Stockholders' Equity - RSA and PSU Activity (Details)	6 Months Ended
	Jun. 30, 2018 $ / shares shares
2018 Omnibus Incentive Plan | Restricted Stock
Number of RSAs
Outstanding (in shares) | shares	0
Granted (in shares) | shares	1,522,034
Exercised (in shares) | shares	0
Forfeited or expired (in shares) | shares	0
Outstanding (in shares) | shares	1,522,034
Weighted-Average Stock Price
Outstanding, Weighted-Average Stock Price (in dollars per share) | $ / shares	$ 0.00
Granted, Weighted-Average Stock Price (in dollars per share) | $ / shares	4.18
Exercised, Weighted-Average Stock Price (in dollars per share) | $ / shares	0.00
Forfeited or expired, Weighted-Average Stock Price (in dollars per share) | $ / shares	0.00
Outstanding, Weighted-Average Stock Price (in dollars per share) | $ / shares	$ 4.18
2012 Omnibus Incentive Plan | Restricted Stock
Number of RSAs
Outstanding (in shares) | shares	2,292,308
Granted (in shares) | shares	449,500
Exercised (in shares) | shares	(954,529)
Forfeited or expired (in shares) | shares	(209,600)
Outstanding (in shares) | shares	1,577,679
Weighted-Average Stock Price
Outstanding, Weighted-Average Stock Price (in dollars per share) | $ / shares	$ 3.77
Granted, Weighted-Average Stock Price (in dollars per share) | $ / shares	2.17
Exercised, Weighted-Average Stock Price (in dollars per share) | $ / shares	3.72
Forfeited or expired, Weighted-Average Stock Price (in dollars per share) | $ / shares	2.99
Outstanding, Weighted-Average Stock Price (in dollars per share) | $ / shares	$ 3.45
2012 Omnibus Incentive Plan | Performance Shares
Number of RSAs
Outstanding (in shares) | shares	0
Granted (in shares) | shares	615,500
Exercised (in shares) | shares	0
Forfeited or expired (in shares) | shares	0
Outstanding (in shares) | shares	615,500
Weighted-Average Stock Price
Outstanding, Weighted-Average Stock Price (in dollars per share) | $ / shares	$ 0.00
Granted, Weighted-Average Stock Price (in dollars per share) | $ / shares	2.94
Exercised, Weighted-Average Stock Price (in dollars per share) | $ / shares	0.00
Forfeited or expired, Weighted-Average Stock Price (in dollars per share) | $ / shares	0.00
Outstanding, Weighted-Average Stock Price (in dollars per share) | $ / shares	$ 2.94
The Amended and Restated 2016 Inducement Omnibus Incentive Plan | Restricted Stock
Number of RSAs
Outstanding (in shares) | shares	1,242,250
Granted (in shares) | shares	0
Exercised (in shares) | shares	(240,540)
Forfeited or expired (in shares) | shares	(295,877)
Outstanding (in shares) | shares	705,833
Weighted-Average Stock Price
Outstanding, Weighted-Average Stock Price (in dollars per share) | $ / shares	$ 4.62
Granted, Weighted-Average Stock Price (in dollars per share) | $ / shares	0.00
Exercised, Weighted-Average Stock Price (in dollars per share) | $ / shares	5.36
Forfeited or expired, Weighted-Average Stock Price (in dollars per share) | $ / shares	5.39
Outstanding, Weighted-Average Stock Price (in dollars per share) | $ / shares	$ 4.05