Fair Value of Financial Instruments (Tables)

6 Months Ended

12 Months Ended

Jun. 30, 2013

Dec. 31, 2012

Fair Value Disclosures [Abstract]

Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis [Table Text Block]

	Level 1			Level 2			Level 3			Total
June 30, 2013
Financial Assets:
Cash and cash equivalents		$	3,035,998		$	—		$	—		$	3,035,998
Total assets		$	3,035,998		$	—		$	—		$	3,035,998
Financial Liabilities:
Warrant derivative liabilities		$	—		$	—		$	701,857		$	701,857
Conversion element of promissory notes			—			—			439			439
Conversion element of Series B CPS			—			—			1,213,727			1,213,727
Series A CPS derivative liabilities			—			—			770,641			770,641
Total liabilities		$	—		$	—		$	2,686,664		$	2,686,664

	Level 1			Level 2			Level 3			Total
December 31, 2012
Financial Assets:
Cash and cash equivalents		$	6,328,753		$	—		$	—		$	6,328,753
Total assets		$	6,328,753		$	—		$	—		$	6,328,753
Financial Liabilities:
Warrant derivative liabilities		$	—		$	—		$	102,695		$	102,695
Conversion element of promissory notes			—			—			274,928			274,928
Conversion element of Series B CPS			—			—			1,210,909			1,210,909
Series A CPS derivative liabilities			—			—			619,652			619,652
Total liabilities		$	—		$	—		$	2,208,184		$	2,208,184

	Level 1		Level 2		Level 3		Total
December 31, 2012
Financial Assets:
Cash and cash equivalents	$	6,328,753	$	—	$	—	$	6,328,753
Total assets	$	6,328,753	$	—	$	—	$	6,328,753
Financial Liabilities:
Warrant derivative liabilities	$	—	$	—	$	102,695	$	102,695
Conversion element of promissory notes		—		—		274,928		274,928
Conversion element of Series B CPS		—		—		1,210,909		1,210,909
Series A CPS derivative liabilities		—		—		619,652		619,652
Total liabilities	$	—	$	—	$	2,208,184	$	2,208,184

	Level 1		Level 2		Level 3		Total
December 31, 2011
Financial Assets:
Cash and cash equivalents	$	15,117,172	$	—	$	—	$	15,117,172
Total assets	$	15,117,172	$	—	$	—	$	15,117,172
Financial Liabilities:
Warrant derivative liabilities	$	—	$	—	$	655,219	$	655,219
Conversion element of promissory notes		—		—		1,931,295		1,931,295
Conversion element of Series B CPS		—		—		1,245,101		1,245,101
Series A CPS derivative liabilities		—		—		2,135,715		2,135,715
Total liabilities	$	—	$	—	$	5,967,330	$	5,967,330

Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Table Text Block]

				Conversion
					Element of			Conversion
	Warrant				Promissory			Element of			Series A CPS
	Derivatives				Notes			Series B CPS			Derivatives			Total
Balance at January 1, 2013	$	102,695			$	274,928		$	1,210,909		$	619,652		$	2,208,184
Issuances		—				—			—			—			—
Revaluation (gains) losses included in other income and (expenses)		599,162				(274,489	)		2,818			150,989			478,480
Settlements		—				—			—			—			—
Balance at June 30, 2013	$	701,857			$	439		$	1,213,727		$	770,641		$	2,686,664
Total gains (losses) included in other income and (expenses) attributable to liabilities still held as of June 30, 2013	$	(599,163	)		$	274,489		$	(2,818	)	$	(150,989	)	$	(478,481	)

				Conversion
					Element of			Conversion
	Warrant				Promissory			Element of			Series A CPS
	Derivatives				Notes			Series B CPS			Derivatives			Total
Balance at January 1, 2012	$	655,219			$	1,931,295		$	1,245,101		$	2,135,715		$	5,967,330
Issuances		—				—			—			—			—
Revaluation (gains) losses included in other income and (expenses)		(325,805	)			(1,529,374	)		82,668			(789,680	)		(2,562,191	)
Settlements		—				—			—			—			—
Balance at June 30, 2012	$	329,414			$	401,921		$	1,327,769		$	1,346,035		$	3,405,139
Total gains (losses) included in other income and (expenses) attributable to liabilities still held as of June 30, 2012	$	325,805			$	1,529,374		$	(82,668	)	$	789,680		$	2,562,191

				Conversion
				Element of			Conversion
	Warrant			Promissory			Element of			Series A CPS
	Derivatives			Notes			Series B CPS			Derivatives			Total
Balance at January 1, 2012	$	655,219		$	1,931,295		$	1,245,101		$	2,135,715		$	5,967,330
Issuances		—			—			—			—			—
Revaluation (gains) losses included in other income and expenses		(552,524	)		(1,656,367	)		(34,192	)		(1,516,063	)		(3,759,146	)
Settlements		—			—			—			—			—
Balance at December 31, 2012	$	102,695		$	274,928		$	1,210,909		$	619,652		$	2,208,184
Total gains (losses) included in other income and expenses attributable to liabilities still held as of December 31, 2012	$	552,524		$	1,656,367		$	34,192		$	1,516,063		$	3,759,146

				Conversion
				Element of			Conversion
	Warrant			Promissory			Element of			Series A CPS
	Derivatives			Notes			Series B CPS			Derivatives			Total
Balance at January 1, 2011	$	2,240,962		$	—		$	194,088		$	—		$	2,435,050
Issuances		—			11,495,163			—			2,198,828			13,693,991
Revaluation (gains) losses included in other income and expenses		(1,269,940	)		(8,989,945	)		1,051,013			(63,113	)		(9,271,985	)
Settlements		(315,803	)		(573,923	)		—			—			(889,726	)
Balance at December 31, 2011	$	655,219		$	1,931,295		$	1,245,101		$	2,135,715		$	5,967,330
Total gains (losses) included in other income and expenses attributable to liabilities still held as of December 31, 2011	$	1,324,165		$	8,989,945		$	(1,051,013	)	$	63,113		$	9,326,210