Nature of Operations (Narrative) (Details) (USD $)	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Liquidity Disclosure [Line Items]
Net Loss	$ 15,895,372	$ 10,325,464	$ 33,792,515	$ 23,388,120	$ 31,900,000	$ 27,500,000	$ 47,000,000
Accumulated deficit	820,507,992		820,507,992		786,646,266
Expected operating cash burn for fiscal year 2013			20,000,000
Net Cash Provided By Used In Operating Activities Continuing Operations			17,944,745	15,548,189
Cash and cash equivalents	10,959,955	9,461,404	10,959,955	9,461,404	9,380,059	13,856,893
Net working capital	$ 14,600,000		$ 14,600,000		$ 6,900,000