CONSOLIDATED STATEMENTS OF SHAREHOLDERS' EQUITY AND COMPREHENSIVE INCOME (LOSS) (USD $)	Series A Nonconvertible Preferred Stock [Member]	Common Stock [Member]	Additional Paid-in Capital [Member]	Accumulated Deficit [Member]	Accumulated Other Comprehensive Income (Loss) [Member]	Total
BALANCE at Dec. 31, 2008	$ 2,000	$ 361,320	$ 256,696,849	$ (180,472,203)	$ 126,497	$ 76,714,463
BALANCE (in shares) at Dec. 31, 2008	200,000	36,131,981
Increase (Decrease) in Shareholders' Equity [Roll Forward]
Net (loss) income				(20,505,320)		(20,505,320)
Other comprehensive (loss) income:
Unrealized loss on available-for-sale securities					(100,980)	(100,980)
Comprehensive income (loss)						(20,606,300)
Cumulative effect of the adoption of revisions, see Note 2 (Accounting Standards Codification 815 [Member])			(6,557,928)	3,868,818		(2,689,110)
Exercise of common stock options and warrants, net of tendered shares		3,403	1,698,735			1,702,138
Exercise of common stock options and warrants, net of tendered shares (in shares)		340,279
Stock-based employee compensation, net of shares withheld for employee taxes		1,471	2,446,034			2,447,505
Stock-based employee compensation, net of shares withheld for employee taxes (in shares)		147,078
Stock-based non-employee compensation		4	7,007			7,011
Stock-based non-employee compensation (in shares)		450
Issuance of common stock to Board of Directors and Scientific Advisory Board		617	750,298			750,915
Issuance of common stock to Board of Directors and Scientific Advisory Board (in shares)		61,742
Issuance of common stock in connection with materials and license agreements		1,228	1,169,492			1,170,720
Issuance of common stock in connection with materials and license agreements (in shares)		122,854
Issuance of common stock to employees under an Employee Stock Purchase Plan (ESPP)		141	130,043			130,184
Issuance of common stock to employees under an Employee Stock Purchase Plan (ESPP) (in shares)		14,056
BALANCE at Dec. 31, 2009	2,000	368,184	256,340,530	(197,108,705)	25,517	59,627,526
BALANCE (in shares) at Dec. 31, 2009	200,000	36,818,440
Increase (Decrease) in Shareholders' Equity [Roll Forward]
Net (loss) income				(19,917,410)		(19,917,410)
Other comprehensive (loss) income:
Unrealized loss on available-for-sale securities					(11,819)	(11,819)
Initial prior service cost for retirement plan					(5,611,079)	(5,611,079)
Amortization of prior service cost for retirement plan					438,366	438,366
Actuarial loss on retirement plan					(878,944)	(878,944)
Comprehensive income (loss)						(25,980,886)
Exercise of common stock options and warrants, net of tendered shares		13,047	17,742,998			17,756,045
Exercise of common stock options and warrants, net of tendered shares (in shares)		1,304,654
Stock-based employee compensation, net of shares withheld for employee taxes		6,514	3,125,844			3,132,358
Stock-based employee compensation, net of shares withheld for employee taxes (in shares)		651,384
Stock-based non-employee compensation		5	47,217			47,222
Stock-based non-employee compensation (in shares)		491
Issuance of common stock to Board of Directors and Scientific Advisory Board		619	1,346,331			1,346,950
Issuance of common stock to Board of Directors and Scientific Advisory Board (in shares)		61,946
Issuance of common stock in connection with materials and license agreements		801	1,253,819			1,254,620
Issuance of common stock in connection with materials and license agreements (in shares)		80,073
Issuance of common stock to employees under an Employee Stock Purchase Plan (ESPP)		196	245,488			245,684
Issuance of common stock to employees under an Employee Stock Purchase Plan (ESPP) (in shares)		19,583
BALANCE at Dec. 31, 2010	2,000	389,366	280,102,227	(217,026,115)	(6,037,959)	57,429,519
BALANCE (in shares) at Dec. 31, 2010	200,000	38,936,571
Increase (Decrease) in Shareholders' Equity [Roll Forward]
Net (loss) income				3,155,153		3,155,153
Other comprehensive (loss) income:
Unrealized loss on available-for-sale securities					(886)	(886)
Amortization of prior service cost and actuarial loss for retirement plan					599,999	599,999
Actuarial loss on retirement plan					(418,461)	(418,461)
Comprehensive income (loss)						3,335,805
Exercise of common stock options and warrants, net of tendered shares		12,662	27,742,456			27,755,118
Exercise of common stock options and warrants, net of tendered shares (in shares)		1,266,191
Stock-based employee compensation, net of shares withheld for employee taxes		1,031	2,105,297			2,106,328
Stock-based employee compensation, net of shares withheld for employee taxes (in shares)		103,112
Stock-based non-employee compensation		2	6,323			6,325
Stock-based non-employee compensation (in shares)		174
Issuance of common stock to Board of Directors and Scientific Advisory Board		465	1,648,303			1,648,768
Issuance of common stock to Board of Directors and Scientific Advisory Board (in shares)		46,536
Issuance of common stock in connection with materials and license agreements		2	9,179			9,181
Issuance of common stock in connection with materials and license agreements (in shares)		181
Issuance of common stock to employees under an Employee Stock Purchase Plan (ESPP)		105	307,237			307,342
Issuance of common stock to employees under an Employee Stock Purchase Plan (ESPP) (in shares)		10,531
Issuance of common stock through a public offering, net of expenses of $14,871,186		57,500	249,571,314			249,628,814
Issuance of common stock through a public offering, net of expenses of $14,871,186 (in shares)		5,750,000
BALANCE at Dec. 31, 2011	$ 2,000	$ 461,133	$ 561,492,336	$ (213,870,962)	$ (5,857,307)	$ 342,227,200
BALANCE (in shares) at Dec. 31, 2011	200,000	46,113,296