Condensed Consolidated Statements of Cash Flows (USD $) In Thousands, unless otherwise specified	9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012
Statement of Cash Flows [Abstract]
Net loss	$ (12,655)	$ (29,256)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation and amortization	1,787	1,651
Stock-based compensation	6,046	3,522
Change in fair value of contingent consideration related to acquisition	5,200	12,700
Research and Development in Process	752	0
Changes in operating assets and liabilities:
Accounts receivable	(968)	(4,074)
Inventories	93	(957)
Prepaid expenses and other current assets	(622)	(479)
Accounts payable	(1,125)	(1,983)
Accrued payroll	2,351	407
Accrued expenses and other current liabilities	637	1,262
Settlement cost	100	(8)
Settlement cost	0	5,000
Net cash provided by (used in) operating activities	1,596	(12,215)
Investing activities:
Purchases of property and equipment	(1,620)	(1,408)
Purchase of patent license	0	(100)
Business acquisition	0	(2,367)
Net cash used in investing activities	(1,620)	(3,875)
Net cash used in investing activities
Proceeds from sale of stock, net of expenses	0	40,069
Proceeds from sale of common stock under employee stock purchase plan	1,646	1,409
Proceeds from exercise of stock options	3,160	2,355
Funding of restricted cash account	(5,395)	0
Release of restricted cash account	(5,395)	0
Net cash provided by financing activities	4,806	43,833
Effect of exchange rate changes on cash and cash equivalents	(414)	(38)
Net increase in cash and cash equivalents	4,368	27,705
Cash and cash equivalents, beginning of period	45,118	20,035
Cash and cash equivalents, end of period	$ 49,486	$ 47,740