CONDENSED CONSOLIDATED BALANCE SHEETS (Unaudited) - USD ($) $ in Thousands	Mar. 31, 2017	Dec. 31, 2016
Current assets:
Cash and cash equivalents	$ 114,221	$ 84,685
Short-term investments	746,060	580,538
Contracts receivable	69,357	108,043
Inventories	6,801	7,489
Other current assets	25,933	17,177
Total current assets	962,372	797,932
Property, plant and equipment, net	95,439	92,845
Patents, net	21,175	20,365
Deposits and other assets	5,010	1,325
Total assets	1,083,996	912,467
Current liabilities:
Accounts payable	23,237	21,120
Accrued compensation	8,267	24,186
Accrued liabilities	30,870	36,013
Current portion of long-term obligations	56	1,185
Current portion of deferred contract revenue	108,150	51,280
Total current liabilities	170,580	133,784
Long-term deferred contract revenue	115,759	91,198
1 percent convertible senior notes	508,411	500,511
Long-term obligations, less current portion	15,043	15,050
Long-term financing liability for leased facility	72,397	72,359
Total liabilities	882,190	812,902
Stockholders' equity:
Common stock, $0.001 par value; 300,000,000 shares authorized, 123,880,559 and 120,351,480 shares issued and outstanding at March 31, 2017 and December 31, 2016, respectively	124	122
Additional paid-in capital	1,410,102	1,311,229
Accumulated other comprehensive loss	(30,460)	(30,358)
Accumulated deficit	(1,177,960)	(1,181,428)
Total stockholders' equity	201,806	99,565
Total liabilities and stockholders' equity	$ 1,083,996	$ 912,467