Consolidated Statements of Operations - USD ($) shares in Thousands, $ in Thousands		3 Months Ended
		Mar. 31, 2020	Mar. 31, 2019
Sales:
Net sales		$ 36,568	$ 36,376
Costs and expenses:
Cost of goods and services sold			8,284
Research and development		4,287	3,868
Sales, marketing and support		8,700	8,130
General and administrative		6,398	6,955
Total costs and expenses		44,216	42,610
Loss from operations		(7,648)	(6,234)
Interest income		313	175
Interest expense		4	385
Other income (expense), net		1,502	(97)
Loss from continuing operations before income tax expense (benefit)		(5,837)	(6,541)
Income tax expense (benefit)		377	(44)
Net loss from continuing operations		(6,214)	(6,497)
Income from discontinued operations, net of tax		0	243
Net loss		$ (6,214)	$ (6,254)
Net loss from continuing operations per common share
Basic and diluted (in USD per share)	[1]	$ (0.35)	$ (0.38)
Net income from discontinued operations per common share
Basic and diluted (in USD per share)	[1]	0	0.01
Net loss per common share
Basic and diluted (in USD per share)	[1]	$ (0.35)	$ (0.36)
Weighted average number of common shares outstanding:
Basic and diluted (in shares)		17,529	17,302
Product
Sales:
Net sales		$ 13,094	$ 13,215
Costs and expenses:
Cost of goods and services sold		9,636	8,284
Service
Sales:
Net sales		23,474	23,161
Costs and expenses:
Cost of goods and services sold		$ 15,195	$ 15,373

[1] Earnings per share components for 2019 do not sum due to rounding.