Recently Issued Accounting Pronouncements - Summary of Impact of Adoption on Consolidated Statement of Operations (Detail) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended
Mar. 31, 2018	Mar. 31, 2017
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
License revenue	$ 45,867	$ 44,007
Service revenue	10,816	8,458
Cost of revenue-license	9,612	6,804
Marketing and selling	20,065	21,242
Benefit from income taxes	(2,465)	(101)
Net loss	$ (1,199)	$ (1,075)
Net loss-basic and diluted	$ (0.03)	$ (0.03)
Accounting Standards Update 2014-09 [Member] \| Calculated under Revenue Guidance in Effect before Topic 606 [Member]
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
License revenue	$ 43,568
Service revenue	10,618
Cost of revenue-license	7,451
Marketing and selling	20,519
Benefit from income taxes	(2,649)
Net loss	$ (1,805)
Net loss-basic and diluted	$ (0.05)
Accounting Standards Update 2014-09 [Member] \| Difference between Revenue Guidance in Effect before and after Topic 606 [Member]
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
License revenue	$ 2,299
Service revenue	198
Cost of revenue-license	2,161
Marketing and selling	(454)
Benefit from income taxes	184
Net loss	$ 606
Net loss-basic and diluted	$ 0.02

Cost of generating revenue from multiple-deliverable arrangements that include licensing fees and services revenue. Licensing revenue is consideration received from another party for the right to use, but not own, certain of the entity's intangible assets. Licensing arrangements include, but are not limited to, rights to use a patent, copyright, technology, manufacturing process, software or trademark. Licensing fees are generally, but not always, fixed as to amount and not dependent upon the revenue generated by the licensing party. An entity may receive licensing fees for licenses that also generate royalty payments to the entity. Services revenue may be derived by providing other, nonspecified, services during the reporting period.

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