Significant Risk Concentrations (Tables)

6 Months Ended

Jun. 30, 2019

Risks And Uncertainties [Abstract]

Summary of Rebate Program Recorded Under Rebate Credits

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

	Three Months Ended June 30,				Six Months Ended June 30,
	2019		2018		2019		2018
Reductions to cost of revenue	$	71	$	158	$	153	$	418
Reductions to marketing expense	$	16	$	113	$	430	$	379