Equity Method Investment - Expense and Carrying Amount of Investment (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Equity Method Investments and Joint Ventures [Abstract]
Proportionate share of Kleo's net loss	$ 1,485	$ 1,415	$ 2,865	$ 2,315

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

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