Business Acquisitions - Summary of Assets Acquired and Liabilities Assumed (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Jul. 01, 2017	Feb. 08, 2017	Dec. 31, 2016	Dec. 30, 2016
Business Acquisition [Line Items]
Goodwill	$ 14,927			$ 10,442
Axon Artificial Intelligence
Business Acquisition [Line Items]
Goodwill					$ 1,615
Total purchase price					6,825
Dextro, Inc.
Business Acquisition [Line Items]
Accounts receivable			$ 12
Property and equipment			46
Goodwill			2,703
Deferred income tax liabilities, net			(1,074)
Total purchase price			7,487
Breon Enterprises
Business Acquisition [Line Items]
Goodwill		$ 1,650
Total purchase price		4,150
Developed technology | Axon Artificial Intelligence
Business Acquisition [Line Items]
Intangible assets other than goodwill acquired					$ 5,210
Developed technology | Dextro, Inc.
Business Acquisition [Line Items]
Intangible assets other than goodwill acquired			$ 5,800
Re-acquired distribution rights | Breon Enterprises
Business Acquisition [Line Items]
Intangible assets other than goodwill acquired		2,100
Customer relationships | Breon Enterprises
Business Acquisition [Line Items]
Intangible assets other than goodwill acquired		$ 400