Summary of Significant Accounting Policies (Fair Value of Financial Instruments) (Details) (USD $)	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2011	Sep. 30, 2011	Jun. 30, 2011	Mar. 31, 2011
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Common stock warrants, current	$ 333,793				$ 125,841
Common stock warrants, noncurrent	657,246	1,788,682	1,789,716	2,380,660	1,412,304	2,402,720	13,791,303	21,278,533
Term loan	5,000,000
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Common stock warrants, current	333,793				125,841
Common stock warrants, noncurrent	657,246				1,412,304
Common stock warrants, current and noncurrent	$ 991,039				$ 1,538,145