail) $ in Thousands	9 Months Ended		12 Months Ended
	Sep. 30, 2015 USD ($) loan investment	Sep. 30, 2014 investment	Dec. 31, 2014 USD ($)	Feb. 28, 2014 USD ($)
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Total investments, at fair value	$ 47,684,422		$ 46,533,799	$ 312,900
Number of investments that changed valuation technique | investment	10
Credit-oriented investments:
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Number of investments that changed valuation technique | investment	3	1
Credit-oriented investments: | Discounted cash flow
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Number of investments that changed valuation technique | investment	1
Credit-oriented investments: | Market approach (comparable companies)
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Number of investments that changed valuation technique | investment	1	1
Number of loans | loan	10
Equity securities:
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Number of investments that changed valuation technique | investment	1	1
Equity securities: | Market approach (comparable companies)
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Number of investments that changed valuation technique | investment		1
Equity securities: | Recent market information
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Number of investments that changed valuation technique | investment	1
Real estate-oriented investments:
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Number of investments that changed valuation technique | investment	1	1
Consolidated Funds
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Total investments, at fair value	$ 47,684,422		46,533,799
Consolidated Funds | Level III
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Total investments, at fair value	28,254,357		26,291,698
Consolidated Funds | Level III | Credit-oriented investments: | Consumer discretionary | Discounted cash flow
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Total investments, at fair value	$ 261,456		$ 164,401
Consolidated Funds | Level III | Credit-oriented investments: | Consumer discretionary | Discounted cash flow | Minimum
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Discount rate (as a percent)	5.00%		5.00%
Consolidated Funds | Level III | Credit-oriented investments: | Consumer discretionary | Discounted cash flow | Maximum
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Discount rate (as a percent)	14.00%		12.00%
Consolidated Funds | Level III | Credit-oriented investments: | Consumer discretionary | Discounted cash flow | Weighted Average
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Discount rate (as a percent)	12.00%		11.00%
Consolidated Funds | Level III | Credit-oriented investments: | Consumer discretionary | Market approach (comparable companies)
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Total investments, at fair value	$ 465,696		$ 487,784
Consolidated Funds | Level III | Credit-oriented investments: | Consumer discretionary | Market approach (comparable companies) | Minimum
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Earnings multiple	3		3
Consolidated Funds | Level III | Credit-oriented investments: | Consumer discretionary | Market approach (comparable companies) | Maximum
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Earnings multiple	8		10
Consolidated Funds | Level III | Credit-oriented investments: | Consumer discretionary | Market approach (comparable companies) | Weighted Average
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Earnings multiple	6		5
Consolidated Funds | Level III | Credit-oriented investments: | Consumer discretionary | Recent transaction price
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Total investments, at fair value	$ 110,104		$ 133,410
Consolidated Funds | Level III | Credit-oriented investments: | Consumer discretionary | Recent market information
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Total investments, at fair value	120,922		119,219
Consolidated Funds | Level III | Credit-oriented investments: | Financials | Discounted cash flow
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Total investments, at fair value	$ 529,756		$ 280,827
Consolidated Funds | Level III | Credit-oriented investments: | Financials | Discounted cash flow | Minimum
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Discount rate (as a percent)	6.00%		9.00%
Consolidated Funds | Level III | Credit-oriented investments: | Financials | Discounted cash flow | Maximum
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Discount rate (as a percent)	14.00%		14.00%
Consolidated Funds | Level III | Credit-oriented investments: | Financials | Discounted cash flow | Weighted Average
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Discount rate (as a percent)	11.00%		12.00%
Consolidated Funds | Level III | Credit-oriented investments: | Financials | Recent transaction price
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Total investments, at fair value	$ 250,237		$ 228,804
Consolidated Funds | Level III | Credit-oriented investments: | Financials | Recent market information
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Total investments, at fair value	177,634		55,472
Consolidated Funds | Level III | Credit-oriented investments: | Financials | Market approach (value of underlying assets)
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Total investments, at fair value	$ 247,235		$ 205,639
Consolidated Funds | Level III | Credit-oriented investments: | Financials | Market approach (value of underlying assets) | Minimum
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Underlying asset multiple	1.1		0.9
Consolidated Funds | Level III | Credit-oriented investments: | Financials | Market approach (value of underlying assets) | Maximum
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Underlying asset multiple	1.5		1.1
Consolidated Funds | Level III | Credit-oriented investments: | Financials | Market approach (value of underlying assets) | Weighted Average
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Underlying asset multiple	1.2		1
Consolidated Funds | Level III | Credit-oriented investments: | Industrials | Discounted cash flow
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Total investments, at fair value	$ 207,569		$ 240,935
Consolidated Funds | Level III | Credit-oriented investments: | Industrials | Discounted cash flow | Minimum
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Discount rate (as a percent)	500.00%		5.00%
Consolidated Funds | Level III | Credit-oriented investments: | Industrials | Discounted cash flow | Maximum
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Discount rate (as a percent)	1500.00%		20.00%
Consolidated Funds | Level III | Credit-oriented investments: | Industrials | Discounted cash flow | Weighted Average
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Discount rate (as a percent)	0.00%		13.00%
Consolidated Funds | Level III | Credit-oriented investments: | Industrials | Market approach (comparable companies)
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Total investments, at fair value	$ 7,658		$ 13,358
Consolidated Funds | Level III | Credit-oriented investments: | Industrials | Market approach (comparable companies) | Minimum
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Earnings multiple	5		3
Consolidated Funds | Level III | Credit-oriented investments: | Industrials | Market approach (comparable companies) | Maximum
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Earnings multiple	8		8
Consolidated Funds | Level III | Credit-oriented investments: | Industrials | Market approach (comparable companies) | Weighted Average
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Earnings multiple	7		7
Consolidated Funds | Level III | Credit-oriented investments: | Industrials | Recent transaction price
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Total investments, at fair value	$ 21,100		$ 121,888
Consolidated Funds | Level III | Credit-oriented investments: | Industrials | Recent market information
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Total investments, at fair value	21,945		113,500
Consolidated Funds | Level III | Credit-oriented investments: | Industrials | Market approach (value of underlying assets)
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Total investments, at fair value	$ 239,945		$ 83,020
Consolidated Funds | Level III | Credit-oriented investments: | Industrials | Market approach (value of underlying assets) | Minimum
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Underlying asset multiple	0.7		0.9
Consolidated Funds | Level III | Credit-oriented investments: | Industrials | Market approach (value of underlying assets) | Maximum
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Underlying asset multiple	1.0		1.1
Consolidated Funds | Level III | Credit-oriented investments: | Industrials | Market approach (value of underlying assets) | Weighted Average
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Underlying asset multiple	0.9		1
Consolidated Funds | Level III | Credit-oriented investments: | Industrials | Discounted cash flow / Sales approach
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Total investments, at fair value	$ 55,679		$ 206,763
Consolidated Funds | Level III | Credit-oriented investments: | Industrials | Discounted cash flow / Sales approach | Minimum
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Discount rate / Market transactions (as a percent)	11.00%		10.00%
Consolidated Funds | Level III | Credit-oriented investments: | Industrials | Discounted cash flow / Sales approach | Maximum
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Discount rate / Market transactions (as a percent)	13.00%		14.00%
Consolidated Funds | Level III | Credit-oriented investments: | Industrials | Discounted cash flow / Sales approach | Weighted Average
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Discount rate / Market transactions (as a percent)	12.00%		12.00%
Consolidated Funds | Level III | Credit-oriented investments: | Information technology | Discounted cash flow
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Total investments, at fair value	$ 182,868
Consolidated Funds | Level III | Credit-oriented investments: | Information technology | Discounted cash flow | Minimum
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Discount rate (as a percent)	6.00%
Consolidated Funds | Level III | Credit-oriented investments: | Information technology | Discounted cash flow | Maximum
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Discount rate (as a percent)	13.00%
Consolidated Funds | Level III | Credit-oriented investments: | Information technology | Discounted cash flow | Weighted Average
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Discount rate (as a percent)	12.00%
Consolidated Funds | Level III | Credit-oriented investments: | Information technology | Market approach (comparable companies)
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Total investments, at fair value	$ 143,705
Consolidated Funds | Level III | Credit-oriented investments: | Information technology | Market approach (comparable companies) | Minimum
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Earnings multiple	6
Consolidated Funds | Level III | Credit-oriented investments: | Information technology | Market approach (comparable companies) | Maximum
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Earnings multiple	8
Consolidated Funds | Level III | Credit-oriented investments: | Information technology | Market approach (comparable companies) | Weighted Average
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Earnings multiple	7
Consolidated Funds | Level III | Credit-oriented investments: | Information technology | Recent transaction price
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Total investments, at fair value	$ 61,856
Consolidated Funds | Level III | Credit-oriented investments: | Information technology | Recent market information
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Total investments, at fair value	71,245
Consolidated Funds | Level III | Credit-oriented investments: | Materials | Discounted cash flow
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Total investments, at fair value	$ 454,015		$ 77,008
Consolidated Funds | Level III | Credit-oriented investments: | Materials | Discounted cash flow | Minimum
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Discount rate (as a percent)	11.00%		11.00%
Consolidated Funds | Level III | Credit-oriented investments: | Materials | Discounted cash flow | Maximum
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Discount rate (as a percent)	14.00%		13.00%
Consolidated Funds | Level III | Credit-oriented investments: | Materials | Discounted cash flow | Weighted Average
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Discount rate (as a percent)	13.00%		12.00%
Consolidated Funds | Level III | Credit-oriented investments: | Materials | Market approach (comparable companies)
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Total investments, at fair value	$ 134,581		$ 250,803
Consolidated Funds | Level III | Credit-oriented investments: | Materials | Market approach (comparable companies) | Minimum
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Earnings multiple	7		6
Consolidated Funds | Level III | Credit-oriented investments: | Materials | Market approach (comparable companies) | Maximum
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Earnings multiple	8		8
Consolidated Funds | Level III | Credit-oriented investments: | Materials | Market approach (comparable companies) | Weighted Average
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Earnings multiple	7		7
Consolidated Funds | Level III | Credit-oriented investments: | Materials | Recent transaction price
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Total investments, at fair value	$ 7,198		$ 64,490
Consolidated Funds | Level III | Credit-oriented investments: | Materials | Recent market information
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Total investments, at fair value	5,969
Consolidated Funds | Level III | Credit-oriented investments: | Materials | Discounted cash flow / Sales approach
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Total investments, at fair value			$ 189,081
Consolidated Funds | Level III | Credit-oriented investments: | Materials | Discounted cash flow / Sales approach | Minimum
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Discount rate / Market transactions (as a percent)			15.00%
Consolidated Funds | Level III | Credit-oriented investments: | Materials | Discounted cash flow / Sales approach | Maximum
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Discount rate / Market transactions (as a percent)			17.00%
Consolidated Funds | Level III | Credit-oriented investments: | Materials | Discounted cash flow / Sales approach | Weighted Average
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Discount rate / Market transactions (as a percent)			16.00%
Consolidated Funds | Level III | Credit-oriented investments: | Other | Discounted cash flow
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Total investments, at fair value	$ 395,972		$ 449,065
Consolidated Funds | Level III | Credit-oriented investments: | Other | Discounted cash flow | Minimum
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Discount rate (as a percent)	5.00%		5.00%
Consolidated Funds | Level III | Credit-oriented investments: | Other | Discounted cash flow | Maximum
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Discount rate (as a percent)	14.00%		13.00%
Consolidated Funds | Level III | Credit-oriented investments: | Other | Discounted cash flow | Weighted Average
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Discount rate (as a percent)	11.00%		11.00%
Consolidated Funds | Level III | Credit-oriented investments: | Other | Market approach (comparable companies)
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Total investments, at fair value	$ 23,013		$ 376,237
Consolidated Funds | Level III | Credit-oriented investments: | Other | Market approach (comparable companies) | Minimum
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Earnings multiple	6		7
Consolidated Funds | Level III | Credit-oriented investments: | Other | Market approach (comparable companies) | Maximum
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Earnings multiple	8		8
Consolidated Funds | Level III | Credit-oriented investments: | Other | Market approach (comparable companies) | Weighted Average
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Earnings multiple	7		8
Consolidated Funds | Level III | Credit-oriented investments: | Other | Recent transaction price
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Total investments, at fair value	$ 178,480		$ 123,842
Consolidated Funds | Level III | Credit-oriented investments: | Other | Recent market information
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Total investments, at fair value	145,615		310,084
Consolidated Funds | Level III | Credit-oriented investments: | Other | Market approach (value of underlying assets)
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Total investments, at fair value	$ 169,003
Consolidated Funds | Level III | Credit-oriented investments: | Other | Market approach (value of underlying assets) | Minimum
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Underlying asset multiple	0.9
Consolidated Funds | Level III | Credit-oriented investments: | Other | Market approach (value of underlying assets) | Maximum
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Underlying asset multiple	1.1
Consolidated Funds | Level III | Credit-oriented investments: | Other | Market approach (value of underlying assets) | Weighted Average
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Underlying asset multiple	1
Consolidated Funds | Level III | Credit-oriented investments: | Energy | Recent market information
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Total investments, at fair value	$ 47,713
Consolidated Funds | Level III | Equity securities: | Financials | Recent transaction price
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Total investments, at fair value	242,602		171,844
Consolidated Funds | Level III | Equity securities: | Financials | Recent market information
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Total investments, at fair value	153,457		140,804
Consolidated Funds | Level III | Equity securities: | Financials | Market approach (value of underlying assets)
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Total investments, at fair value	$ 971,070		$ 646,720
Consolidated Funds | Level III | Equity securities: | Financials | Market approach (value of underlying assets) | Minimum
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Underlying asset multiple	1		1
Consolidated Funds | Level III | Equity securities: | Financials | Market approach (value of underlying assets) | Maximum
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Underlying asset multiple	1.5		1.1
Consolidated Funds | Level III | Equity securities: | Financials | Market approach (value of underlying assets) | Weighted Average
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Underlying asset multiple	1.3		1
Consolidated Funds | Level III | Equity securities: | Financials | Discounted cash flow / Sales approach
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Total investments, at fair value			$ 116,328
Consolidated Funds | Level III | Equity securities: | Financials | Discounted cash flow / Sales approach | Minimum
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Discount rate / Market transactions (as a percent)			6.00%
Consolidated Funds | Level III | Equity securities: | Financials | Discounted cash flow / Sales approach | Maximum
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Discount rate / Market transactions (as a percent)			8.00%
Consolidated Funds | Level III | Equity securities: | Financials | Discounted cash flow / Sales approach | Weighted Average
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Discount rate / Market transactions (as a percent)			7.00%
Consolidated Funds | Level III | Equity securities: | Industrials | Discounted cash flow
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Total investments, at fair value	$ 37,130
Consolidated Funds | Level III | Equity securities: | Industrials | Discounted cash flow | Minimum
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Discount rate (as a percent)	10.00%
Consolidated Funds | Level III | Equity securities: | Industrials | Discounted cash flow | Maximum
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Discount rate (as a percent)	12.00%
Consolidated Funds | Level III | Equity securities: | Industrials | Discounted cash flow | Weighted Average
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Discount rate (as a percent)	11.00%
Consolidated Funds | Level III | Equity securities: | Industrials | Market approach (comparable companies)
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Total investments, at fair value	$ 1,898,275		$ 2,086,026
Consolidated Funds | Level III | Equity securities: | Industrials | Market approach (comparable companies) | Minimum
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Earnings multiple	5		3
Consolidated Funds | Level III | Equity securities: | Industrials | Market approach (comparable companies) | Maximum
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Earnings multiple	11		15
Consolidated Funds | Level III | Equity securities: | Industrials | Market approach (comparable companies) | Weighted Average
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Earnings multiple	8		9
Consolidated Funds | Level III | Equity securities: | Industrials | Recent transaction price
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Total investments, at fair value	$ 277,231		$ 100,655
Consolidated Funds | Level III | Equity securities: | Industrials | Recent market information
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Total investments, at fair value	181,107		397,377
Consolidated Funds | Level III | Equity securities: | Industrials | Market approach (value of underlying assets)
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Total investments, at fair value	$ 1,451,622		$ 2,313,549
Consolidated Funds | Level III | Equity securities: | Industrials | Market approach (value of underlying assets) | Minimum
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Underlying asset multiple	0.9		1
Consolidated Funds | Level III | Equity securities: | Industrials | Market approach (value of underlying assets) | Maximum
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Underlying asset multiple	1.1		1.2
Consolidated Funds | Level III | Equity securities: | Industrials | Market approach (value of underlying assets) | Weighted Average
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Underlying asset multiple	1		1
Consolidated Funds | Level III | Equity securities: | Materials | Market approach (comparable companies)
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Total investments, at fair value	$ 1,255,972		$ 1,154,908
Consolidated Funds | Level III | Equity securities: | Materials | Market approach (comparable companies) | Minimum
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Earnings multiple	7		4
Consolidated Funds | Level III | Equity securities: | Materials | Market approach (comparable companies) | Maximum
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Earnings multiple	9		11
Consolidated Funds | Level III | Equity securities: | Materials | Market approach (comparable companies) | Weighted Average
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Earnings multiple	8		8
Consolidated Funds | Level III | Equity securities: | Materials | Recent transaction price
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Total investments, at fair value	$ 25,133		$ 70,123
Consolidated Funds | Level III | Equity securities: | Materials | Recent market information
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Total investments, at fair value			1,477
Consolidated Funds | Level III | Equity securities: | Other | Market approach (comparable companies)
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Total investments, at fair value	$ 2,260,092		$ 1,371,935
Consolidated Funds | Level III | Equity securities: | Other | Market approach (comparable companies) | Minimum
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Earnings multiple	3		4
Consolidated Funds | Level III | Equity securities: | Other | Market approach (comparable companies) | Maximum
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Earnings multiple	12		12
Consolidated Funds | Level III | Equity securities: | Other | Market approach (comparable companies) | Weighted Average
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Earnings multiple	8		8
Consolidated Funds | Level III | Equity securities: | Other | Recent transaction price
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Total investments, at fair value	$ 222,512		$ 55,769
Consolidated Funds | Level III | Equity securities: | Other | Recent market information
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Total investments, at fair value	152,080		151,933
Consolidated Funds | Level III | Equity securities: | Other | Other
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Total investments, at fair value	271,089
Consolidated Funds | Level III | Equity securities: | Energy | Discounted cash flow
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Total investments, at fair value			$ 47,524
Consolidated Funds | Level III | Equity securities: | Energy | Discounted cash flow | Minimum
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Discount rate (as a percent)			10.00%
Consolidated Funds | Level III | Equity securities: | Energy | Discounted cash flow | Maximum
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Discount rate (as a percent)			12.00%
Consolidated Funds | Level III | Equity securities: | Energy | Discounted cash flow | Weighted Average
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Discount rate (as a percent)			11.00%
Consolidated Funds | Level III | Equity securities: | Energy | Market approach (comparable companies)
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Total investments, at fair value	$ 776,064		$ 1,045,233
Consolidated Funds | Level III | Equity securities: | Energy | Market approach (comparable companies) | Minimum
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Earnings multiple	7		5
Consolidated Funds | Level III | Equity securities: | Energy | Market approach (comparable companies) | Maximum
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Earnings multiple	18		18
Consolidated Funds | Level III | Equity securities: | Energy | Market approach (comparable companies) | Weighted Average
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Earnings multiple	15		12
Consolidated Funds | Level III | Equity securities: | Energy | Recent transaction price
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Total investments, at fair value	$ 64,524		$ 60,409
Consolidated Funds | Level III | Equity securities: | Energy | Recent market information
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Total investments, at fair value	32,121
Consolidated Funds | Level III | Equity securities: | Energy | Other
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Total investments, at fair value	186,091		432,717
Consolidated Funds | Level III | Real estate-oriented investments: | Discounted cash flow
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Total investments, at fair value	$ 4,113,712		$ 3,276,236
Consolidated Funds | Level III | Real estate-oriented investments: | Discounted cash flow | Minimum
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Discount rate (as a percent)	6.00%		6.00%
Terminal capitalization rate (as a percent)	0.05		0.06
Direct capitalization rate (as a percent)	0.05		0.05
Net operating income growth rate (as a percent)	0.00%		0.00%
Absorption rate (as a percent)	21.00%		19.00%
Consolidated Funds | Level III | Real estate-oriented investments: | Discounted cash flow | Maximum
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Discount rate (as a percent)	44.00%		44.00%
Terminal capitalization rate (as a percent)	0.10		0.10
Direct capitalization rate (as a percent)	0.10		0.09
Net operating income growth rate (as a percent)	50.00%		37.00%
Absorption rate (as a percent)	50.00%		44.00%
Consolidated Funds | Level III | Real estate-oriented investments: | Discounted cash flow | Weighted Average
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Discount rate (as a percent)	12.00%		13.00%
Terminal capitalization rate (as a percent)	0.07		0.08
Direct capitalization rate (as a percent)	0.07		0.07
Net operating income growth rate (as a percent)	11.00%		10.00%
Absorption rate (as a percent)	37.00%		38.00%
Consolidated Funds | Level III | Real estate-oriented investments: | Market approach (comparable companies)
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Total investments, at fair value	$ 217,427		$ 262,218
Consolidated Funds | Level III | Real estate-oriented investments: | Market approach (comparable companies) | Minimum
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Earnings multiple	10		12
Consolidated Funds | Level III | Real estate-oriented investments: | Market approach (comparable companies) | Maximum
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Earnings multiple	13		18
Consolidated Funds | Level III | Real estate-oriented investments: | Market approach (comparable companies) | Weighted Average
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Earnings multiple	13		13
Consolidated Funds | Level III | Real estate-oriented investments: | Recent transaction price
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Total investments, at fair value	$ 578,071		$ 915,247
Consolidated Funds | Level III | Real estate-oriented investments: | Sales approach
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Total investments, at fair value	1,410,002		1,075,459
Consolidated Funds | Level III | Real estate-oriented investments: | Recent market information
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Total investments, at fair value	$ 2,383,897		$ 2,625,026
Consolidated Funds | Level III | Real estate-oriented investments: | Recent market information | Minimum
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Quoted prices / discount (as a percent)	0.00%		0.00%
Consolidated Funds | Level III | Real estate-oriented investments: | Recent market information | Maximum
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Quoted prices / discount (as a percent)	6.00%		6.00%
Consolidated Funds | Level III | Real estate-oriented investments: | Recent market information | Weighted Average
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Quoted prices / discount (as a percent)	4.00%		4.00%
Consolidated Funds | Level III | Real estate-oriented investments: | Market approach (value of underlying assets)
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Total investments, at fair value	$ 954,208		$ 766,755
Consolidated Funds | Level III | Real estate-oriented investments: | Market approach (value of underlying assets) | Minimum
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Underlying asset multiple	1		1
Consolidated Funds | Level III | Real estate-oriented investments: | Market approach (value of underlying assets) | Maximum
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Underlying asset multiple	1.8		1.5
Consolidated Funds | Level III | Real estate-oriented investments: | Market approach (value of underlying assets) | Weighted Average
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Underlying asset multiple	1.6		1.4
Consolidated Funds | Level III | Real estate-oriented investments: | Other
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Total investments, at fair value	$ 75,591		$ 49,799
Consolidated Funds | Level III | Real estate-oriented investments: | Discounted cash flow / Sales approach
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Total investments, at fair value	$ 106,006
Consolidated Funds | Level III | Real estate-oriented investments: | Discounted cash flow / Sales approach | Minimum
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Discount rate / Market transactions (as a percent)	6.00%
Consolidated Funds | Level III | Real estate-oriented investments: | Discounted cash flow / Sales approach | Maximum
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Discount rate / Market transactions (as a percent)	8.00%
Consolidated Funds | Level III | Real estate-oriented investments: | Discounted cash flow / Sales approach | Weighted Average
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Discount rate / Market transactions (as a percent)	7.00%
Consolidated Funds | Level III | Real estate-oriented investments: | Recent market information / Market approach (comparable companies)
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Total investments, at fair value	$ 96,816		$ 245,316
Consolidated Funds | Level III | Real estate-oriented investments: | Recent market information / Market approach (comparable companies) | Minimum
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Quoted prices discount earnings multiple			700.00%
Quoted prices / discount (as a percent)	1000.00%
Consolidated Funds | Level III | Real estate-oriented investments: | Recent market information / Market approach (comparable companies) | Maximum
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Quoted prices discount earnings multiple			900.00%
Quoted prices / discount (as a percent)	1200.00%
Consolidated Funds | Level III | Real estate-oriented investments: | Recent market information / Market approach (comparable companies) | Weighted Average
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Quoted prices discount earnings multiple			800.00%
Quoted prices / discount (as a percent)	1100.00%
Consolidated Funds | Level III | Real estate loan portfolios | Discounted cash flow
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Total investments, at fair value	$ 2,209,112		$ 2,019,261
Consolidated Funds | Level III | Real estate loan portfolios | Discounted cash flow | Minimum
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Discount rate (as a percent)	8.00%		8.00%
Consolidated Funds | Level III | Real estate loan portfolios | Discounted cash flow | Maximum
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Discount rate (as a percent)	20.00%		16.00%
Consolidated Funds | Level III | Real estate loan portfolios | Discounted cash flow | Weighted Average
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Discount rate (as a percent)	13.00%		13.00%
Consolidated Funds | Level III | Real estate loan portfolios | Recent transaction price
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Total investments, at fair value	$ 908,444		$ 379,844
Consolidated Funds | Level III | Other
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Total investments, at fair value	$ 4,730		$ 15,576