Earnings Per Share - Anti-dilutive Shares (Details) - $ / shares			1 Months Ended					3 Months Ended		12 Months Ended
	Dec. 22, 2016	May 16, 2013	Apr. 30, 2017	Dec. 31, 2016	Jan. 31, 2014	Feb. 28, 2013	May 31, 2011	Mar. 31, 2017	Mar. 31, 2016	Dec. 31, 2013	Apr. 12, 2017	Apr. 05, 2017
Earnings Per Share
Number of dilutive potential common shares								44,475,506	21,526,612
Stock options
Earnings Per Share
Stock options granted								136,352	15,000
Subsequent event
Earnings Per Share
Exercise price of warrants (in dollars per share)											$ 2.69
Warrants issued in May, 2011
Earnings Per Share
Number of warrants issued (in shares)							7,128,563
Warrants outstanding (in shares)							22,995,365
Number of warrants unexercised (in shares)								0	74,188
Exercise price of warrants (in dollars per share)							$ 0.93
Warrants issued in February, 2013
Earnings Per Share
Number of warrants issued (in shares)						23,637,500
Number of warrants unexercised (in shares)								100	100
Exercise price of warrants (in dollars per share)						$ 0.15
Warrants issued in January, 2014
Earnings Per Share
Number of warrants issued (in shares)					4,000,000
Exercise price of warrants (in dollars per share)					$ 4.00
Warrants issued in January, 2014 | Subsequent event
Earnings Per Share
Exercise price of warrants (in dollars per share)			$ 0.65
Warrants issued in December 2016
Earnings Per Share
Number of warrants issued (in shares)				10,501,500
Number of warrants exercised (in shares)								0
Exercise price of warrants (in dollars per share)				$ 1.50
Warrants issued in December 2016 | Subsequent event
Earnings Per Share
Number of warrants exercised (in shares)			10,501,500
Exercise price of warrants (in dollars per share)											$ 1.50
Series C redeemable convertible preferred stock.
Earnings Per Share
Stock options granted		10,431
Number of preferred shares that had been converted to common stock										5,200
Series D Redeemable Convertible Preferred Stock
Earnings Per Share
Stock options granted	18,500
Number of preferred shares that had been converted to common stock								3,700
Series D Redeemable Convertible Preferred Stock | Subsequent event
Earnings Per Share
Exercise price of warrants (in dollars per share)												$ 1.55
Stock options
Earnings Per Share
Number of dilutive potential common shares								14,857,592	11,693,286
Restricted stock
Earnings Per Share
Number of dilutive potential common shares								13,333	204,444
Warrants
Earnings Per Share
Number of dilutive potential common shares								14,501,600	4,074,288
Preferred stock
Earnings Per Share
Number of dilutive potential common shares								15,102,981	5,554,594