Organization and Summary of Significant Accounting Policies - Additional Information (Detail)	12 Months Ended
	Dec. 31, 2017 USD ($) source subsidiary depository_institution segment shares	Dec. 31, 2016 USD ($) shares	Dec. 31, 2015 USD ($) shares	Dec. 31, 2012
Summary Of Significant Accounting Policy [Line Items]
Number of wholly owned subsidiaries | subsidiary	2
Impairment losses	$ 1,000,000	$ 0	$ 0
Number of revenue sources | source	2
Service term for services purchased	1 year
Advertising cost	$ 500,000	400,000	600,000
Warranty period	1 year
Research and development costs	$ 55,373,000	30,609,000	$ 23,614,000
Allowance for doubtful accounts	$ 754,000	$ 433,000
Number of depository institutions | depository_institution	4
Aggregate balances in depository institution accounts	$ 53,400,000
Accounts and notes receivable by customers one		14.50%
Cash surrender value of corporate-owned life insurance policies	$ 3,846,000	$ 3,240,000
Number of reportable segments of company | segment	2
New option granted (in shares) | shares	0	0	0
Retained earnings	$ 123,185,000	$ 118,275,000
Cumulative effect of applying a change in accounting principle		$ 178,000
Minimum
Summary Of Significant Accounting Policy [Line Items]
Service term for services purchased	1 year			3 years
Maximum
Summary Of Significant Accounting Policy [Line Items]
Service term for services purchased	5 years			5 years
Extended Product Warranty
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]
Period of extended warranty after expiration of standard warranty	1 year
Extended Product Warranty | Maximum
Summary Of Significant Accounting Policy [Line Items]
Period of extended warranty after expiration of standard warranty	5 years
Evidence. Com
Summary Of Significant Accounting Policy [Line Items]
Service term for services purchased		2 years 6 months
Taser 60 Plan
Summary Of Significant Accounting Policy [Line Items]
Service term for services purchased		5 years
Revenues	$ 40,700,000	$ 17,900,000	$ 0
Basic Cartridge Plan
Summary Of Significant Accounting Policy [Line Items]
Revenue recognition, installment purchase, agreement, term	5 years
Additional Paid-in Capital
Summary Of Significant Accounting Policy [Line Items]
Cumulative effect of applying a change in accounting principle		475,000
Additional Paid-in Capital | Accounting Standards Update 2016-09
Summary Of Significant Accounting Policy [Line Items]
Cumulative effect of applying a change in accounting principle		500,000
Retained Earnings
Summary Of Significant Accounting Policy [Line Items]
Cumulative effect of applying a change in accounting principle		(297,000)
Retained Earnings | Accounting Standards Update 2016-09
Summary Of Significant Accounting Policy [Line Items]
Cumulative effect of applying a change in accounting principle		$ (500,000)
Income tax effects allocated directly to equity, cumulative effect of change in accounting principle	$ 200,000
Pro Forma | Difference Between Revenue Guidance In Effect Before And After Topic 606 | Accounting Standards Update 2014-09 | Minimum
Summary Of Significant Accounting Policy [Line Items]
Retained earnings	15,000,000
Pro Forma | Difference Between Revenue Guidance In Effect Before And After Topic 606 | Accounting Standards Update 2014-09 | Maximum
Summary Of Significant Accounting Policy [Line Items]
Retained earnings	$ 25,000,000