Stock-Based Compensation (Tables)

6 Months Ended

Jun. 30, 2018

Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]

Schedule of assumptions used in estimation of fair value of the share-based payment awards on the grant date

	Six Months Ended
	June 30,
	2018			2017
Risk-free interest rate		2.2	%		1.6	%
Volatility		109.5	%		70.2	%
Expected life (years)		4.0			4.0
Dividend yield		—	%		—	%

Summary of option and RSU activity under Amended and Restated 2000 Stock Option and Equity Incentive Plan and Amended and Restated 2010 Equity Incentive Plan

A summary of option and RSU activity under the Company’s Amended and Restated 2010 Equity Incentive Plan (the Plan) is presented below (in thousands, except exercise price):

				Awards outstanding
							Weighted
	Shares						Average
	Available			Number of			Exercise
	for Grant			Shares			Prices
Balance at January 1, 2018		231			307		$	4.81
Additional shares authorized under the Plan		50			—			—
RSUs granted		(60	)		—			—
RSUs cancelled and returned to the Plan		1			—			—
Options granted		(40	)		40		$	1.28
Options cancelled and returned to the Plan		2			(2	)	$	23.47
Balance at March 31, 2018		184			345		$	4.30
Options cancelled and returned to the Plan		1			(1	)	$	9.40
Balance at June 30, 2018		185			344		$	4.27

Summary of RSU activity under the Plans

A summary of RSU activity under the Plan is presented below (in thousands, except for fair value):

				Weighted
				Average
	Number of			Grant-Date
	Shares			Fair Value
Non-vested shares at January 1, 2018		376		$	1.58
Granted		60		$	1.16
Vested		(133	)	$	2.11
Cancelled		(1	)	$	0.94
Non-vested shares at June 30, 2018		302		$	1.27

Summary of significant ranges of outstanding and exercisable options

The following table summarizes significant ranges of outstanding and exercisable options as of June 30, 2018 (in thousands, except contractual life and exercise price):

	Options Outstanding						Options Exercisable
			Weighted
			Average
			Remaining		Weighted				Weighted
			Contractual		Average				Average		Aggregate
	Number		Life		Exercise		Number		Exercise		Intrinsic
Range of Exercise Price	Outstanding		(in Years)		Price		Exercisable		Price		value
$0.75 - $1.27		160		5.30	$	0.75		—	$	—	$	160
$1.28 - $7.19		51		6.07	$	2.10		7	$	5.17	$	19
$7.20 - $20.49		112		8.01	$	7.20		70	$	7.20	$	—
$20.50 - $43.59		19		6.55	$	20.50		16	$	20.50	$	—
$44.60 - $46.19		1		4.93	$	44.60		1	$	44.60	$	—
$46.20 - $46.20		1		5.64	$	46.20		1	$	46.20	$	—
$0.75 - $46.20		344		6.37	$	4.27		95	$	9.68	$	179
Vested and expected to vest		322		6.42	$	4.45						162
Exercisable		94		7.68	$	9.68						—