Deferred Revenue and Advance Payments (Detail) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Deferred Revenue Disclosure [Abstract]
Deferred product licenses revenue, Current	$ 131	$ 481
Deferred subscription services revenue, Current	16,567	16,561
Deferred product support revenue, Current	161,135	161,670
Deferred other services revenue, Current	7,058	8,395
Total current deferred revenue and advance payments	184,891	187,107
Deferred product licenses revenue, Non-current	262	293
Deferred subscription services revenue, Non-current	84	97
Deferred product support revenue, Non-current	2,789	3,417
Deferred other services revenue, Non-current	525	537
Total non-current deferred revenue and advance payments	$ 3,660	$ 4,344