Stock-Based Compensation Expense and Its Net Impact on Basic and Diluted Earnings Per Share (Detail) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Employee Service Share-Based Compensation, Allocation of Recognized Period Costs [Line Items]
Stock-based compensation expense before taxes	$ 23,800	$ 15,269
Related income tax benefits	(11,076)	(11,304)
Stock-based compensation expense, net of taxes	$ 12,724	$ 3,965
Basic earnings per share	$ (0.15)	$ (0.05)
Diluted earnings per share	$ (0.15)	$ (0.05)
Maintenance and Service
Employee Service Share-Based Compensation, Allocation of Recognized Period Costs [Line Items]
Allocated Share-based Compensation Expense	$ 1,228	$ 1,010
Selling, General and Administrative
Employee Service Share-Based Compensation, Allocation of Recognized Period Costs [Line Items]
Allocated Share-based Compensation Expense	13,131	8,278
Research and Development
Employee Service Share-Based Compensation, Allocation of Recognized Period Costs [Line Items]
Allocated Share-based Compensation Expense	$ 9,441	$ 5,981

Reduction in Basic Earnings per Share Impact of Stock Based Compensation

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Reduction in Diluted Earnings per Share Impact of Stock Based Compensation

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- Definition

Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

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The amount of expense, net of income tax, recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

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The total recognized tax benefit related to compensation cost for equity-based payment arrangements recognized in income during the period.

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The aggregate amount of noncash, equity-based employee remuneration. This may include the value of stock or unit options, amortization of restricted stock or units, and adjustment for officers' compensation. As noncash, this element is an add back when calculating net cash generated by operating activities using the indirect method.

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