Subsequent Event (Details)					6 Months Ended
		Jul. 29, 2015 USD ($)	Jul. 22, 2015 USD ($) $ / shares shares	Jul. 09, 2015 USD ($) d	Jun. 30, 2015 USD ($) Event $ / shares shares
Subsequent Event [Line Items]
Number of subsequent events | Event					2
Warrants outstanding					13,200,000
Cash interest rate under loan facility (in hundredths)					8.75%
Principal amount of loan payable, prepayment amount | $					$ 10,000,000
Shares (in shares)					136,000,000
Deerfield Debt Restructuring [Member]
Subsequent Event [Line Items]
Deferred period for loan payment					1 year
February 2011 Warrants [Member]
Subsequent Event [Line Items]
Warrants outstanding					4,600,000
Exercise price (in dollars per share) | $ / shares					$ 1.50
Expiration date					Feb. 22, 2016
Subsequent Event [Member]
Subsequent Event [Line Items]
Gross proceeds from issuance of units | $			$ 40,250,000
Net proceeds from issuance of units | $			37,600,000
Non-cash consideration received | $			$ 5,000,000
Class of warrants may not exercise to extent (in hundredths)			9.99%
Class of warrants exercise may be elected by holders (in hundredths)			4.99%
Subsequent Event [Member] | Deerfield Debt Restructuring [Member]
Subsequent Event [Line Items]
Non-cash consideration received | $			$ 5,000,000
Prepayment of principal amount of loan outstanding | $			2,500,000	$ 2,500,000
Additional right to prepayment of principal amount of loan outstanding | $				$ 2,500,000
Number of days following a strategic transaction for prepayment of debt | d				5
Principal amount of loan outstanding payable in February 2018 | $			12,500,000	$ 12,500,000
Principal amount of loan outstanding payable in February 2019 | $			12,500,000	12,500,000
Counsel fee and expenses | $				$ 15,000
Principal amount of loan payable, future interest obligation | $			$ 5,000,000
Cash interest rate under loan facility (in hundredths)			8.25%
Principal amount of loan payable, prepayment amount | $		$ 12,500,000	$ 5,000,000
Remaining interest due on the principal amount outstanding (in hundredths)			8.25%
Common stock valuation prior to change in control | $			$ 100,000,000
Subsequent Event [Member] | Series A Units [Member]
Subsequent Event [Line Items]
Issuance of common stock (in shares)			25,083,332
Sale of unit price per unit (in dollars per share) | $ / shares			$ 0.60
Subsequent Event [Member] | Series A Units [Member] | Over-Allotment [Member]
Subsequent Event [Line Items]
Issuance of common stock (in shares)			8,749,999
Subsequent Event [Member] | Series B Units [Member]
Subsequent Event [Line Items]
Number of pre-funded warrants issued during the period (in shares)			42,000,000
Sale of unit price per unit (in dollars per share) | $ / shares			$ 0.60
Number of warrants required to purchase one share of common stock (in shares)			1
Subsequent Event [Member] | February 2011 Warrants [Member]
Subsequent Event [Line Items]
Exercise price (in dollars per share) | $ / shares			$ 0.19
Subsequent Event [Member] | Common Stock [Member] | Series A Units [Member]
Subsequent Event [Line Items]
Number of warrants required to purchase one share of common stock (in shares)			1
Subsequent Event [Member] | Common Stock [Member] | Series A Warrant [Member]
Subsequent Event [Line Items]
Number of warrants required to purchase one share of common stock (in shares)			1
Subsequent Event [Member] | Common Stock [Member] | Series B Units [Member]
Subsequent Event [Line Items]
Number of warrants required to purchase one share of common stock (in shares)			1
Subsequent Event [Member] | Common Stock [Member] | Series B Warrant [Member]
Subsequent Event [Line Items]
Number of warrants required to purchase one share of common stock (in shares)			1
Subsequent Event [Member] | Warrant [Member]
Subsequent Event [Line Items]
Shares (in shares)			122,326
Subsequent Event [Member] | Warrant [Member] | Investors - February 2011 Financing [Member]
Subsequent Event [Line Items]
Shares (in shares)			4,550
Exercise price (in dollars per share) | $ / shares			$ 0.19
Expiration date			Feb. 22, 2016
Subsequent Event [Member] | Warrant [Member] | Investors - July 2015 Financing (Pre-funded) [Member]
Subsequent Event [Line Items]
Shares (in shares)	[1]		42,000
Exercise price (in dollars per share) | $ / shares	[1]		$ 0.60
Expiration date	[1]		Jul. 22, 2022
Subsequent Event [Member] | Warrant [Member] | Investors - July 2015 Financing [Member]
Subsequent Event [Line Items]
Shares (in shares)			67,083
Exercise price (in dollars per share) | $ / shares			$ 0.70
Expiration date			Jul. 22, 2022
Subsequent Event [Member] | Warrant [Member] | Deerfield - 2013 Loan [Member]
Subsequent Event [Line Items]
Shares (in shares)			7,000
Exercise price (in dollars per share) | $ / shares			$ 2.81
Expiration date			Feb. 13, 2019
Subsequent Event [Member] | Warrant [Member] | Battelle - 2014 Collaboration Agreement [Member]
Subsequent Event [Line Items]
Shares (in shares)			1,500
Exercise price (in dollars per share) | $ / shares			$ 5.00
Expiration date			Oct. 10, 2024
Subsequent Event [Member] | Warrant [Member] | Former Employee [Member]
Subsequent Event [Line Items]
Shares (in shares)			30
Exercise price (in dollars per share) | $ / shares			$ 3.20
Expiration date			Mar. 18, 2016
Subsequent Event [Member] | Warrant [Member] | Pharmabio - October 2010 Financing [Member]
Subsequent Event [Line Items]
Shares (in shares)			80
Exercise price (in dollars per share) | $ / shares			$ 4.10
Expiration date			Oct. 13, 2015
Subsequent Event [Member] | Warrant [Member] | Kingsbridge - June 2010 Ceff [Member]
Subsequent Event [Line Items]
Shares (in shares)			83
Exercise price (in dollars per share) | $ / shares			$ 6.69
Expiration date			Dec. 11, 2015

[1] Investors in these warrants fully prepaid the $0.60 exercise price at the time of issuance.