Organization and Description of the Business (Details Textual) (USD $)	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014	Dec. 31, 2014
Organization And Description Of The Business [Line Items]
Retained Earnings (Accumulated Deficit)	$ (376,499,000)		$ (362,006,000)
Net proceeds from March 2015 financing, gross	13,000,000
Net proceeds from March 2015 financing, net	$ 12,384,000	$ 0