Condensed Consolidated Balance Sheets - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Current assets:
Cash and cash equivalents	$ 209,702	$ 599,691
Short-term investments	583,158	479,369
Accounts receivable	48,601	29,468
Inventory	115,816	83,605
Other current assets	54,800	36,511
Total current assets	1,012,077	1,228,644
Property and equipment, net of accumulated depreciation of $25,224 and $18,022 as of September 30, 2018, and December 31, 2017, respectively	76,841	43,156
Intangible assets, net of accumulated amortization of $5,532 and $4,145 as of September 30, 2018, and December 31, 2017, respectively	15,324	14,355
Other assets	78,664	21,809
Total assets	1,182,906	1,307,964
Current liabilities:
Accounts payable	20,408	8,467
Accrued expenses	88,687	68,982
Current portion of long-term debt		6,175
Deferred revenue	3,303	3,316
Other current liabilities	1,995	1,392
Total current liabilities	114,393	88,332
Long-term debt	415,446	424,876
Deferred rent and other	13,219	5,539
Total liabilities	543,058	518,747
Commitments and contingencies (Note 16)
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; 66,693,348 and 64,791,670 issued and outstanding at September 30, 2018, and December 31, 2017, respectively	7	6
Additional paid-in capital	2,077,864	2,006,598
Accumulated other comprehensive income (loss)	8	(379)
Accumulated deficit	(1,438,031)	(1,217,008)
Total stockholders’ equity	639,848	789,217
Total liabilities and stockholders’ equity	$ 1,182,906	$ 1,307,964