Management's Plan (Details Textual) - USD ($) $ in Thousands	Jun. 30, 2016	Dec. 31, 2015	Jun. 30, 2015	Dec. 31, 2014
Management's Plan [Line Items]
Accumulated deficit	$ (161,305)	$ (144,779)
Cash and Cash Equivalents, at Carrying Value, Total	$ 10,049	$ 20,818	$ 4,757	$ 17,525