Segment Information - Total Revenue to Unaffiliated Customers by Geographic Area, Based on Location of Customer (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues	$ 47,926	$ 47,582	$ 94,579	$ 89,418
North America [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues	26,039	25,708	51,038	47,521
Europe [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues	8,427	8,167	16,888	14,636
Japan [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues	5,554	5,146	11,656	11,334
Asia Pacific [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues	7,714	8,091	14,584	15,363
Other [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues	$ 192	$ 470	$ 413	$ 564