Revenues - Schedule Of Contract Liabilities (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Disaggregation of Revenue [Line Items]
Current	$ 110,063	$ 107,016
Long-Term	74,784	74,417
Total	184,847	181,433
TASER
Disaggregation of Revenue [Line Items]
Current	15,741	22,152
Long-Term	32,299	32,445
Total	48,040	54,597
Software and Sensors
Disaggregation of Revenue [Line Items]
Current	94,322	84,864
Long-Term	42,485	41,972
Total	136,807	126,836
Warranty
Disaggregation of Revenue [Line Items]
Current	20,600	21,070
Long-Term	21,830	23,363
Total	42,430	44,433
Warranty | TASER
Disaggregation of Revenue [Line Items]
Current	11,821	12,797
Long-Term	15,770	16,847
Total	27,591	29,644
Warranty | Software and Sensors
Disaggregation of Revenue [Line Items]
Current	8,779	8,273
Long-Term	6,060	6,516
Total	14,839	14,789
Hardware
Disaggregation of Revenue [Line Items]
Current	34,949	30,233
Long-Term	40,114	40,283
Total	75,063	70,516
Hardware | TASER
Disaggregation of Revenue [Line Items]
Current	3,845	9,355
Long-Term	16,091	15,598
Total	19,936	24,953
Hardware | Software and Sensors
Disaggregation of Revenue [Line Items]
Current	31,104	20,878
Long-Term	24,023	24,685
Total	55,127	45,563
Software and Sensors
Disaggregation of Revenue [Line Items]
Current	54,514	55,713
Long-Term	12,840	10,771
Total	67,354	66,484
Software and Sensors | TASER
Disaggregation of Revenue [Line Items]
Current	75	0
Long-Term	438	0
Total	513	0
Software and Sensors | Software and Sensors
Disaggregation of Revenue [Line Items]
Current	54,439	55,713
Long-Term	12,402	10,771
Total	$ 66,841	$ 66,484