Ownership Interests in and Advances to Partner Companies and Funds - Schedule of Results of Operations (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Investments in and Advances to Affiliates [Abstract]
Revenue	$ 43,868	$ 110,393
Gross profit	24,589	78,071
Net loss	$ (33,616)	$ (31,805)

The amount of net income (loss) reported by an equity method investment of the entity.

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