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Long-Term Investments (Tables)

12 Months Ended

Dec. 31, 2020

Investments, Debt and Equity Securities [Abstract]

Long-Term Investments

As of December 31, 2019 and 2020, the Company held equity investments in several privately-held companies with the carrying value as follows:

		Percentage of Ownership								December 31
		2019				2020				2019				2020
										US$				US$
Equity securities measured at cost:
Cashido Corp. (Cashido)			0.6	%			0.6	%			—				—
Vastview Technology, Corp. (Vastview)			2.9	%			2.9	%			—				—
Deep Vision, Inc (Deep Vision)			16.2	%			16.2	%			3,000				5,000
											3,000				5,000

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