Condensed Consolidated Statements of Cash Flows - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015
Cash flows from operating activities
Net loss	$ (89,616)	$ (57,334)
Adjustments to reconcile net loss to net cash used in operating activities
Non-cash interest expense	3,505	4,038
Non-cash loss on extinguishment of convertible notes due 2020	14,566
Loss on disposal of property and equipment	227
Depreciation and amortization expense	3,020	2,092
Stock-based compensation expense	7,891	8,337
Changes in operating assets and liabilities:
Accounts receivable	(12,842)	1,711
Inventory	(8,384)
Accounts payable, accrued expenses and other	(7,072)	7,474
Deferred revenues	(17,277)	(26,502)
Other assets and liabilities, net	1,556	527
Net cash used in operating activities	(104,426)	(59,657)
Cash flows from investing activities
Purchases of marketable securities	(84,262)
Proceeds from sales and maturities of marketable securities	23,000	53,963
Purchases of property and equipment	(2,050)	(4,105)
Net cash (used in) provided by investing activities	(63,312)	49,858
Cash flows from financing activities
Proceeds from exercise of options and warrants to purchase common stock	2,598	6,542
Proceeds from issuance of convertible promissory notes by Silver Creek Pharmaceuticals, Inc.	1,025
Proceeds from issuance of preferred stock by Silver Creek Pharmaceuticals, Inc.		1,233
Net cash provided by financing activities	3,623	7,775
Net decrease in cash and cash equivalents	(164,115)	(2,024)
Cash and cash equivalents, beginning of period	185,606	35,688
Cash and cash equivalents, end of period	21,491	33,664
Non-cash investing and financing activities
Purchases of property and equipment in accounts payable, accrued expenses and other	434	2,060
Receivables related to stock option exercises in prepaid expenses and other current assets	13	160
Principal amount of convertible notes due 2020 converted into shares of common stock	64,209
Transaction costs related to conversion of convertible notes due 2020 in accounts payable, accrued expenses and other	169
Supplemental disclosure of cash flows
Cash paid for interest	$ 12,484	$ 4,946