Recent Accounting Pronouncements - Summary of Impact of Adoption on Consolidated Statement of Operations (Detail) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
License revenue	$ 60,687	$ 57,801	$ 117,370	$ 110,266
Cost of revenue-license	10,816	11,022	24,116	20,678
Marketing and selling	20,081	22,722	40,170	43,964
(Benefit) provision for income taxes	1,274	(1,027)	(1,191)	(1,128)
Net income (loss)	$ 695	$ (496)	$ (504)	$ (1,571)
Net income (loss)-basic and diluted	$ 0.02	$ (0.01)	$ (0.01)	$ (0.04)
License [Member]
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
License revenue	$ 48,093	$ 47,447	$ 93,960	$ 91,454
Cost of revenue-license	7,282	7,159	16,894	13,963
Service [Member]
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
License revenue	12,594	10,354	23,410	18,812
Cost of revenue-license	2,674	$ 2,982	5,498	$ 4,956
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]
Marketing and selling	20,807		41,350
(Benefit) provision for income taxes	154		(2,495)
Net income (loss)	$ (2,999)		$ (4,804)
Net income (loss)-basic and diluted	$ (0.07)		$ (0.12)
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]
Marketing and selling	$ (726)		$ (1,180)
(Benefit) provision for income taxes	1,120		1,304
Net income (loss)	$ 3,694		$ 4,300
Net income (loss)-basic and diluted	$ 0.09		$ 0.11
Accounting Standards Update 2014-09 [Member] \| License [Member] \| Calculated under Revenue Guidance in Effect before Topic 606 [Member]
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
License revenue	$ 44,005		$ 87,573
Cost of revenue-license			14,733
Accounting Standards Update 2014-09 [Member] \| License [Member] \| Difference between Revenue Guidance in Effect before and after Topic 606 [Member]
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
License revenue	$ 4,088		6,387
Cost of revenue-license			2,161
Accounting Standards Update 2014-09 [Member] \| Service [Member] \| Calculated under Revenue Guidance in Effect before Topic 606 [Member]
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
License revenue			23,212
Accounting Standards Update 2014-09 [Member] \| Service [Member] \| Difference between Revenue Guidance in Effect before and after Topic 606 [Member]
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
License revenue			$ 198

The aggregate costs related to goods produced and sold and services rendered by an entity during the reporting period. This excludes costs incurred during the reporting period related to financial services rendered and other revenue generating activities.

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