Stockholders' Equity (Narrative) (Details) (USD $)	3 Months Ended
	Mar. 31, 2015	Dec. 31, 2014
Stockholders' Equity [Abstract]
Convertible preferred stock, shares outstanding	73,332	73,332
Number of common stock shares issuable for preferred stock	123,114
Additional shares issuable	49,782
Shares issued during the period	391,787
Amount received upon the exercise of stock purchase warrants and options	$ 1,885,630
Shares of common stock issued in connection with the vesting of restricted common stock	14,159
Shares of restricted common stock vested	21,350
Shares of common stock issued upon the exercise of stock purchase warrants and options	377,628
Shares issued for options	50,695
Intrinsic value of options exercised	409,402
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares authorized	6,000,000
Shares available for grant	1,805,895
Granted	553,390
Weighted average fair value per share of options granted	$ 3.81
Stock options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expiration period	10 years
Restricted share units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation cost	2,516,096
Remaining weighted average vesting period	9 months
Shares withheld in satisfaction of employee tax withholding obligations	7,191
Fair value of shares withheld in satisfaction of employee tax withholding obligations	67,409
Service based options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted	395,390
Unrecognized compensation cost	2,311,012
Remaining weighted average vesting period	2 years 3 months 18 days
Performance based options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted	158,000
Unrecognized compensation cost	$ 459,810
Remaining weighted average vesting period	9 months 4 days