Equity Method Investments - Summarized unaudited financial data (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Sep. 30, 2020	Dec. 31, 2019
Summary financial information of equity method investments
Current assets	$ 188,968	$ 61,690	$ 145,740
Non-current assets		24,272
Current liabilities	42,657	53,523	34,187
Non-current liabilities		27,939
Net revenues	151,184	50,354	149,387
Operating loss	41,700	(28,510)	49,243
Net loss	$ (2,138)	$ (52,006)	$ (3,471)