Goodwill and Intangible Assets - Intangible Assets Other than Goodwill (Detail) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2019	Dec. 31, 2018
Indefinite-lived Intangible Assets [Line Items]
Not amortized intangible assets, Carrying Amount	$ 1,920	$ 1,858
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	23,925	26,727
Accumulated Amortization	(10,778)	(12,650)
Total	13,147	14,077
Intangible assets, Gross Carrying Amount	25,845	28,585
Intangible assets, Net Carrying Amount	15,067	15,935
TASER trademark
Indefinite-lived Intangible Assets [Line Items]
Not amortized intangible assets, Carrying Amount	900	900
Patents and trademarks pending
Indefinite-lived Intangible Assets [Line Items]
Not amortized intangible assets, Carrying Amount	1,020	958
Domain names
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	3,161	3,161
Accumulated Amortization	(808)	(732)
Total	$ 2,353	2,429
Domain names | Minimum
Finite-Lived Intangible Assets [Line Items]
Finite-lived intangible asset, useful life	5 years
Domain names | Maximum
Finite-Lived Intangible Assets [Line Items]
Finite-lived intangible asset, useful life	10 years
Issued patents
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	$ 2,982	2,940
Accumulated Amortization	(1,158)	(1,106)
Total	$ 1,824	1,834
Issued patents | Minimum
Finite-Lived Intangible Assets [Line Items]
Finite-lived intangible asset, useful life	4 years
Issued patents | Maximum
Finite-Lived Intangible Assets [Line Items]
Finite-lived intangible asset, useful life	15 years
Issued trademarks
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	$ 922	1,053
Accumulated Amortization	(490)	(599)
Total	$ 432	454
Issued trademarks | Minimum
Finite-Lived Intangible Assets [Line Items]
Finite-lived intangible asset, useful life	3 years
Issued trademarks | Maximum
Finite-Lived Intangible Assets [Line Items]
Finite-lived intangible asset, useful life	11 years
Customer relationships
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	$ 3,717	3,701
Accumulated Amortization	(1,027)	(880)
Total	$ 2,690	2,821
Customer relationships | Minimum
Finite-Lived Intangible Assets [Line Items]
Finite-lived intangible asset, useful life	4 years
Customer relationships | Maximum
Finite-Lived Intangible Assets [Line Items]
Finite-lived intangible asset, useful life	8 years
Non-compete agreements
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	$ 452	540
Accumulated Amortization	(375)	(439)
Total	$ 77	101
Non-compete agreements | Minimum
Finite-Lived Intangible Assets [Line Items]
Finite-lived intangible asset, useful life	3 years
Non-compete agreements | Maximum
Finite-Lived Intangible Assets [Line Items]
Finite-lived intangible asset, useful life	4 years
Developed technology
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	$ 10,660	13,404
Accumulated Amortization	(4,889)	(7,081)
Total	$ 5,771	6,323
Developed technology | Minimum
Finite-Lived Intangible Assets [Line Items]
Finite-lived intangible asset, useful life	3 years
Developed technology | Maximum
Finite-Lived Intangible Assets [Line Items]
Finite-lived intangible asset, useful life	7 years
Re-acquired distribution rights
Finite-Lived Intangible Assets [Line Items]
Finite-lived intangible asset, useful life	2 years
Gross Carrying Amount	$ 2,031	1,928
Accumulated Amortization	(2,031)	(1,813)
Total	$ 0	$ 115