Other Income (Expense), Net (Details) - USD ($)	3 Months Ended
Mar. 31, 2021	Mar. 31, 2020
Other Income (Expense), Net
Income from government grants	$ 100,000	$ 1,400,000
Foreign currency exchange loss	$ 173,000	$ 43,000

Amount before tax of foreign currency transaction realized and unrealized gain (loss) recognized in the income statement.

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