Revenues - Schedule of Revenues on Disaggregated Basis (Detail) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Disaggregation Of Revenue [Line Items]
Revenues	$ 8,432	$ 5,463
Wireless [Member]
Disaggregation Of Revenue [Line Items]
Revenues	8,172	4,816
Wireless [Member] | CommSuite & Netwise [Member]
Disaggregation Of Revenue [Line Items]
Revenues	4,678	3,974
Wireless [Member] | SafePath [Member]
Disaggregation Of Revenue [Line Items]
Revenues	2,134	323
Wireless [Member] | ViewSpot [Member]
Disaggregation Of Revenue [Line Items]
Revenues	786
Wireless [Member] | Consulting Services and Other [Member]
Disaggregation Of Revenue [Line Items]
Revenues	561	509
Wireless [Member] | Legacy Software Licenses [Member]
Disaggregation Of Revenue [Line Items]
Revenues	13	10
Graphics [Member]
Disaggregation Of Revenue [Line Items]
Revenues	260	647
Graphics [Member] | Software [Member]
Disaggregation Of Revenue [Line Items]
Revenues	$ 260	$ 647