Organization and Summary of Significant Accounting Policies - Additional Information (Detail) $ in Thousands	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2017 USD ($) subsidiary	Sep. 30, 2016 USD ($)	Sep. 30, 2017 USD ($) Segment subsidiary Source	Sep. 30, 2016 USD ($)	Dec. 31, 2016 USD ($)
Summary Of Significant Accounting Policy [Line Items]
Number of wholly owned subsidiaries | subsidiary	2		2
Number of reportable segments | Segment			2
Number of revenue sources | Source			2
Warranty period			1 year
Corporate owned life insurance policies fair value	$ 3,723		$ 3,723		$ 3,240
Additional Paid-in Capital | Accounting Standards Update 2016-09
Summary Of Significant Accounting Policy [Line Items]
Cumulative effect of new accounting principle in period of adoption - APIC					500
Retained Earnings | Accounting Standards Update 2016-09
Summary Of Significant Accounting Policy [Line Items]
Cumulative effect of new accounting principle in period of adoption - APIC					$ (500)
Minimum
Summary Of Significant Accounting Policy [Line Items]
Service term for services purchased			3 years
Maximum
Summary Of Significant Accounting Policy [Line Items]
Service term for services purchased			5 years
Extended Product Warranty | Minimum
Summary Of Significant Accounting Policy [Line Items]
Extended warranty period			1 year
Service term for services purchased			1 year
Extended Product Warranty | Maximum
Summary Of Significant Accounting Policy [Line Items]
Extended warranty period			5 years
Service term for services purchased			5 years
Evidence. Com
Summary Of Significant Accounting Policy [Line Items]
Subscription period			5 years
Device upgrade period			2 years 6 months
Taser 60 Plan
Summary Of Significant Accounting Policy [Line Items]
Revenues	$ 7,500	$ 5,000	$ 20,800	$ 8,600
Installment purchase agreement, term			5 years
Customer Concentration Risk | Accounts Receivable | One customer
Summary Of Significant Accounting Policy [Line Items]
Concentration risk, percentage			10.30%		14.50%