Statements Of Cash Flows (USD $) In Thousands, unless otherwise specified	12 Months Ended			377 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009	Dec. 31, 2011
Cash flows from operating activities:
Net income (loss)	$ (2,318)	$ (32,177)	$ (25,159)	$ (309,964)
Adjustments to reconcile net loss to net cash flows used in operating activities:
Depreciation and amortization	1,300	1,463	1,379	20,445
Loss on disposal of assets	190	776	347	2,271
Realized gain on sale of short-term securities-available-for-sale				(3,863)
Write-down of short-term securities-available-for-sale				17,001
Impairment charge on real estate owned	109	408	128	1,445
Stock-based compensation	3,129	3,169	2,374	28,995
Conversion of interest accrued to common stock				8
Acquired in-process research and development				29,461
Increase (decrease) on warrant valuation	(33,022)	11,502	9,198	(24,970)
(Increase) decrease in:
Accounts receivable and other current assets	(1,063)	(1,211)	2,621	(5,174)
Net increase in accounts payable, accrued employee compensation, and other liabilities	7,996	861	312	14,131
Net cash used in operating activities	(23,679)	(15,209)	(8,800)	(230,214)
Cash flows from investing activities:
Purchase of property and equipment	(1,178)	(832)	(931)	(19,879)
Patent costs	(1,127)	(1,122)	(1,063)	(9,492)
Purchase of marketable securities		(7)		(112,993)
Sale of marketable securities			111	117,724
Acquisition costs				(2,389)
Net cash used in investing activities	(2,305)	(1,961)	(1,883)	(27,029)
Cash flows from financing activities:
Proceeds from sale of common stock, warrants, and partnership units, net of offering costs, and exercise of options and warrants	32,380	2,561	47,840	297,878
Repayments of long-term debt	(81)	(77)	(74)	(345)
Buyback of common stock pursuant to rescission offering				(289)
Withdrawal of partnership net assets				(177)
Issuance of convertible debt				80
Net cash provided by financing activities	32,299	2,484	47,766	297,147
Increase (decrease) in cash and cash equivalents	6,315	(14,686)	37,083	39,904
Cash and cash equivalents:
Beginning of period	33,589	48,275	11,192
End of period	39,904	33,589	48,275	39,904
SUPPLEMENTAL DISCLOSURE OF CASH FLOW INFORMATION:
Cash paid during the year for interest	90	94	97	489
SUPPLEMENTAL SCHEDULE OF NONCASH INVESTING ACTIVITIES AND FINANCING ACTIVITIES:
Short-term securities-available-for-sale received in connection with the private offering				17,897
Change in unrealized gain (loss) on short-term securities-available-for-sale
Issuance of common stock and warrants in satisfaction of liabilities	643			1,188
Issuance of common stock for building purchase				750
Assumption of long-term debt for building purchase				2,200
Issuance of common stock to acquire assets				8,075
Assumption of liabilities to acquire assets				$ 2,124