Segment Information - Schedule of Segment Reporting Information (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Segment Reporting Information [Line Items]
Revenue	$ 106,456	$ 100,406	$ 336,480	$ 335,038
Adjusted EBITDA	8,175	(2,335)	35,596	26,814
Software [Member]
Segment Reporting Information [Line Items]
Revenue	93,980	85,772	296,634	291,150
Adjusted EBITDA	7,071	(2,834)	32,637	26,415
CES [Member]
Segment Reporting Information [Line Items]
Revenue	10,868	12,803	34,386	37,265
Adjusted EBITDA	1,607	1,707	4,086	4,280
All Other [Member]
Segment Reporting Information [Line Items]
Revenue	1,608	1,831	5,460	6,623
Adjusted EBITDA	$ (503)	$ (1,208)	$ (1,127)	$ (3,881)