Deferred Revenue and Advance Payments (Detail) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Deferred Revenue Disclosure [Abstract]
Deferred product licenses revenue, Current	$ 13,023	$ 13,506
Deferred subscription services revenue, Current	18,303	15,763
Deferred product support revenue, Current	162,781	158,738
Deferred other services revenue, Current	10,015	9,149
Gross current deferred revenue and advance payments	204,122	197,156
Less: unpaid deferred revenue, Current	(98,587)	(96,461)
Net current deferred revenue and advance payments	105,535	100,695
Deferred product licenses revenue, Non-current	9,118	5,397
Deferred subscription services revenue, Non-current	1,307	2,138
Deferred product support revenue, Non-current	5,751	7,607
Deferred other services revenue, Non-current	690	795
Gross non-current deferred revenue and advance payments	16,866	15,937
Less: unpaid deferred revenue, Non-current	(2,951)	(6,942)
Net non-current deferred revenue and advance payments	$ 13,915	$ 8,995