CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (USD $) In Thousands	9 Months Ended
	Sep. 30, 2011	Sep. 30, 2010
Cash Flows from Operating Activities:
Net Loss	$ (32,067)	$ (25,194)
Adjustments to Reconcile Net Loss to Net Cash Used in Operating Activities:
Depreciation and Amortization	1,696	2,188
Amortization of Intangible Assets	1,622	2,660
Amortization and Premium of Marketable Securities	(96)	(89)
Realized Loss on Sales and Maturities of Marketable Securities	5	22
Gain on Sale or Disposal of Assets	(58)	(11)
Stock-Based Compensation Expense	1,703	2,197
Non-Cash Interest Expense	250	546
Changes in Operating Assets and Liabilities:
Accounts and Other Receivables	120	88
Prepaid and Other Current Assets	58	(108)
Other Assets	15	554
Accounts Payable and Accrued Expenses	556	(2,141)
Deferred Revenue		(3,406)
Other Liabilities	(92)	(1,663)
Net Cash Used in Operating Activities	(26,288)	(24,357)
Cash Flows from Investing Activities:
Sales and Maturities of Marketable Securities	38,353	30,210
Purchases of Marketable Securities	(48,217)	(52,272)
Acquisition of Property and Equipment	(403)	(1,662)
Proceeds from Sale or Disposal of Assets	68	50
Net Cash Used in Investing Activities	(10,199)	(23,674)
Cash Flows from Financing Activities:
Net Proceeds from Stock Issuances	35,880	1,001
Issuance of Term Loan	5,000
Payment of Convertible Subordinated Debt	(12,503)
Payments of Other Long-Term Liabilities	(72)	(145)
Net Cash Provided by Financing Activities	28,305	856
Effect of Exchange Rate Changes on Cash and Cash Equivalents	(8)	1
Net Decrease in Cash and Cash Equivalents	(8,190)	(47,174)
Cash and Cash Equivalents at Beginning of Period	21,287	57,002
Cash and Cash Equivalents at End of Period	$ 13,097	$ 9,828