Stock-Based Compensation (Details 2)	3 Months Ended
	Mar. 31, 2017 $ / shares shares
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Stock Options Outstanding (in shares) | shares	4,454,261
Weighted Average Exercise Price (in dollars per share)	$ 4.95
Weighted Average Remaining Contractual Life	6 years 10 months 17 days
Stock Options Exercisable (in shares) | shares	3,070,877
Weighted Average Exercise Price (in dollars per share)	$ 3.71
$0.79 - $1.00
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Exercise Price Range, Lower Range Limit (in dollars per share)	0.79
Exercise Price Range, Upper Range Limit (in dollars per share)	$ 1.00
Stock Options Outstanding (in shares) | shares	50,000
Weighted Average Exercise Price (in dollars per share)	$ 0.79
Weighted Average Remaining Contractual Life	2 years 9 months 4 days
Stock Options Exercisable (in shares) | shares	50,000
Weighted Average Exercise Price (in dollars per share)	$ 0.79
$1.01 - $1.50
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Exercise Price Range, Lower Range Limit (in dollars per share)	1.01
Exercise Price Range, Upper Range Limit (in dollars per share)	$ 1.50
Stock Options Outstanding (in shares) | shares	1,802,400
Weighted Average Exercise Price (in dollars per share)	$ 1.07
Weighted Average Remaining Contractual Life	4 years 10 months 13 days
Stock Options Exercisable (in shares) | shares	1,802,400
Weighted Average Exercise Price (in dollars per share)	$ 1.07
$1.51 - $10.67
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Exercise Price Range, Lower Range Limit (in dollars per share)	1.51
Exercise Price Range, Upper Range Limit (in dollars per share)	$ 10.67
Stock Options Outstanding (in shares) | shares	2,601,861
Weighted Average Exercise Price (in dollars per share)	$ 7.72
Weighted Average Remaining Contractual Life	8 years 4 months 6 days
Stock Options Exercisable (in shares) | shares	1,218,477
Weighted Average Exercise Price (in dollars per share)	$ 7.75