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Stock Based Compensation (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Stock-based compensation	$ 44,906	$ 37,897	$ 33,577
Income tax benefit	(13,060)	(8,360)	(12,036)
Total stock-based compensation expense after income taxes	31,846	29,537	21,541
Cost Of Revenues
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Stock-based compensation	4,227	3,480	3,129
Engineering And Development
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Stock-based compensation	12,039	9,913	9,181
Selling and Administrative
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Stock-based compensation	$ 28,640	$ 24,504	$ 21,267

X

- Definition

Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

+ References

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