Property and Equipment, Net (Tables)

3 Months Ended

Mar. 31, 2021

Property Plant And Equipment [Abstract]

Property and Equipment, Net

Property and equipment, net, consisted of the following:

	Estimated	March 31,			December 31,
	Useful Life	2021			2020
Lab and test equipment	7 years	$	19,017		$	18,631
Vehicles	5 years		14,047			13,320
Equipment	3–7 years		33,263			32,177
Furniture and fixtures	7 years		3,023			2,938
Leasehold improvements	7 years		6,884			6,767
Aircraft	10 years		834			834
Building	39 years		2,975			2,975
			80,043			77,642
Land			725			725
Construction in progress			489			219
Less accumulated depreciation			(46,316	)		(44,187	)
Total property and equipment—    net		$	34,941		$	34,399