Significant Concentrations (Tables)

12 Months Ended

Dec. 31, 2017

Risks And Uncertainties [Abstract]

Summary of Revenue and Accounts Receivable

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

	Year Ended December 31,
	2017			2016
Honeywell revenue	$	12,278		$	13,696
As a percentage of total revenue		15	%		14	%
	December 31,
	2017			2016
Honeywell accounts receivable	$	8,659		$	7,075
As a percentage of total accounts receivable		48	%		33	%

Summary of Rebate Program Recorded Under Rebate Credits

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

	Year Ended December 31,
	2017		2016
Reductions to cost of revenue	$	499	$	345
Reductions to marketing expense	$	658	$	1,085