Stockholders' Equity (Allocation of Stock Option Compensation Expense) (Details) (USD $)	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014
Stock options [Member]
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Stock based compensation expense	$ 903,570	$ 1,318,784
Stock options [Member] | Cost of sales [Member]
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Stock based compensation expense	72,703	85,177
Stock options [Member] | Selling, general and administrative expenses [Member]
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Stock based compensation expense	784,078	1,212,821
Stock options [Member] | Research and development [Member]
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Stock based compensation expense	46,789	20,786
Restricted share units [Member] | Selling, general and administrative expenses [Member]
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Stock based compensation expense	652,741	674,916
Additional compensation expense due to accelerated vesting		$ 48,536