Significant Concentrations (Tables)

12 Months Ended

Dec. 31, 2018

Risks And Uncertainties [Abstract]

Summary of Revenue and Accounts Receivable

Honeywell International, Inc. and affiliated entities (“Honeywell”) accounted for revenue and accounts receivable as follows (in thousands, except percentages):

	Year Ended December 31,
	2018			2017
Honeywell revenue	$	7,013		$	12,278
As a percentage of total revenue		10	%		15	%
	December 31,
	2018			2017
Honeywell accounts receivable	$	2,758		$	8,659
As a percentage of total accounts receivable		24	%		48	%

Summary of Rebate Program Recorded Under Rebate Credits

Under this rebate program, we recorded rebate credits as follows (in thousands):

	Year Ended December 31,
	2018		2017
Reductions to cost of revenue	$	718	$	499
Reductions to marketing expense	$	682	$	658