Consolidated Statements of Cash Flows (USD $)	6 Months Ended
	Jun. 30, 2011	Jun. 30, 2010
Cash flows from operating activities:
Net loss	$ (17,018,451)	$ (11,090,975)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation and amortization	1,689,014	1,075,478
Interest expense relating to issuance of warrants	22,603	26,738
Loss on extinguishment of debt	7,379,465
Non-cash interest income related to preferred stock and associated warrants	(2,467,876)
Stock-based compensation	724,249	375,321
Deferred rent	(78,934)	(66,061)
Changes in operating assets and liabilities:
Accounts receivable	(410,667)	(369,812)
Unbilled costs on government contracts	(44,225)	76,775
Prepaid expenses and other current assets	79,791	61,249
Accounts payable	(1,816,857)	227,112
Accrued compensation and benefits	225,849	(332,154)
Advance billings on contracts	(22,837)	(33,122)
Accrued loss on contract commitments	(105,037)	(201,507)
Other accrued expenses and current liabilities	(1,847,572)	1,094,031
Net cash used in operating activities	(13,691,485)	(9,156,927)
Cash flows from investing activities:
Restricted cash	26,077	(7)
Increase in other assets	(37,986)	(81,812)
Purchases and manufacture of property and equipment	(14,381,566)	(2,346,585)
Advance payments to suppliers (net)	373,156	(4,681,335)
Net cash used in investing activities	(14,020,319)	(7,109,739)
Cash flows from financing activities:
Stock offerings, net of expenses	(21,729)	1,513,354
Shares issued under employee stock purchase plan	43,244	60,522
Issuance of debt	16,155,582
Repayment of debt	(347,392)	(325,509)
Cash paid for financing costs	(49,510)	(944,142)
Preferred warrant exercises	5,000,000
Common warrant exercises	1,442,633	4,765,237
Net cash provided by financing activities	22,222,828	5,069,462
(Decrease) increase in cash and cash equivalents	(5,488,976)	(11,197,204)
Cash and cash equivalents, beginning of period	10,865,760	22,605,147
Cash and cash equivalents, end of period	5,376,784	11,407,943
Supplemental disclosure of cash flow information:
Cash paid for interest	122,471	149,213
Common Stock issued in lieu of dividends or to redeem or convert mandatorily redeemable preferred stock	$ 15,153,457