Equity Method Investment - Roll forward of Carrying Value (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Carrying value of equity method investment
Beginning balance	$ 5,338	$ 11,414
Loss recognized in connection with equity method investment	(1,380)	(900)
Ending balance	$ 3,958	$ 10,514

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

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration