Investments of Operating Entities and Consolidated Funds - Lehman Claims (Details) (USD $)											1 Months Ended							3 Months Ended						1 Months Ended
	Sep. 30, 2014	Dec. 31, 2013	Sep. 30, 2014 Lehman claims, at fair value	Apr. 30, 2014 Lehman claims, at fair value	Dec. 31, 2013 Lehman claims, at fair value	Nov. 30, 2013 Lehman claims, at fair value	Jun. 30, 2013 Lehman claims, at fair value	Nov. 30, 2012 Lehman claims, at fair value	Nov. 02, 2012 Lehman claims, at fair value	Sep. 15, 2008 Lehman claims, at fair value	Jul. 31, 2014 Enterprise Master Lehman claims, at fair value	Jun. 30, 2014 Enterprise Master Lehman claims, at fair value	Sep. 26, 2013 Enterprise Master Lehman claims, at fair value	Feb. 29, 2012 Enterprise Master Lehman claims, at fair value	Dec. 31, 2011 Enterprise Master Lehman claims, at fair value	Jul. 31, 2010 Enterprise Master Lehman claims, at fair value	Jun. 30, 2010 Enterprise Master Lehman claims, at fair value	Sep. 30, 2014 Enterprise Master Lehman claims, at fair value	Jan. 30, 2014 Enterprise Master Lehman claims, at fair value	Feb. 28, 2013 Enterprise Master Lehman claims, at fair value	Nov. 30, 2012 Enterprise Master Lehman claims, at fair value	Nov. 02, 2012 Enterprise Master Lehman claims, at fair value	Sep. 15, 2008 Enterprise Master Lehman claims, at fair value	Sep. 30, 2014 Enterprise Master Cash	Jul. 31, 2013 Enterprise Master Cash	Sep. 30, 2014 Enterprise LP Lehman claims, at fair value
Investment Holdings [Line Items]
Initial value										$ 1,000,000													$ 24,300,000	$ 4,900,000	$ 4,900,000
Unsecured claim									900,000													1,300,000
Percent of client's Best Claim																		101.50%
Distribution percent withheld for tax													30.00%						30.00%
Value of Best Claim																		200,000
Dividend percent received				7.80%		23.70%	43.30%	25.20%													25.20%
Dividend amount received				100,000		200,000	400,000	200,000													300,000
Total Dividend Amount Received			1,000,000
Total Dividend percent received			100.00%
Other Investments, Claim Settlement Sold																				1,300,000
Assets returned															2,400,000		9,500,000
Proceeds from sale of returned assets																10,700,000
Distributions of proceeds from returned assets											5,700,000	800,000	14,900,000	2,900,000										0
Tax Withholding on Distribution of Proceeds from Sale of Returned Assets													1,000,000					1,000,000
Other investments	130,584,000	99,483,000	360,000		378,000
Other Investments, claim to trust assets held by LBIE through Lehman Brothers																		10,600,000
Percentage of securities liquidated at LBI																		90.00%
Distributions of client's Best Claim													100.00%						6.00%
Other Investments, initial claim current value																		$ 500,000								$ 400,000
Recoverable claims assigned to variable interest entities																		100.00%
Percentage of Net Equity Claim			138.30%		131.50%