Goodwill and Intangible Assets - Intangible Assets Other than Goodwill (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2015	Dec. 31, 2014	Mar. 31, 2014
Acquired Indefinite-lived Intangible Assets [Line Items]
Amortized intangible assets, gross carrying amount	$ 2,499		$ 2,450
Accumulated amortization	(912)		(868)
Total	1,587		1,582
Not amortized intangible assets, carrying amount	1,378		1,533
Intangible assets, gross carrying amount	3,877		3,983
Intangible assets, net carrying amount	2,965	3,115	3,115
TASER trademark
Acquired Indefinite-lived Intangible Assets [Line Items]
Not amortized intangible assets, carrying amount	900		900
Patents and trademarks pending
Acquired Indefinite-lived Intangible Assets [Line Items]
Not amortized intangible assets, carrying amount	478		633
Domain names
Acquired Indefinite-lived Intangible Assets [Line Items]
Amortized intangible assets, useful life	5 years
Amortized intangible assets, gross carrying amount	125		125
Accumulated amortization	(117)		(114)
Total	8		11
Issued patents
Acquired Indefinite-lived Intangible Assets [Line Items]
Amortized intangible assets, gross carrying amount	1,799		1,759
Accumulated amortization	(584)		(549)
Total	1,215		1,210
Issued patents | Minimum
Acquired Indefinite-lived Intangible Assets [Line Items]
Amortized intangible assets, useful life	4 years
Issued patents | Maximum
Acquired Indefinite-lived Intangible Assets [Line Items]
Amortized intangible assets, useful life	15 years
Issued trademarks
Acquired Indefinite-lived Intangible Assets [Line Items]
Amortized intangible assets, gross carrying amount	575		566
Accumulated amortization	(211)		(205)
Total	$ 364		$ 361
Issued trademarks | Minimum
Acquired Indefinite-lived Intangible Assets [Line Items]
Amortized intangible assets, useful life	9 years
Issued trademarks | Maximum
Acquired Indefinite-lived Intangible Assets [Line Items]
Amortized intangible assets, useful life	11 years