Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Cash flows from operating activities:
Net loss	$ (34,883)	$ (28,076)
Adjustments to reconcile consolidated net loss to net cash used in operating activities:
Depreciation and amortization	521	355
Increase in fair value of Symphony Icon, Inc. purchase liability	965	1,753
Stock-based compensation	1,835	1,953
Amortization of debt issuance costs	125	62
Loss on disposal of property and equipment	12	6
Changes in operating assets and liabilities:
Decrease in accounts receivable	170	865
(Increase) decrease in prepaid expenses and other current assets	(4,134)	1,570
Increase in other assets	0	(393)
Increase (decrease) in accounts payable and other liabilities	3,836	(1,302)
Decrease in deferred revenue	(12,187)	(278)
Net cash used in operating activities	(43,740)	(23,485)
Cash flows from investing activities:
Purchases of property and equipment	(54)	(17)
Proceeds from disposal of property and equipment	0	4
Purchases of investments	(208,986)	(70,978)
Maturities of investments	75,400	0
Net cash used in investing activities	(133,640)	(70,991)
Cash flows from financing activities:
Proceeds from issuance of common stock	184	0
Repurchase of common stock	(621)	(357)
Repayment of debt borrowings	(491)	(456)
Other financing activities	0	(17)
Net cash used in financing activities	(928)	(830)
Net decrease in cash and cash equivalents	(178,308)	(95,306)
Cash and cash equivalents at beginning of period	202,989	137,266
Cash and cash equivalents at end of period	24,681	41,960
Supplemental disclosure of cash flow information:
Cash paid for interest	378	412
Supplemental disclosure of non-cash investing and financing activities:
Unrealized gain on investments	$ 516	$ 86