Segment Information - Schedule of Segment Reporting Information (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Segment Reporting Information [Line Items]
Revenue	$ 106,773	$ 93,360	$ 234,632	$ 206,617
Adjusted EBITDA	5,165	5,303	29,149	34,853
Software [Member]
Segment Reporting Information [Line Items]
Revenue	92,315	79,314	205,378	178,456
Adjusted EBITDA	5,207	4,718	29,249	33,746
CES [Member]
Segment Reporting Information [Line Items]
Revenue	12,412	12,417	24,462	24,497
Adjusted EBITDA	1,467	1,508	2,573	2,564
All Other [Member]
Segment Reporting Information [Line Items]
Revenue	2,046	1,629	4,792	3,664
Adjusted EBITDA	$ (1,509)	$ (923)	$ (2,673)	$ (1,457)