Stock-Based Compensation (Tables)

6 Months Ended

Jun. 30, 2021

Share Based Compensation Arrangement By Share Based Payment Award [Line Items]

Summary of Stock Option Activity

The following is a summary of stock option activity for the six months ended June 30, 2021:

	Number Outstanding			Average Exercise Price per Share		Weighted Average Remaining Contractual Term (Years)		Aggregate Intrinsic Value
Balance at December 31, 2020		550,769		$	5.56		4.88	$	1,875,719
Granted		—			—
Cancelled or Expired		(792	)		20.21
Exercised		(16,651	)		8.19
Balance at June 30, 2021		533,326		$	5.46		4.49	$	6,182,448
Vested or expected to vest at     June 30, 2021		533,326		$	5.46		4.49	$	6,182,448
Exercisable at June 30, 2021		533,326		$	5.46		4.49	$	6,182,448

Summary Information about Stock Options Outstanding

The following table summarizes information about stock options outstanding as of June 30, 2021:

	Stock Options Outstanding						Stock Options Exercisable
Range of Exercise Prices	Number Outstanding		Weighted Average Remaining Contractual Life (Years)		Weighted Average Exercise Price		Number Exercisable		Weighted Average Exercise Price
$4.36 - $7.20		454,010		4.87	$	4.41		454,010	$	4.41
$7.50 - $11.25		61,817		2.73		10.17		61,817		10.17
$11.30 - $16.95		11,302		1.23		13.03		11,302		13.03
$17.60 - $26.40		6,197		0.27		21.38		6,197		21.38
$4.36 - $26.40		533,326		4.49	$	5.46		533,326	$	5.46

Summary of Stock Unit Activity

The following is a summary of RSU activity for the six months ended June 30, 2021:

	Number Outstanding			Weighted Average Fair Value
Unvested at December 31, 2020		682,563		$	4.34
Granted		136,356			12.20
Vested		(257,440	)		5.33
Forfeited		(42,973	)		4.32
Unvested at June 30, 2021		518,506		$	5.92
RSUs vested but not released		286,211		$	4.94

Stock-Based Compensation Expense Related to Stock Options, RSUs and PSUs

The following table summarizes stock-based compensation expense related to stock options, RSUs, and PSUs included in the condensed consolidated statements of comprehensive income (loss) for the three and six months ended June 30, 2021 and 2020 (in thousands):

	Three Months Ended June 30,				Six Months Ended June 30,
	2021		2020		2021		2020
Cost of revenue	$	48	$	41	$	81	$	81
Research and development		93		173		255		347
Selling and marketing		124		118		227		244
General and administrative		432		419		892		719
Total	$	697	$	751	$	1,455	$	1,391

Performance Stock Units

Share Based Compensation Arrangement By Share Based Payment Award [Line Items]

Summary of Stock Unit Activity

The following is a summary of PSU activity for the six months ended June 30, 2021:

	Number Outstanding
Unvested at December 31, 2020		200,000
Granted		—
Vested		(23,500	)
Forfeited		—
Unvested at June 30, 2021		176,500