Deferred Revenue and Advance Payments (Detail) - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016
Deferred Revenue Disclosure [Abstract]
Deferred product licenses revenue, Current	$ 10,513	$ 13,023
Deferred subscription services revenue, Current	17,741	18,303
Deferred product support revenue, Current	156,804	162,781
Deferred other services revenue, Current	8,681	10,015
Gross current deferred revenue and advance payments	193,739	204,122
Less: unpaid deferred revenue, Current	(70,657)	(98,587)
Net current deferred revenue and advance payments	123,082	105,535
Deferred product licenses revenue, Non-current	7,087	9,118
Deferred subscription services revenue, Non-current	784	1,307
Deferred product support revenue, Non-current	7,211	5,751
Deferred other services revenue, Non-current	856	690
Gross non-current deferred revenue and advance payments	15,938	16,866
Less: unpaid deferred revenue, Non-current	(5,241)	(2,951)
Net non-current deferred revenue and advance payments	$ 10,697	$ 13,915