Stockholders' Equity (Tables)

12 Months Ended

Dec. 31, 2020

Share-based Payment Arrangement [Abstract]

Share-based compensation expense included in costs and expenses

	Years Ended December 31,
	2020		2019		2018
	(in thousands)
Share-based compensation expense:
Cost of revenues	$	—	$	—	$	23
Sales and marketing		116		304		982
Technology support		81		197		1,247
General and administrative		1,787		1,901		2,615
Share-based compensation expense		1,984		2,402		4,867
Amount capitalized to internal use software		—		—		1
Total share-based compensation expense	$	1,984	$	2,402	$	4,866

Fair value of stock options granted using the following weighted average assumptions

	Years Ended December 31,
	2020			2019			2018
Expected volatility		74	%		65	%		68	%
Expected risk-free interest rate		0.9	%		2.2	%		2.6	%
Expected life (years)		4.6			4.4			4.5

Outstanding stock options

	Number of Options			Weighted Average Exercise Price per Share		Weighted Average Remaining Contractual Term		Aggregate Intrinsic Value
							(years)		(thousands)
Outstanding at December 31, 2019		4,361,606		$	5.80		4.8	$	37
Granted		635,000			2.15
Exercised		(22,373	)		3.35				29
Forfeited or expired		(1,215,563	)		8.72
Outstanding at December 31, 2020		3,758,670		$	4.26		4.7	$	270
Vested and expected to vest at December 31, 2020		3,625,650		$	4.31		4.7	$	254
Exercisable at December 31, 2020		2,323,528		$	5.12		4.2	$	47

Shares reserved for issuance

	Number of Shares
Stock options outstanding		3,758,670
Authorized for future Award grants under stockholder-approved stock-based incentive plans		2,497,070
Warrants outstanding		1,482,400
Total		7,738,140