Condensed Consolidated Statements of Cash Flows - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015
Operating Activities:
Net loss	$ (62,034)	$ (26,690)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation and amortization	745	745
Amortization of premium on marketable securities	159	681
Stock-based compensation	13,128	8,664
Change in fair value of contingent consideration liability		(1,800)
Intangible impairment		1,870
Other	54
Benefit from income taxes	(27)	(4,087)
Net changes in operating assets and liabilities:
Interest receivable	(3)	24
Accounts receivable	1,039	3,364
Prepaid expenses and other assets	(725)	129
Accounts payable and accrued liabilities	(1,919)	(2,534)
Accrued compensation and employee benefits	89	(74)
Deferred revenues	(4,087)	(4,908)
Net cash used in operating activities	(53,581)	(24,616)
Investing Activities:
Purchases of marketable securities	(188,129)	(168,627)
Maturities of marketable securities	200,497	203,175
Purchases of property and equipment	(509)	(2,327)
Net cash provided by investing activities	11,859	32,221
Financing Activities:
Taxes paid related to net share settlement of equity awards	(534)	(48)
Proceeds from issuance of common stock	760	6,248
Claims settlement under Section 16(b)		14,452
Net cash provided by financing activities	226	20,652
Net increase / (decrease) in cash and cash equivalents	(41,496)	28,257
Cash and cash equivalents, beginning of period	69,482	6,030
Cash and cash equivalents, end of period	27,986	$ 34,287
Supplemental disclosure of noncash investing activities:
Property and equipment included in accrued liabilities	$ 2,202