Summary of Significant Accounting Policies (Tables)

12 Months Ended

Dec. 31, 2012

Summary of Significant Accounting Policies [Abstract]

Estimated Useful Life of Property and Equipment

	Estimated Useful Life
Asset Category	(in Years)
Leasehold improvements	8- 10
Furniture and office equipment	5
Computer and other equipment	3- 5

Schedule of Share-based Compensation Expense

	Year ended December 31,
	2012		2011		2010
Research and development	$	518,375	$	754,554	$	1,008,368
General and administrative		1,375,724		1,811,407		1,504,791
Total share-based compensation expense	$	1,894,099	$	2,565,961	$	2,513,159