CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (USD $) In Thousands, unless otherwise specified	6 Months Ended
	Jun. 30, 2013	Jun. 30, 2012
Cash Flows from Operating Activities:
Net cash used in operating activities	$ (11,540)	$ (9,624)
Cash Flows from Investing Activities:
Proceeds from sales of and distributions from companies and funds	1,403	11,061
Advances and loans to companies	(8,100)	(5,141)
Origination fees on mezzanine loans	42	46
Acquisitions of ownership interests in companies and funds	(15,131)	(16,190)
Increase in marketable securities	(29,913)	(141,997)
Decrease in marketable securities	92,552	133,751
Repayment of advances and loans to companies	928	3,144
Capital expenditures	(21)	(25)
Proceeds from sale of discontinued operations, net	6,434
Net cash provided by (used in) investing activities	48,194	(15,351)
Cash Flows from Financing Activities:
Repurchase of convertible senior debentures	(43)
Issuance of Company common stock, net	92	513
Net cash provided by financing activities	49	513
Net Increase (Decrease) in Cash and Cash Equivalents	36,703	(24,462)
Cash and Cash Equivalents at beginning of period	66,029	83,187
Cash and Cash Equivalents at end of period	$ 102,732	$ 58,725