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	6 Months Ended
Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Employee Service Share-Based Compensation, Allocation of Recognized Period Costs [Line Items]
Stock-based compensation expense before taxes	$ 8,534	$ 9,030	$ 15,612	$ 16,861
Related income tax benefits	(2,892)	(2,911)	(4,935)	(5,729)
Stock-based compensation expense, net of taxes	$ 5,642	$ 6,119	$ 10,677	$ 11,132
Basic earnings per share	$ (0.06)	$ (0.07)	$ (0.12)	$ (0.12)
Diluted earnings per share	$ (0.06)	$ (0.07)	$ (0.12)	$ (0.12)
Software Licenses
Employee Service Share-Based Compensation, Allocation of Recognized Period Costs [Line Items]
Stock-based compensation expense before taxes	$ 182	$ 182	$ 337	$ 375
Maintenance and Service
Employee Service Share-Based Compensation, Allocation of Recognized Period Costs [Line Items]
Stock-based compensation expense before taxes	416	486	783	902
Selling, General and Administrative
Employee Service Share-Based Compensation, Allocation of Recognized Period Costs [Line Items]
Stock-based compensation expense before taxes	3,944	4,722	6,868	8,789
Research and Development
Employee Service Share-Based Compensation, Allocation of Recognized Period Costs [Line Items]
Stock-based compensation expense before taxes	$ 3,992	$ 3,640	$ 7,624	$ 6,795

Reduction in Basic Earnings per Share Impact of Stock Based Compensation

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- Definition

Reduction in Diluted Earnings per Share Impact of Stock Based Compensation

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- Definition

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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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (h)(1)(i)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3602-108585

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