Summary of Significant Accounting Policies (Narrative) (Details) - USD ($) $ in Thousands, shares in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Property, Plant and Equipment [Line Items]
Net Income (Loss) Attributable to Parent	$ (11,833)	$ (10,474)	$ (10,650)	$ (8,955)	$ (6,849)	$ (5,052)	$ (4,284)	$ (5,128)	$ (41,912)	$ (21,313)	$ (17,935)
Potentially dilutive common shares related to the outstanding preferred stock, stock options, restricted stock units and warrants									10.0	8.2	13.1
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