Condensed Consolidated Statements of Cash Flows - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Cash flows from operating activities:
Net income (loss)	$ 84,090	$ (59,770)
Adjustments to reconcile net income (loss) to cash flows from operating activities:
Gain from sale of Priority Review Voucher	(125,000)
Depreciation and amortization	1,637	1,397
Amortization of (discount) premium on available-for-sale securities and non-cash interest	(18)	242
Loss on abandonment of patents	485	15
Stock-based compensation	5,712	6,835
Changes in operating assets and liabilities, net:
Net increase in accounts receivable	(7,050)	(13)
Net increase in inventory	(17,632)
Net decrease (increase) in other assets	774	(3,180)
Net decrease in accounts payable, accrued expenses, deferred revenue and other liabilities	(886)	(6,214)
Net cash used in operating activities	(57,888)	(60,688)
Cash flows from investing activities:
Purchase of property and equipment	(4,465)	(1,168)
Purchase of intangible assets	(1,245)	(410)
Proceeds from sale of Priority Review Voucher	125,000
Maturity of restricted investment	10,695
Maturity of available-for-sale securities	80,000	21,000
Net cash provided by investing activities	209,985	19,422
Cash flows from financing activities:
Repayments of long-term debt and notes payable	(2,543)	(2,525)
Proceeds from exercise of options and purchase of stock under the Employee Stock Purchase Program	2,749	1,488
Net cash provided by (used in) financing activities	206	(1,037)
Increase (decrease) in cash and cash equivalents	152,303	(42,303)
Cash, cash equivalents and restricted cash:
Beginning of period	122,556	80,439
End of period	274,859	38,136
Supplemental disclosure of cash flow information:
Cash paid during the period for interest	291	409
Supplemental schedule of non-cash investing activities and financing activities:
Shares withheld for taxes	165	44
Accrual for debt issuance costs related to the senior secured term loan	400	400
Intangible assets included in accrued expenses	179	192
Property and equipment included in accrued expenses	$ 330	$ 19