Revenue (Tables)

12 Months Ended

Dec. 31, 2020

Revenue From Contract With Customer [Abstract]

Schedule of Performance Obligation

Total Net Sales Based on Disaggregation Criteria

Total net sales based on the disaggregation criteria described above are as follows (in thousands):

	Year Ended December 31,
	2020						2019
	Point-in-						Point-in-
	Time		Over Time		Total		Time		Over Time		Total
Americas	$	54,491	$	3,811	$	58,302	$	56,461	$	4,904	$	61,365
Europe and the Middle East		9,124		373		9,497		11,078		339		11,417
Asia-Pacific		19,121		—		19,121		10,973		—		10,973
Total	$	82,736	$	4,184	$	86,920	$	78,512	$	5,243	$	83,755

Changes in Deferred Revenue

Changes in deferred revenue during the years ended December 31, 2020 and 2019 were as follows (in thousands):

	Year Ended December 31,
	2020			2019
Deferred revenue, beginning of period	$	2,833		$	2,810
Deferral of revenue billed in current period, net of recognition		1,591			2,149
Recognition of revenue deferred in prior periods		(2,058	)		(2,126	)
Deferred revenue as, end of period	$	2,366		$	2,833