Payment Obligation in Connection with Hirsch Acquisition (Detail) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Related Party Transaction [Line Items]
2019 (remaining three months)	$ 12,096
2020	1,671
Total	13,767
Less: Current portion - payment obligation	(1,192)	$ (1,025)
Long-term payment obligation	860	$ 1,860
Hirsch Electronics
Related Party Transaction [Line Items]
2019 (remaining three months)	319
2020	1,408
2021	363
Present value discount factor	(38)
Total	2,052
Less: Current portion - payment obligation	(1,192)
Long-term payment obligation	$ 860