Investments - Additional Information (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended				3 Months Ended		9 Months Ended			3 Months Ended		9 Months Ended			3 Months Ended	9 Months Ended				9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012	Dec. 31, 2012	Sep. 30, 2013 EMP III [Member] Variable Interest Entity, Primary Beneficiary [Member]	Sep. 30, 2013 G5 [Member]	Sep. 30, 2012 G5 [Member]	Sep. 30, 2013 G5 [Member]	Sep. 30, 2012 G5 [Member]	Dec. 31, 2012 G5 [Member]	Sep. 30, 2013 ABS [Member]	Sep. 30, 2012 ABS [Member]	Sep. 30, 2013 ABS [Member]	Sep. 30, 2012 ABS [Member]	Dec. 31, 2012 ABS [Member]	Sep. 30, 2012 Pan [Member]	Sep. 30, 2013 Pan [Member]	Sep. 30, 2012 Pan [Member]	Dec. 31, 2012 Pan [Member]	Dec. 31, 2008 Pan [Member]	Sep. 30, 2013 Pan [Member] Variable Interest Entity, Primary Beneficiary [Member]	Sep. 30, 2013 Trilantic [Member]	Dec. 31, 2012 Trilantic [Member]	Jun. 30, 2013 EMCP III [Member]	Sep. 30, 2013 EMCP III [Member] EMP III [Member]	Jun. 30, 2013 EMCP III [Member] EMP III [Member]	Sep. 30, 2013 EMCP III [Member] Parent [Member]	Jun. 30, 2013 EMCP III [Member] Parent [Member]	Jun. 30, 2013 EMCP III [Member] Noncontrolling Interest [Member]	Sep. 25, 2013 Trilantic V [Member]
Schedule of Investments [Line Items]
Assets	$ 1,103,341	$ 1,028,764	$ 1,103,341	$ 1,028,764	$ 1,145,218	$ 3,882
Liabilities	549,880		549,880		604,742	35
Subscribed capital commitments																									201,000
Capital commitment																											10,750		1,000	9,750
Unfunded commitments for capital contributions	10,224		10,224																							3,642		639
Equity method investment	62,223		62,223		69,320		17,991		17,991		19,720	44,232		44,232		46,851		0		2,749	4,158										1,038
Net realized and unrealized gains (losses) on private equity fund investments, including performance fees	2,663	423	5,213	(185)
Previously received carried interest subject to repayment	2,701		2,701
Investments Disclosure																							14,479	14,999
Equity method investment (as a percent)							49.00%		49.00%			45.00%		45.00%				68.00%		50.00%
Income from Equity Method Investments	562	415	2,333	3,519			(226)	(300)	(42)	970		788	796	2,430	2,418		(81)	(55)	131
Goodwill, Gross																						3,020
Intangible assets, Gross																						1,440
Intangible assets, useful life																						7 years
Asset Impairment Charges	2,718
Disposal Group, Including Discontinued Operation, Revenue	651		91
Disposal Group, Including Discontinued Operation, Operating Income (Loss)	(93)		(1,518)
Assets Held for Sale	3,339		3,339		0
Goodwill	188,006		188,006		188,684													1,185
Finite-Lived Intangible Assets, Net																		1,414
Liabilities Held for Sale	584		584		0
Accrued Compensation and Benefits	110,255		110,255		138,187													126
Accounts Payable and Accrued Expenses	18,648		18,648		17,909													412
Amortization of intangible assets	$ 647	$ 649	$ 1,941	$ 2,045