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Equity Incentive Plan (Tables)

12 Months Ended

Dec. 31, 2021

Share-based Payment Arrangement [Abstract]

Summary of Stock Option and Restricted Stock Units Activity

The following is a summary of, the 2015 Plan, which includes restricted stock units:

		Unit (in Thousands)
Available for grant at January 1, 2019			15,787
Restricted stock units granted			(1,584	)
Restricted stock units forfeited			57
Available for grant at December 31, 2019			14,260
Restricted stock units granted			(1,692	)
Restricted stock units forfeited			57
Available for grant at December 31, 2020			12,625
Restricted stock units granted			(2,326	)
Restricted stock units forfeited			134
Available for grant at December 31, 2021			10,433

Summary of Restricted Stock Units and Changes

A summary of the status of restricted stock units and changes is as follows:

		Number of Non-vested Stock Units (in Thousands)				Weighted Average Grant Date Fair Value (US$)				Weight Average Remaining Recognition Period (Years)
Non-vested at January 1, 2019			1,621				13.85				0.38
Restricted stock units granted			1,584				8.01
Restricted stock units vested			(1,505	)			14.12
Restricted stock units forfeited			(57	)			9.59
Non-vested at December 31, 2019			1,643				8.08				0.29
Restricted stock units granted			1,692				9.40
Restricted stock units vested			(1,564	)			8.02
Restricted stock units forfeited			(57	)			9.31
Non-vested at December 31, 2020			1,714				9.37				0.31
Restricted stock units granted			2,326				17.62
Restricted stock units vested			(1,596	)			9.31
Restricted stock units forfeited			(134	)			14.99
Non-vested at December 31, 2021			2,310				17.37				1.57

Stock-based Compensation Expense

The following table shows total stock-based compensation expense included in the Consolidated Statements of Income for the years ended December 31, 2019, 2020 and 2021.

		Year Ended December 31
		2019				2020				2021
		US$				US$				US$
Cost of sales			305				253				389
Research and development			9,927				10,132				12,864
Sales and marketing			1,789				1,759				2,366
General and administrative			2,570				2,445				3,926
			14,591				14,589				19,545

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Tabular disclosure of allocation of amount expensed and capitalized for award under share-based payment arrangement to statement of income or comprehensive income and statement of financial position. Includes, but is not limited to, corresponding line item in financial statement.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
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Tabular disclosure of the changes in outstanding nonvested shares.

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-Publisher FASB
-Name Accounting Standards Codification
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