Restatement and Revision of Quarterly Condensed Consolidated Financial Statements - Consolidated Statements of Comprehensive Loss Adjustments (Details) - USD ($) $ in Thousands	3 Months Ended								6 Months Ended	9 Months Ended			12 Months Ended
	Dec. 31, 2020	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Jun. 30, 2020	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2018	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Error corrections and prior period adjustments restatement
Net income (loss)	$ (12,055)	$ (12,737)	$ (9,140)	$ (6,539)	$ (6,876)	$ (15,532)	$ (36,980)	$ (26,576)	$ (15,679)	$ (28,416)	$ (79,088)	$ (155,939)	$ (40,471)	$ (85,964)	$ (157,957)
Total comprehensive loss		(12,817)	(9,004)	(6,635)		(17,611)			(15,639)	(28,456)	(81,257)		(40,460)	(75,765)	$ (163,151)
As originally reported
Error corrections and prior period adjustments restatement
Net income (loss)		(12,779)	(10,781)	(7,983)		(17,331)			(18,764)	(31,543)	(80,887)		(43,609)	(90,419)
Total comprehensive loss		(12,859)	(10,645)	(8,079)		(19,410)			(18,724)	(31,583)	(83,056)		(43,598)	(80,220)
Adjustments
Error corrections and prior period adjustments restatement
Net income (loss)		42	1,641	1,444		1,799			3,085	3,127	1,799		3,138	4,455
Total comprehensive loss		$ 42	$ 1,641	$ 1,444		$ 1,799			$ 3,085	$ 3,127	$ 1,799		$ 3,138	$ 4,455