Revenue - Financial Statement Effect of Applying ASC 606 (Income Statement) (Detail) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Revenues
Software as a service and platform as a service	$ 104,280	$ 99,447
License	28,046	59,381
Maintenance	56,659	54,471
Services	20,325	18,163
Operating expenses
Selling and marketing	31,893	27,137
Other income (expense)
Interest income	2,744	106
Other, net	(55)	649
Income tax provision
Income tax benefit	(3,952)	$ (4,174)
Calculated under Revenue Guidance in Effect before Topic 606 [Member]
Revenues
Software as a service and platform as a service	105,174
License	43,921
Maintenance	55,771
Services	20,029
Operating expenses
Selling and marketing	30,346
Other income (expense)
Interest income	179
Other, net	(784)
Income tax provision
Income tax benefit	(2,043)
Difference between Revenue Guidance in Effect before and after Topic 606 [Member] | Accounting Standards Update 2014-09 [Member]
Revenues
Software as a service and platform as a service	(894)
License	(15,875)
Maintenance	888
Services	296
Operating expenses
Selling and marketing	1,547
Other income (expense)
Interest income	2,565
Other, net	729
Income tax provision
Income tax benefit	$ (1,909)