Shareholders' Equity

3 Months Ended

Mar. 31, 2016

Shareholders’ Equity [Abstract]

Stockholders' Equity Note Disclosure [Text Block]

Shareholders' Equity

Equity Issuances

March 2016 Private Placement

On March 10, 2016, the Company entered into a securities purchase agreement with certain investors, pursuant to which the Company issued and sold in a private placement an aggregate of 1.4 million shares of common stock and two-year warrants to purchase up to an aggregate of 1.4 million shares of the Company's common stock, at an exercise price of $1.00 per share. The unit purchase price for a share of the Company's common stock and warrant to purchase one share of the Company's common stock was $0.705 per unit, with $1.0 million of gross proceeds received by the Company.

Aspire Purchase Agreements

In November 2015, the Company entered into a common stock purchase agreement (the "Purchase Agreement") with Aspire Capital Fund, LLC, an Illinois limited liability company (“Aspire Capital”), which provides that, subject to certain terms and conditions, Aspire Capital is committed to purchase up to an aggregate of $30 million of shares (limited to a maximum of approximately 11.0 million shares, unless stockholder approval is obtained or certain minimum sale price levels are reached) of the Company's common stock over a 24-month term. As consideration for entering into the Purchase Agreement, the Company issued 842,696 shares of its common stock to Aspire Capital. During the three months endedMarch 31, 2016, the Company issued 50,000 shares of common stock under the Purchase Agreement for gross proceeds of $0.03 million. Overall, as of March 31, 2016, the Company issued 1.1 million shares under the Purchase Agreement for gross proceeds of $0.3 million.

Under the Purchase Agreement, at the Company’s discretion, it may present Aspire Capital with purchase notices from time to time to purchase the Company’s common stock, provided certain price, trading volume and conditions, including Nasdaq trading requirements, are met. The purchase price for the shares of common stock is based upon one of two formulas set forth in the Purchase Agreement depending on the type of purchase notice the Company submits to Aspire Capital, and is based on market prices of the Company’s common stock (in the case of regular purchases) or a discount of 5% applied to volume weighted average prices (in the case of VWAP purchases), in each case as determined by parameters defined in the Purchase Agreements. We have filed a registration statement with the SEC and a related prospectus supplement that covers the offering of shares of our common stock subject to the Purchase Agreement, and therefore can initiate sales to Aspire Capital at any time.

We are party to two existing agreements with Aspire Capital (the "May 2015 Purchase Agreement" and the "March 2014 Purchase Agreement", or collectively, the "Previous Purchase Agreements"). The registration statement we previously filed with the SEC to cover offerings of shares of our common stock subject to the previous Purchase Agreements has expired, and we have not, and currently have no intention to include such shares in a registration statement filed with the SEC. Unless and until we include such shares in a registration statement filed with the SEC, we are unable to initiate sales to Aspire under the Previous Purchase Agreements.

Under the May 2015 Purchase Agreement, Aspire Capital is committed to purchase up to an aggregate of $30 million of shares. As consideration for entering into the May 2015 Purchase Agreement, the Company issued 364,837 shares of its common stock to Aspire Capital. The Company has not issued any additional shares under the May 2015 Purchase Agreement. Under the March 2014 Purchase Agreement, Aspire Capital is committed to purchase up to an aggregate of $30.0 million of shares. As consideration for entering into the March 2014 Purchase Agreement, the Company issued 150,000 shares of its common stock to Aspire Capital. The Company did not issued shares under the March 2014 Purchase Agreement during the three months endedMarch 31, 2016. Overall, the Company has issued 5.1 million shares under the March 2014 Purchase Agreement for gross proceeds of $20.3 million.

Stock Options and Warrants

The following table summarizes the activity for stock options and warrants for the three months endedMarch 31, 2016:

	Stock Options							Warrants
	Shares		Weighted Average Exercise Price		Weighted Average Remaining Contractual Term (Years)	Aggregate Intrinsic Value (In Thousands)		Shares		Weighted Average Exercise Price		Weighted Average Remaining Contractual Term (Years)	Aggregate Intrinsic Value (In Thousands)
Outstanding at December 31, 2015	6,663,480		$	6.46	6.88	$	0.1	3,214,033		$	13.72	1.26	$	—
Changes during the period:
Granted	1,552,875		$	0.62				1,418,440		$	1.00
Exercised	—		$	—				—		$	—
Forfeited	(442,466	)	$	3.79				—		$	—
Expired	(545,097	)	$	5.07				(27,000	)	$	14.50
Outstanding at March 31, 2016	7,228,792		$	5.48	7.35	$	202.7	4,605,473		$	9.80	1.31	$	—
Vested at March 31, 2016 or expected to vest in the future	7,020,566		$	5.59	7.29	$	189.3	4,605,473		$	9.80	1.31	$	—
Vested at March 31, 2016	4,995,506		$	7.15	6.42	$	52.4	4,605,473		$	9.80	1.31	$	—

Restricted Stock

During the three months endedMarch 31, 2016 and 2015, the Company issued restricted stock for services as follows (in thousands, except share data):

	Three Months Ended March 31,
	2016		2015
Number of Restricted Stock Issued	983,828		818,004
Value of Restricted Stock Issued	$	562.8	$	2,955.8

The weighted average estimated fair value of restricted stock issued for services in the three months endedMarch 31, 2016 and 2015 was $0.57 and $3.61 per share, respectively. The fair value of the restricted stock was determined using the Company’s closing stock price on the date of issuance.