Summary of Significant Accounting Policies (Narrative) (Details) $ in Thousands, shares in Millions		3 Months Ended		9 Months Ended
	Jan. 14, 2014	Sep. 30, 2015 USD ($)	Sep. 30, 2014 USD ($)	Sep. 30, 2015 USD ($) shares	Sep. 30, 2014 USD ($) shares	Dec. 31, 2014 USD ($)
Property, Plant and Equipment [Line Items]
Reverse stock split ratio	0.02
Restricted cash		$ 237		$ 237		$ 37
Property and equipment, net		1,751		1,751		279
Depreciation expense		114	$ 5	209	$ 10
Prepaid clinical expenses		360		$ 360		$ 1,528
Potentially dilutive common shares related to the outstanding preferred stock, stock options, restricted stock units and warrants | shares				9.1	8.1
Comprehensive loss		$ (10,474)	$ (5,052)	$ (30,079)	$ (14,464)
Minimum [Member]
Property, Plant and Equipment [Line Items]
Estimated useful lives of the assets				2 years
Maximum [Member]
Property, Plant and Equipment [Line Items]
Estimated useful lives of the assets				7 years