Stockholders' Equity (Details 2) (USD $) In Millions, except Share data, unless otherwise specified	3 Months Ended
	Jun. 30, 2013
Warrants
Gross proceeds from public offering	$ 5.0
Underwriters' commissions	0.9
Common Stock
Warrants
Net proceeds from public offering	2.1
Warrant
Warrants
Warrants issued (in shares)	61,492,785
Warrants outstanding (in shares)	61,492,785
Net proceeds from public offering	$ 2.0
Warrant | Minimum
Warrants
Exercise price (in dollars per share)	$ 0.12
Exercise period	1 month 6 days
Warrant | Maximum
Warrants
Exercise price (in dollars per share)	$ 4.25
Exercise period	5 years 10 months 24 days