Stock-Based Compensation (Details 3) - Non Vested	12 Months Ended
	Dec. 31, 2017 $ / shares shares
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward]
Non-vested options at beginning of period (in shares) | shares	1,441,166
Options, granted (in shares) | shares	577,845
Option, Vested (in shares) | shares	(654,156)
Options, Forfeited (in shares) | shares	(180,511)
Non-vested options at end of period (in shares) | shares	1,184,344
Share-based Compensation Arrangement by Share-based Payment Award, Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract]
Non-vested options at beginning of period (in dollars per share) | $ / shares	$ 3.58
Granted (in dollars per share) | $ / shares	3.37
Vested (in dollars per share) | $ / shares	3.62
Forfeited (in dollars per share) | $ / shares	3.46
Non-vested options at end of period (in dollars per share) | $ / shares	$ 3.48