CONDENSED CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Jun. 30, 2016	Dec. 31, 2015
Current assets:
Cash and cash equivalents	$ 167,706	$ 167,714
Marketable securities, short-term	404,107	359,581
Accounts receivable, net of allowances for doubtful accounts and returns of $3,128 and $2,472, respectively	192,660	158,550
Inventories	22,992	19,465
Prepaid expenses and other current assets	37,942	26,700
Total current assets	825,407	732,010
Marketable securities, long-term	113,158	151,370
Property, plant and equipment, net	161,685	136,473
Goodwill and intangible assets, net	83,749	79,162
Deferred tax assets	60,051	51,416
Other assets	7,223	8,202
Total assets	1,251,273	1,158,633
Current liabilities:
Accounts payable	30,927	34,354
Accrued liabilities	107,505	107,765
Deferred revenues	160,557	129,553
Total current liabilities	298,989	271,672
Taxes Payable	41,244	37,512
Other long-term liabilities	1,182	1,523
Total liabilities	341,415	310,707
Commitments and contingencies (Note 6 and 7)
Stockholders' equity:
Preferred stock, $0.0001 par value (5,000 shares authorized; none issued)	0	0
Common stock, $0.0001 par value (200,000 shares authorized; 79,868 and 79,500 issued and outstanding, respectively)	8	8
Additional paid-in capital	821,815	821,507
Accumulated other comprehensive income (loss), net	428	(980)
Retained earnings	87,607	27,391
Total stockholders’ equity	909,858	847,926
Total liabilities and stockholders’ equity	$ 1,251,273	$ 1,158,633