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Common Stock and Warrants - Summary of Warrants Accounted for as Liabilities and Recorded as Derivative Financial Instruments (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Fair Value Disclosures [Abstract]
Fair value of warrants at beginning of year	$ 5	$ 13,769
Exercise of warrants		(35)
Foreign exchange (gains) losses	(1)	384
Change in fair value of warrants during the year	$ (4)	(14,113)
Fair value of warrants at end of year		$ 5

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Fair value of warrants liability.

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Fair value of warrants liability exercise.

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Amount of expense (income) related to adjustment to fair value of warrant liability.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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Amount before tax of foreign currency transaction realized and unrealized gain (loss) recognized in the income statement.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
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