Quarterly Financial Information (Unaudited) (Tables)

12 Months Ended

Dec. 31, 2018

Quarterly Financial Information Disclosure [Abstract]

Summary of Condensed Consolidated Statements of Operations

	Condensed Consolidated Statements of Operations
	2018
	Q1			Q2			Q3			Q4
				(in thousands, except per share data)
Revenue	$	20,678		$	19,203		$	16,694		$	16,839
Gross profit	$	5,200		$	3,261		$	3,359		$	3,690
Loss from operations	$	(2,478	)	$	(3,718	)	$	(2,132	)	$	(5,603	)
Net loss	$	(2,434	)	$	(3,683	)	$	(2,087	)	$	(5,533	)
Basic loss per share	$	(0.19	)	$	(0.29	)	$	(0.16	)	$	(0.43	)
Diluted loss per share	$	(0.19	)	$	(0.29	)	$	(0.16	)	$	(0.43	)
Shares used in per share calculations:
Basic		12,673			12,697			12,721			12,755
Diluted		12,673			12,697			12,721			12,755

	2017
	Q1		Q2			Q3			Q4
			(in thousands, except per share data)
Revenue	$	22,841	$	18,848		$	19,653		$	19,469
Gross profit	$	6,253	$	3,873		$	4,380		$	3,616
Income (loss) from operations	$	41	$	(2,619	)	$	(2,546	)	$	(4,297	)
Net income (loss)	$	202	$	(2,560	)	$	(2,468	)	$	(4,232	)
Basic income (loss) per share	$	0.02	$	(0.20	)	$	(0.20	)	$	(0.33	)
Diluted income (loss) per share	$	0.02	$	(0.20	)	$	(0.20	)	$	(0.33	)
Shares used in per share calculations:
Basic		12,550		12,577			12,607			12,640
Diluted		12,848		12,577			12,607			12,640

Summary of Condensed Consolidated Balance Sheets

	Condensed Consolidated Balance Sheets
	2018
	March 31		June 30		September 30		December 31
	(in thousands)
Cash, cash equivalents, restricted cash and short-term investments	$	21,435	$	17,861	$	17,271	$	16,940
Total current assets	$	39,913	$	35,514	$	32,102	$	29,996
Total assets	$	45,110	$	41,000	$	37,648	$	31,994
Total current liabilities	$	15,289	$	14,189	$	12,744	$	12,466
Total shareholders' equity	$	29,340	$	25,635	$	23,858	$	18,341

	2017
	March 31		June 30		September 30		December 31
	(in thousands)
Cash, cash equivalents, restricted cash and short-term investments	$	30,984	$	27,296	$	26,758	$	24,754
Total current assets	$	49,092	$	47,077	$	45,021	$	44,253
Total assets	$	54,403	$	52,395	$	50,247	$	49,434
Total current liabilities	$	14,310	$	14,445	$	14,351	$	17,427
Total shareholders' equity	$	39,206	$	37,099	$	35,238	$	31,430