Condensed Consolidated Balance Sheets - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016
Current assets:
Cash and cash equivalents	$ 507,941	$ 785,877
Accounts receivable	23,149	6,195
Inventories	28,285	14,700
Other current assets	23,045	10,515
Total current assets	582,420	817,287
Intangible assets, net	44,408	12,877
Property and equipment, net	9,958	6,640
Restricted cash	2,522	1,694
Other assets	6,087	3,795
Total assets	645,395	842,293
Current liabilities:
Accounts payable	45	5,236
Accrued expenses	99,589	68,700
Deferred revenue, current	95	95
Other current liabilities	2,701	2,978
Total current liabilities	102,430	77,009
Convertible notes, net	137,447	131,775
Deferred revenue, non-current	258	305
Other non-current liabilities	5,346	5,086
Total liabilities	245,481	214,175
Commitments and contingencies (Note 10)
Stockholders' equity:
Preferred stock, $0.0001 par value; 10,000,000 shares authorized at both December 31, 2015 and June 30, 2016; no shares issued or outstanding at both December 31, 2015 and June 30, 2016
Common stock, $0.0001 par value; 100,000,000 shares authorized at both December 31, 2015 and September 30, 2016; 40,279,783 and 51,656,692 shares issued and outstanding at December 31, 2015 and September 30, 2016, respectively	5	5
Additional paid-in capital	1,664,997	1,604,798
Accumulated other comprehensive loss	(2,543)	(2,924)
Accumulated deficit	(1,262,545)	(973,761)
Total stockholders' equity	399,914	628,118
Total liabilities and stockholders' equity	$ 645,395	$ 842,293