Revenues - Schedule of Revenues on Disaggregated Basis (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Disaggregation Of Revenue [Line Items]
Revenues	$ 10,854	$ 6,945	$ 19,286	$ 12,408
Wireless [Member]
Disaggregation Of Revenue [Line Items]
Revenues	10,637	6,506	18,809	11,322
Wireless [Member] | CommSuite & Netwise [Member]
Disaggregation Of Revenue [Line Items]
Revenues	5,293	4,884	9,947	8,763
Wireless [Member] | SafePath [Member]
Disaggregation Of Revenue [Line Items]
Revenues	3,775	755	5,908	1,079
Wireless [Member] | ViewSpot [Member]
Disaggregation Of Revenue [Line Items]
Revenues	735		1,521
Wireless [Member] | Consulting Services and Other [Member]
Disaggregation Of Revenue [Line Items]
Revenues	821	594	1,408	1,197
Wireless [Member] | Legacy Software Licenses [Member]
Disaggregation Of Revenue [Line Items]
Revenues	13	273	25	283
Graphics [Member]
Disaggregation Of Revenue [Line Items]
Revenues	217	439	477	1,086
Graphics [Member] | Software [Member]
Disaggregation Of Revenue [Line Items]
Revenues	$ 217	$ 439	$ 477	$ 1,086