Equity Method Investment - Roll-forward of Carrying Value (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Carrying value of equity method investment
Beginning balance			$ 5,338	$ 11,414
Loss recognized in connection with equity method investment	$ (607)	$ (1,993)	(3,472)	(4,308)
Ending balance	$ 1,866	$ 7,106	$ 1,866	$ 7,106

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

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