FAIR VALUE - Summary of Valuation Techniques and Quantitative Information (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended		12 Months Ended
	Mar. 31, 2015 investment	Mar. 31, 2014 investment	Dec. 31, 2014	Feb. 28, 2014
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Total investments, at fair value	$ 48,734,371		46,533,799	$ 312,900
Number of investments that changed valuation technique	6
Credit-oriented investments:
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Number of investments that changed valuation technique	3	1
Equity securities:
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Number of investments that changed valuation technique	1	1
Real estate-oriented investments:
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Number of investments that changed valuation technique	1
Consolidated Funds
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Total investments, at fair value	48,734,371		46,533,799
Consolidated Funds | Level III
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Total investments, at fair value	28,015,703		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	214,234		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)	11.00%		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	475,228		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	120,690		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	88,309		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	436,108		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)	7.00%		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	140,392		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	97,659		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	244,440		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	0.9		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	1.1		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		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	187,152		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)	5.00%		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)	15.00%		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)	12.00%		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	13,358		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	4		3
Consolidated Funds | Level III | Credit-oriented investments: | Industrials | Market approach (comparable companies) | Maximum
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Earnings multiple	9		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	8		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	36,823		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	67,583		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	77,160		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	0.9		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	1.1		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	1		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	198,362		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)	10.00%		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)	14.00%		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: | Materials | Discounted cash flow
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Total investments, at fair value	138,398		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)	13.00%		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)	12.00%		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	257,288		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	9		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	16,459		64,490
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	219,701		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)	12.00%		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)	14.00%		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)	13.00%		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	547,453		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)	12.00%		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	162,887		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	7		7
Consolidated Funds | Level III | Credit-oriented investments: | Other | Market approach (comparable companies) | Maximum
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Earnings multiple	9		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	8		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	20,289		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	369,992		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	209,414
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 | Equity securities: | Financials | Recent transaction price
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Total investments, at fair value	266,438		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	148,477		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	759,272		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	1.2		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	1.1		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	124,776		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%		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%		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%		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	4,683
Consolidated Funds | Level III | Equity securities: | Industrials | Discounted cash flow | Minimum
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Discount rate (as a percent)	7.00%
Consolidated Funds | Level III | Equity securities: | Industrials | Discounted cash flow | Maximum
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Discount rate (as a percent)	9.00%
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)	8.00%
Consolidated Funds | Level III | Equity securities: | Industrials | Market approach (comparable companies)
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Total investments, at fair value	2,182,953		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	4		3
Consolidated Funds | Level III | Equity securities: | Industrials | Market approach (comparable companies) | Maximum
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Earnings multiple	15		15
Consolidated Funds | Level III | Equity securities: | Industrials | Market approach (comparable companies) | Weighted Average
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Earnings multiple	9		9
Consolidated Funds | Level III | Equity securities: | Industrials | Recent transaction price
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Total investments, at fair value	289,884		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	307,271		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	2,474,244		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	1		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	1,158,360		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	4		4
Consolidated Funds | Level III | Equity securities: | Materials | Market approach (comparable companies) | Maximum
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Earnings multiple	10		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	15,575		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	179,174		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	1,647,200		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	4		4
Consolidated Funds | Level III | Equity securities: | Other | Market approach (comparable companies) | Maximum
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Earnings multiple	11		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	336,896		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	150,220		151,933
Consolidated Funds | Level III | Equity securities: | Energy | Discounted cash flow
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Total investments, at fair value	39,577		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%		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%		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%		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	967,139		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	5		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	12		12
Consolidated Funds | Level III | Equity securities: | Energy | Recent transaction price
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Total investments, at fair value	62,459		60,409
Consolidated Funds | Level III | Equity securities: | Energy | Other
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Total investments, at fair value	422,931		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	3,566,031		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)	0.04		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)	60.00%		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)	13.00%		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)	12.00%		10.00%
Absorption rate (as a percent)	39.00%		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	227,085		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	12		12
Consolidated Funds | Level III | Real estate-oriented investments: | Market approach (comparable companies) | Maximum
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Earnings multiple	14		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	693,022		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	1,347,446		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	2,836,541		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)	3.00%		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	805,420		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	1.5		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	1.4		1.4
Consolidated Funds | Level III | Real estate-oriented investments: | Other
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Total investments, at fair value	52,395		49,799
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	201,027		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)	700.00%
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)	900.00%
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)	800.00%
Consolidated Funds | Level III | Real estate loan portfolios | Discounted cash flow
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Total investments, at fair value	1,980,758		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)	10.00%		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)	15.00%		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)	12.00%		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	425,494		379,844
Consolidated Funds | Level III | Other
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Total investments, at fair value	$ 3,576		15,576