Condensed Consolidated Balance Sheets - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016
Current assets:
Cash and cash equivalents	$ 521,265	$ 785,877
Accounts receivable	27,680	6,195
Inventories	50,527	14,700
Other current assets	22,257	10,515
Total current assets	621,729	817,287
Intangible assets, net	43,155	12,877
Property and equipment, net	9,877	6,640
Restricted cash	2,521	1,694
Other assets	8,436	3,795
Total assets	685,718	842,293
Current liabilities:
Accounts payable	5,984	5,236
Accrued expenses	123,076	68,700
Deferred revenue, current	95	95
Other current liabilities	2,287	2,978
Total current liabilities	131,442	77,009
Convertible notes, net	140,362	131,775
Deferred revenue, non-current	235	305
Other non-current liabilities	6,318	5,086
Total liabilities	278,357	214,175
Commitments and contingencies (Note 10)
Stockholders' equity:
Preferred stock, $0.0001 par value; 10,000,000 shares authorized at both December 31, 2016 and September 30, 2017; no shares issued or outstanding at both December 31, 2016 and September 30, 2017
Common stock, $0.0001 par value; 100,000,000 shares authorized at both December 31, 2016 and September 30, 2017; 53,621,679 and 54,365,390 shares issued and outstanding at December 31, 2016 and September 30, 2017, respectively	5	5
Additional paid-in capital	1,697,544	1,604,798
Accumulated other comprehensive loss	(2,366)	(2,924)
Accumulated deficit	(1,287,822)	(973,761)
Total stockholders' equity	407,361	628,118
Total liabilities and stockholders' equity	$ 685,718	$ 842,293