Stock-Based Compensation and Warrants (Tables)

3 Months Ended

Mar. 31, 2019

Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]

Summary of Activity Under Stock Incentive Plans

A summary of activity under the stock incentive plans is as follows (in thousands, except share data and price per share):

	Shares Subject to Outstanding Options			Weighted- Average Exercise Price Per Share		Aggregate Intrinsic Value
Outstanding — Balance at December 31, 2018		530,044		$	35.53	$	—
Options granted		7,500			3.57
Options exercised		—			—
Options forfeited		(1,287	)		4.33
Options expired		(1,014	)	$	24.78
Outstanding — Balance at March 31, 2019		535,243		$	35.13	$	637
Vested and expected to vest — March 31, 2019		526,131		$	35.47	$	623
Exercisable —March 31, 2019		231,086		$	60.40	$	182

Weighted-Average Fair Value Assumption of Stock Option Awards

The fair value of stock option awards to executives and other service providers was estimated at the date of grant using the Black-Scholes Model with the following weighted-average assumption. There were 7,500 and 10,000 options granted during the three months ended March 31, 2019 and 2018, respectively.

	Three Months Ended March 31,
		2019		2018
Expected term (years)		2.58		6.25
Expected volatility		133	%	100	%
Risk-free interest rate		2.55	%	2.73	%
Dividend yield		—		—