Consolidated Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Current Assets:
Cash and cash equivalents	$ 41,135	$ 58,131
Marketable securities	265,744	224,625
Accounts receivable, net of reserves of $275 and $86 at December 31, 2015 and December 31, 2014	4,933	1,376
Inventory, net	6,677	4,017
Prepaid expenses and other current assets	7,641	3,528
Total current assets	326,130	291,677
Property and Equipment, at cost:
Laboratory equipment	12,786	10,381
Computer equipment and computer software	14,025	7,577
Assets under construction	8,038	1,552
Leasehold improvements	7,118	5,937
Buildings	4,777
Furniture and fixtures	1,265	939
Property and Equipment, gross	48,009	26,386
Less-Accumulated depreciation	(13,913)	(6,439)
Net property and equipment	34,096	19,947
Other long-term assets	4,070	1,200
Total assets	364,296	312,824
Current Liabilities:
Accounts payable	3,308	2,647
Accrued liabilities	22,253	13,960
Debt and capital lease obligation, current portion	166	360
Other short-term liabilities	996	554
Total current liabilities	26,723	17,521
Long-term debt	4,852	1,000
Long-term accrued interest		106
Other long-term liabilities	4,804	3,599
Lease incentive obligation, less current portion	1,061	1,614
Total liabilities	$ 37,440	$ 23,840
Commitments and contingencies (Note 8)
Stockholders' Equity:
Preferred stock, $0.01 par value Authorized—5,000,000 shares Issued and outstanding—no shares at December 31, 2015 and December 31, 2014
Common stock, $0.01 par value Authorized—200,000,000 shares Issued and outstanding—96,674,786 and 88,626,042 shares at December 31, 2015 and December 31, 2014	$ 968	$ 887
Additional paid-in capital	904,931	709,019
Accumulated other comprehensive loss	(433)	(115)
Accumulated deficit	(578,610)	(420,807)
Total stockholders' equity	326,856	288,984
Total liabilities and stockholders’ equity	$ 364,296	$ 312,824