Condensed Consolidated Statements of Cash Flows (Unaudited) (USD $) In Thousands	9 Months Ended
	Sep. 30, 2011	Sep. 30, 2010
Cash flows from operating activities:
Net loss	$ (33,854)	$ (45,398)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation and amortization	3,036	3,688
Share-based compensation expense	1,843	2,892
Revenue adjustment for contingently issuable shares	(17)	199
Other	164	118
Changes in operating assets and liabilities:
Receivables from related party	(321)	(20)
Other assets	(2,354)	(986)
Accounts payable	(882)	113
Accrued expenses and other current liabilities	(4,130)	2,249
Deferred revenue	(1,967)	5,111
Deferred revenue, related party	(2,343)	(3,606)
Other liabilities	(780)	(1,401)
Net cash used in operating activities	(41,605)	(37,041)
Cash flows from investing activities:
Purchases of property and equipment	(752)	(549)
Sales of marketable security		1,476
Net cash provided by (used in) investing activities	(752)	927
Cash flows from financing activities:
Proceeds from exercise of common stock options	685	228
Proceeds from issuance of common stock to related party	5,056	99
Proceeds from issuance of common stock, net of offering costs	55,169	26,266
Net cash provided by financing activities	60,910	26,593
Effect of changes in exchange rates on cash and cash equivalents	25	22
Net increase (decrease) in cash and cash equivalents	18,578	(9,499)
Cash and cash equivalents at beginning of period	46,115	46,519
Cash and cash equivalents at end of period	64,693	37,020
Supplemental disclosure of cash flow information:
Change in value of shares of common stock contingently issuable or issued to related party	$ (120)	$ 297