Prepaid and other current assets - Schedule of prepaid and other current assets consisted of the following (Details) - USD ($) $ in Thousands	Jun. 30, 2021	Dec. 31, 2020
Prepaid Expense And Other Assets Current [Abstract]
Insurance	$ 540	$ 2,568
Paragraph IV legal proceeding costs	2,660
Other	3,978	4,975
Prepaid and other current assets	$ 7,178	$ 7,543

Amount of asset related to consideration paid in advance for insurance that provides economic benefits within a future period of one year or the normal operating cycle, if longer.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 340
-SubTopic 10
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-Name Accounting Standards Codification
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-Publisher FASB
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Name:	us-gaap_PrepaidInsurance
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant