Stock-Based Compensation (Details Textual) (USD $)				6 Months Ended		3 Months Ended		6 Months Ended		12 Months Ended		6 Months Ended	12 Months Ended		6 Months Ended
	Jun. 30, 2013	Dec. 31, 2012	Dec. 31, 2011	Jun. 30, 2013 Employees And Directors [Member]	Jun. 30, 2012 Employees And Consultants [Member]	Jun. 30, 2013 Employees And Consultants [Member] General and Administrative Expenses and Research and Development Expense [Member]	Jun. 30, 2012 Employees And Consultants [Member] General and Administrative Expenses and Research and Development Expense [Member]	Jun. 30, 2013 Employees And Consultants [Member] General and Administrative Expenses and Research and Development Expense [Member]	Jun. 30, 2012 Employees And Consultants [Member] General and Administrative Expenses and Research and Development Expense [Member]	Dec. 31, 2001 2001 Stock Plan [Member]	Jun. 30, 2013 2001 Stock Plan [Member]	Jun. 30, 2013 2007 Stock Plan [Member]	Dec. 31, 2007 2007 Stock Plan [Member]	Mar. 20, 2007 2007 Stock Plan [Member]	Jun. 30, 2013 2010 Stock Plan [Member]	Nov. 02, 2010 2010 Stock Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number	3,860,136	4,453,746	2,979,010								953,507			2,500,000	2,463,056	3,000,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross				117,500	1,550,000					250,000		443,573	250,000		2,463,056
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Fair Value				$ 185,000	$ 3,500,000
Allocated Share-based Compensation Expense						407,000	400,000	864,000	908,000
Employee Service Share-based Compensation, Nonvested Awards, Total Compensation Cost Not yet Recognized, Stock Options	$ 2,200,000