Segment Information - Summary of Long-Lived Assets by Geographical Area (Detail) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Segment Reporting, Asset Reconciling Item [Line Items]
Long-lived assets, net of accumulated depreciation	$ 5,444	$ 4,390
U.S.
Segment Reporting, Asset Reconciling Item [Line Items]
Long-lived assets, net of accumulated depreciation	5,406	4,342
Global
Segment Reporting, Asset Reconciling Item [Line Items]
Long-lived assets, net of accumulated depreciation	$ 38	$ 48