CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (USD $) In Thousands, unless otherwise specified	9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012
Cash Flows from Operating Activities:
Net cash used in operating activities	$ (16,299)	$ (12,616)
Cash Flows from Investing Activities:
Proceeds from sales of and distributions from companies and funds	2,603	14,526
Advances and loans to companies	(9,350)	(13,315)
Origination fees on mezzanine loans	42	74
Acquisitions of ownership interests in companies and funds	(28,718)	(21,719)
Increase in marketable securities	(47,072)	(209,876)
Decrease in marketable securities	129,664	226,133
Repayment of advances and loans to companies	1,044	3,214
Capital expenditures	(37)	(25)
Proceeds from sale of discontinued operations, net	6,434	0
Net cash provided by (used in) investing activities	54,610	(988)
Cash Flows from Financing Activities:
Repurchase of convertible senior debentures	(43)	0
Issuance of Company common stock, net	4,397	1,568
Net cash provided by financing activities	4,354	1,568
Net Increase (Decrease) in Cash and Cash Equivalents	42,665	(12,036)
Cash and Cash Equivalents at beginning of period	66,029	83,187
Cash and Cash Equivalents at end of period	$ 108,694	$ 71,151