Stock-Based Compensation (Details 2) - $ / shares	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Range of Exercise Price 0.09-2.00 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options Outstanding, Range of Exercise Price Lower	$ 0.09	$ 0.09	$ 0.09
Options Outstanding, Range of Exercise Price Upper	$ 2.00	$ 2.00	$ 2.00
Options Outstanding, Options	3,029,938	2,703,280	2,093,196
Options Outstanding, Weighted Average Exercise Price	$ 1.40	$ 1.37	$ 1.29
Options Outstanding, Weighted Average Remaining Contractual Life	4 years 1 month 13 days	4 years 3 months 29 days	4 years 8 months 23 days
Options Exercisable, Options	2,363,683	2,018,074	1,901,737
Options Exercisable, Weighted Average Exercise Price	$ 1.34	$ 1.28	$ 1.25
Options Exercisable, Weighted Average Remaining Contractual Life	3 years 4 months 17 days	3 years 8 months 23 days	4 years 7 months 20 days
Range of Exercise Price 2.01-3.00 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options Outstanding, Range of Exercise Price Lower	$ 2.01	$ 2.01	$ 2.01
Options Outstanding, Range of Exercise Price Upper	$ 3.00	$ 3.00	$ 3.00
Options Outstanding, Options	5,866,168	3,232,002	1,770,560
Options Outstanding, Weighted Average Exercise Price	$ 2.50	$ 2.49	$ 2.28
Options Outstanding, Weighted Average Remaining Contractual Life	6 years 6 months	7 years 29 days	6 years 7 months 24 days
Options Exercisable, Options	2,348,247	1,829,298	1,205,976
Options Exercisable, Weighted Average Exercise Price	$ 2.44	$ 2.40	$ 2.26
Options Exercisable, Weighted Average Remaining Contractual Life	5 years 9 months 4 days	6 years 8 months 23 days	6 years 3 months
Range of Exercise Price 3.01-6.00 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options Outstanding, Range of Exercise Price Lower	$ 3.01	$ 3.01	$ 3.01
Options Outstanding, Range of Exercise Price Upper	$ 6.00	$ 6.00	$ 6.00
Options Outstanding, Options	45,824	45,824	45,824
Options Outstanding, Weighted Average Exercise Price	$ 5.24	$ 5.24	$ 5.24
Options Outstanding, Weighted Average Remaining Contractual Life	1 year 7 months 13 days	2 years 7 months 13 days	3 years 7 months 13 days
Options Exercisable, Options	45,824	45,824	45,824
Options Exercisable, Weighted Average Exercise Price	$ 5.24	$ 5.24	$ 5.24
Options Exercisable, Weighted Average Remaining Contractual Life	1 year 7 months 13 days	2 years 7 months 13 days	3 years 7 months 13 days
Range of Exercise Price 0.09-6.00 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options Outstanding, Range of Exercise Price Lower	$ 0.09	$ 0.09	$ 0.09
Options Outstanding, Range of Exercise Price Upper	$ 6.00	$ 6.00	$ 6.00
Options Outstanding, Options	8,941,930	5,981,106	3,909,580
Options Outstanding, Weighted Average Exercise Price	$ 2.14	$ 2.01	$ 1.78
Options Outstanding, Weighted Average Remaining Contractual Life	5 years 8 months 1 day	5 years 9 months 18 days	5 years 7 months 2 days
Options Exercisable, Options	4,757,754	3,893,196	3,153,537
Options Exercisable, Weighted Average Exercise Price	$ 1.92	$ 1.85	$ 1.69
Options Exercisable, Weighted Average Remaining Contractual Life	4 years 6 months 14 days	5 years 1 month 13 days	5 years 2 months 26 days