Income Taxes - Operating Loss Carryforwards (Details) $ in Thousands	12 Months Ended
Dec. 31, 2020 USD ($)
Federal
Operating Loss Carryforwards
Operating loss carryforward	$ 160,531
Research tax credits	3,770
State
Operating Loss Carryforwards
Operating loss carryforward	141,751
Research tax credits	645
Foreign
Operating Loss Carryforwards
Indefinite federal net operating loss carryforward	$ 79,223

Amount of operating loss carryforward, before tax effects, available to reduce future taxable income under enacted tax laws.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32559-109319

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant