Ownership Interests in and Advances to Partner Companies and Funds - Results of Operations for Equity Method Investments (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Equity Method Investments and Joint Ventures [Abstract]
Revenue	$ 401,182	$ 319,197	$ 270,666
Gross profit	113,801	97,405	121,297
Net loss	$ (140,801)	$ (108,994)	$ (63,452)