Stock-Based Compensation (Details 1) - Stock Option [Member] - USD ($)	6 Months Ended	12 Months Ended
	Jun. 30, 2016	Dec. 31, 2015	Dec. 31, 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options, Beginning Balance	8,941,930	5,981,106
Options, Granted	560,000	3,781,666
Options, Exercised	(442,834)	(35,008)
Options, Expired	(249,502)	(483,332)
Options, Forfeited	(196,181)	(302,502)
Options, Ending Balance	8,613,413	8,941,930	5,981,106
Options, Exercisable	5,048,957
Weighted Average Exercise Price, Beginning Balance	$ 2.14	$ 2.01
Weighted Average Exercise Price, Granted	2.01	2.37
Weighted Average Exercise Price, Exercised	1.83	1.16
Weighted Average Exercise Price, Expired	1.93	2.48
Weighted Average Exercise Price, Forfeited	2.34	1.91
Weighted Average Exercise Price, Ending Balance	2.15	$ 2.14	$ 2.01
Weighted Average Exercise Price, Exercisable	$ 2.01
Weighted Average Remaining Contractual Life, Balance Outstanding	5 years 5 months 1 day	5 years 9 months 18 days	5 years 9 months 18 days
Weighted Average Remaining Contractual Life, Exercisable	4 years 6 months 29 days
Aggregate Intrinsic Value, Beginning Balance	$ 2,900,000	$ 685,000
Aggregate Intrinsic Value, Exercised	136,913	44,000
Aggregate Intrinsic Value, Ending Balance	1,316,398	2,900,000	$ 685,000
Aggregate Intrinsic Value, Exercisable	1,136,604
Grant date fair value of options granted	$ 962,000	$ 7,974,000
Weighted average grant date fair value	$ 1.72	$ 2.12