Segment Information - Long-Lived Assets by Geographic Area (Detail) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Revenues from External Customers and Long-Lived Assets [Line Items]
Long-lived assets, Total	$ 113,631	$ 106,720
United States [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Long-lived assets, Total	109,443	102,572
International [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Long-lived assets, Total	$ 4,188	$ 4,148