Ownership Interests in and Advances to Partner Companies and Funds - Schedule of Results of Operations (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Investments in and Advances to Affiliates [Abstract]
Revenue	$ 39,461	$ 88,234	$ 83,329	$ 198,627
Gross profit	22,084	56,257	46,673	134,328
Net loss	$ (35,468)	$ (54,572)	$ (69,084)	$ (86,377)

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

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