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Equity Incentive Plan (Tables)

12 Months Ended

Dec. 31, 2020

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, 2018			17,387
Restricted stock units granted			(1,622	)
Restricted stock units forfeited			22
Available for grant at December 31, 2018			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

Summary of Restricted Stock Units and Changes

Restricted Stock Units

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, 2018			1,538				10.36				0.33
Restricted stock units granted			1,622				13.86
Restricted stock units vested			(1,517	)			9.79
Restricted stock units forfeited			(22	)			11.75
Non-vested at December 31, 2018			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

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, 2018, 2019 and 2020.

		Year Ended December 31
		2018				2019				2020
		US$				US$				US$
Cost of sales			390				305				253
Research and development			13,278				9,927				10,132
Sales and marketing			3,407				1,789				1,759
General and administrative			3,704				2,570				2,445
			20,779				14,591				14,589

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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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-Publisher FASB
-Name Accounting Standards Codification
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Tabular disclosure of the changes in outstanding nonvested shares.

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