Geographic Information - Schedule of Geographic Information (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Segment Reporting Information [Line Items]
Total revenue	$ 34,024	$ 30,527	$ 65,922	$ 57,105
UNITED STATES
Segment Reporting Information [Line Items]
Total revenue	29,227	26,115	55,686	48,611
CANADA
Segment Reporting Information [Line Items]
Total revenue	2,989	2,603	6,740	5,592
Non-US [Member]
Segment Reporting Information [Line Items]
Total revenue	$ 1,808	$ 1,809	$ 3,496	$ 2,902