Condensed Consolidated Balance Sheets - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Current assets:
Cash and cash equivalents	$ 724,829	$ 370,829
Short-term investments	324,063	803,083
Accounts receivable	68,032	49,044
Inventory	166,360	125,445
Other current assets	79,015	77,782
Total current assets	1,362,299	1,426,183
Property and equipment, net of accumulated depreciation of $44,701 and $28,149 as of September 30, 2019, and December 31, 2018, respectively	119,532	97,024
Intangible assets, net of accumulated amortization of $5,091 and $3,852 as of September 30, 2019, and December 31, 2018, respectively	11,975	11,574
Right of use asset, net	39,493
Other assets	169,171	107,294
Total assets	1,702,470	1,642,075
Current liabilities:
Accounts payable	81,946	33,829
Accrued expenses	121,663	134,095
Deferred revenue	3,303	3,303
Other current liabilities	8,944	2,463
Total current liabilities	215,856	173,690
Long-term debt	436,421	420,554
Lease liabilities	49,741
Deferred rent and other	5,248	15,555
Total liabilities	707,266	609,799
Commitments and contingencies (Note 14)
Stockholders’ equity:
Preferred stock, $0.0001 par value, 3,333,333 shares authorized; none issued and outstanding
Common stock, $0.0001 par value, 99,000,000 shares authorized; 74,504,835 and 71,071,887 issued and outstanding at September 30, 2019, and December 31, 2018, respectively	7	7
Additional paid-in capital	3,053,420	2,611,294
Accumulated other comprehensive income (loss)	75	(99)
Accumulated deficit	(2,058,298)	(1,578,926)
Total stockholders’ equity	995,204	1,032,276
Total liabilities and stockholders’ equity	$ 1,702,470	$ 1,642,075