CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (USD $)	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Cash flows from operating activities:
Net income (loss)	$ (14,059,539)	$ 29,099,579	$ (50,348,301)
Adjustments to reconcile net income (loss) to net cash used in operating activities
Depreciation and other amortization	419,358	568,288	625,343
Increase (decrease) in fair value of warrants	(804,516)	(24,436,309)	38,099,969
Stock based compensation	1,779,515	12,463,772	1,483,955
Changes in assets and liabilities:
Accounts receivable	(2,104,404)	365,041	(596,283)
Inventory	(17,641,922)	0	0
Deferred costs	(2,591,462)	(250,072)	0
Prepaid expenses	(444,251)	12,119	1,216,055
Other assets	(548,419)	(4,697)	24,103
Deferred income taxes, net	(7,847,802)	(36,051,978)	175,175
Accounts payable, accrued expenses and other current liabilities	7,550,989	2,659,597	(125,929)
Deferred revenue	16,050,910	41,001,110	0
Other liabilities	18,717	147,586	(1,379,471)
Net cash used in operating activities	(20,222,826)	25,574,036	(10,825,384)
Cash flows from investing activities:
Capital expenditures	(588,235)	(237,023)	(549,944)
Collateral for surety bond	(1,347,956)	0	0
Proceeds from maturity of short term investments	0	40,000,000	31,250,000
Purchases of short term investments	0	(25,004,717)	(41,235,922)
Net cash (used in) provided by investing activities	(1,936,191)	14,758,260	(10,535,866)
Cash flows from financing activities:
Net proceeds from exercise of warrants and options	9,577	3,946,237	13,196,990
Repurchase of common stock	0	(1,353,656)	0
Proceeds from issuance of long-term debt	4,910,000	0	0
Net cash provided by financing activities	4,919,577	2,592,581	13,196,990
Net increase (decrease) in cash and cash equivalents	(17,239,440)	42,924,877	(8,164,260)
Cash and cash equivalents at beginning of period	49,256,930	6,332,053	14,496,313
Cash and cash equivalents at end of period	32,017,490	49,256,930	6,332,053
Supplemental disclosure of non-cash financing activities:
Reclass of common stock warrant liability to additional paid-in capital upon warrant exercise	$ 0	$ 9,531,911	$ 30,555,845