Revenue from Contracts with Customers - Schedule of Disaggregation of Revenue (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Disaggregation Of Revenue [Line Items]
Total revenue	$ 119,912	$ 98,561	$ 270,075	$ 230,024
Term Licenses [Member]
Disaggregation Of Revenue [Line Items]
Total revenue	57,624	43,260	142,558	112,641
Perpetual Licenses [Member]
Disaggregation Of Revenue [Line Items]
Total revenue	9,008	7,758	20,469	15,920
Maintenance [Member]
Disaggregation Of Revenue [Line Items]
Total revenue	30,549	28,885	60,243	57,093
Professional Software Services [Member]
Disaggregation Of Revenue [Line Items]
Total revenue	2,377	1,930	5,829	4,622
Software Related Services [Member]
Disaggregation Of Revenue [Line Items]
Total revenue	7,481	5,444	15,579	12,378
Client Engineering Services [Member]
Disaggregation Of Revenue [Line Items]
Total revenue	10,268	9,640	20,945	23,518
Other [Member]
Disaggregation Of Revenue [Line Items]
Total revenue	$ 2,605	$ 1,644	$ 4,452	$ 3,852