Ownership Interests in and Advances to Partner Companies and Funds - Results of Operations for Equity Method Investments (Details) - High Traction Stage [Member] - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Schedule of Equity Method Investments [Line Items]
Revenue	$ 145,632	$ 283,009
Gross profit	78,465	181,571
Net loss	$ (127,007)	$ (154,696)

The amount of gross profit (loss) reported by an equity method investment of the entity.

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

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Amount of revenue from sale of product and rendering of service reported by equity method investee.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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