Stockholders' Equity (Tables)

12 Months Ended

Dec. 31, 2016

Equity [Abstract]

Summary of Outstanding Warrants Issued by Company

Below is a summary of outstanding warrants issued by the Company as of December 31, 2016:

Warrant Type	Number of Shares Issuable Upon Exercise		Weighted Average Exercise Price		Issue Date	Expiration Date
Consultant Warrant		85,000	$	10.70	August 13, 2014	August 13, 2019
Opus Warrant		200,000		2.19	March 31, 2014	March 31, 2019
New Opus Warrant #1		100,000		2.22	September 30, 2016	September 30, 2021
New Opus Warrant #2		100,000		3.61	December 31, 2016	December 31, 2021
2013 Private Placement Warrants		186,878		10.00	August 14, 2013	August 14, 2017
Total		671,878

Summary of Activity under Stock-Based Compensation Plans

A summary of activity for the Company’s stock option plans for the year ended December 31, 2016 follows:

	Number Outstanding			Average Exercise Price per Share		Weighted Average Remaining Contractual Term (Years)		Average Intrinsic Value
Balance at December 31, 2015		781,804		$	11.48			$	—
Granted		444,460			4.36
Cancelled or Expired		(393,323	)		12.15
Exercised		—			—
Balance at December 31, 2016		832,941		$	7.11		8.23	$	—
Vested or expected to vest at    December 31, 2016		801,667		$	7.18		8.19	$	—
Exercisable at December 31, 2016		429,816		$	8.58		7.58	$	—

Summary Information about Options Outstanding

The following table summarizes information about options outstanding as of December 31, 2016:

	Options Outstanding						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		530,810		9.00	$	4.55		207,619	$	4.78
$7.50 - $11.30		254,471		7.25		9.80		174,537		9.67
$12.00 - $19.70		27,390		6.29		13.66		27,390		13.66
$21.70 - $33.90		17,541		3.23		29.30		17,541		29.30
$34.40 - $43.40		2,729		0.22		43.40		2,729		43.40
$4.36 - $43.40		832,941		8.23	$	7.11		429,816	$	8.58

Weighted-average Assumptions Used in Estimating Fair Value of Option Grants by Using Black-Scholes Model

The fair value of option grants was estimated using the Black-Scholes model with the following weighted-average assumptions for the years ended December 31, 2016:

	2016		2015
Risk-free interest rate		1.25%	N/A
Expected volatility		78.40%	N/A
Expected term in years	4.77		N/A
Dividend yield		0.00%	N/A

At December 31, 2016, there was $1.4 million of unrecognized stock-based compensation expense, net of estimated forfeitures related to unvested options, that is expected to be recognized over a weighted-average period of 2.1 years.  

Summary of Restricted Stock and Restricted Stock Unit (RSU) Activity

The following is a summary of restricted stock and restricted stock unit (“RSU”) activity for the year ended December 31, 2016:

	Number Outstanding			Weighted Average Fair Value
Balance at December 31, 2015		721,918		$	13.32
Granted		2,252,732			2.19
Vested		(736,922	)		6.56
Forfeited		(264,269	)		14.64
Balance at December 31, 2016		1,973,459		$	2.80

Stock-Based Compensation Expense Related to Stock Options and RSUs

The following table illustrates all stock-based compensation expense related to stock options and RSUs included in the consolidated statements of operations for the years ended December 31, 2016 and 2015 (in thousands):

	Year Ended December 31,
	2016		2015
Cost of revenue	$	76	$	85
Research and development		352		324
Selling and marketing		632		1,085
General and administrative		1,782		3,022
Total	$	2,842	$	4,516

Schedule of Common Stock Reserved for Future Issuance

Common stock reserved for future issuance as of December 31, 2016 was as follows:

Exercise of outstanding stock options and vesting of RSUs	2,806,215
ESPP	293,888
Shares of common stock available for grant under the 2011 Plan	330,979
Noncontrolling interest in Bluehill AG	10,355
Warrants to purchase common stock	671,878
Total	4,113,315