Liquidity (Narrative) (Details) - USD ($)	63 Months Ended
	Mar. 31, 2016	Dec. 31, 2015	Mar. 31, 2015	Dec. 31, 2014
Liquidity [Abstract]
Retained earnings (accumulated deficit)	$ (365,634,000)	$ (362,522,000)
Retained earnings (accumulated deficit) during period	(50,100,000)
Cash and cash equivalents	$ 6,173,000	$ 9,370,000	$ 16,625,000	$ 6,581,000