Common Stock (Narrative) (Details) (USD $)	1 Months Ended				1 Months Ended
	Feb. 28, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011	May 31, 2012 May 2012	Jun. 30, 2012 June 2012	May 31, 2013 May 2013	Sep. 30, 2013 September 2013
Number of shares of common stock issued	3,713,309				3.3	4.2	2.6	3.5
Cash received from stock sale and warrants before issuance costs					$ 5,000,000	$ 10,500,000	$ 5,850,000	$ 6,600,000
Stock issuance costs					$ 71,000	$ 823,000	$ 362,000	$ 452,000
Common shares underlying warrants		8,091,000	5,131,000	2,287,000	1.0	2.1	2.0	2.1