Equity Method Investment - Expense and Carrying Amount of Investment (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Equity Method Investments and Joint Ventures [Abstract]
Proportionate share of Kleo's net loss	$ 607	$ 1,993	$ 3,472	$ 4,308

Amount of income (loss) for proportionate share of equity method investee's income (loss).

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