Basic and Diluted Net Loss per Common Share (Details) - shares shares in Thousands	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Potential common shares excluded because such instruments were anti-dilutive (in shares)	18,659	86
Stock options
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Potential common shares excluded because such instruments were anti-dilutive (in shares)	1,595	86
Unvested restricted stock units
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Potential common shares excluded because such instruments were anti-dilutive (in shares)	930	0
Warrants
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Potential common shares excluded because such instruments were anti-dilutive (in shares)	14,515	0
Convertible notes
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Potential common shares excluded because such instruments were anti-dilutive (in shares)	1,619	0