Net Loss per Common Share Applicable to Common Stockholders (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Net Loss per Common Share Applicable to Common Stockholders
Total antidilutive securities	69,712,906	70,782,788	74,640,383
Preferred stock dividends			$ 519