Stock Option Plans (Schedule of Options Outstanding) (Details)	12 Months Ended
	Dec. 31, 2014
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Options Outstanding Number of Options	2,833,604
Options Outstanding Weighted Average Remaining Contractual Term	7 years 10 months 24 days
Options Exercisable Number of Options	1,498,929
Options Exercisable Weighted Average Remaining Contractual Term	6 years 10 months 24 days
$ 0.67 to 0.99 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Options Outstanding Number of Options	730,771
Options Outstanding Weighted Average Remaining Contractual Term	9 years 6 months
Options Exercisable Number of Options	68,635
Options Exercisable Weighted Average Remaining Contractual Term	9 years 6 months
$ 1.00 to 1.99 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Options Outstanding Number of Options	1,597,331
Options Outstanding Weighted Average Remaining Contractual Term	8 years 1 month 6 days
Options Exercisable Number of Options	956,875
Options Exercisable Weighted Average Remaining Contractual Term	7 years 9 months 18 days
$ 2.00 to 2.99 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Options Outstanding Number of Options	288,002
Options Outstanding Weighted Average Remaining Contractual Term	6 years 7 months 6 days
Options Exercisable Number of Options	255,919
Options Exercisable Weighted Average Remaining Contractual Term	6 years 6 months
$ 3.00 to 3.99 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Options Outstanding Number of Options	71,000
Options Outstanding Weighted Average Remaining Contractual Term	3 years 7 months 6 days
Options Exercisable Number of Options	71,000
Options Exercisable Weighted Average Remaining Contractual Term	3 years 7 months 6 days
$ 4.29 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Options Outstanding Number of Options	11,500
Options Outstanding Weighted Average Remaining Contractual Term	2 years 7 months 6 days
Options Exercisable Number of Options	11,500
Options Exercisable Weighted Average Remaining Contractual Term	2 years 7 months 6 days
$ 7 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Options Outstanding Number of Options	135,000
Options Outstanding Weighted Average Remaining Contractual Term	2 years 4 months 24 days
Options Exercisable Number of Options	135,000
Options Exercisable Weighted Average Remaining Contractual Term	2 years 4 months 24 days