CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Current assets:
Cash and cash equivalents	$ 167,714	$ 199,871
Marketable securities, short-term	359,581	254,787
Accounts receivable, net of allowance for doubtful accounts and returns of $2,472 and $1,563, respectively	158,550	129,751
Inventories	19,465	15,928
Prepaid expenses and other current assets	26,700	19,770
Deferred Tax Assets, Net, Current	0	37,053
Total current assets	732,010	657,160
Marketable securities, long-term	151,370	147,892
Property, plant and equipment, net	136,473	90,125
Goodwill	79,162	82,056
Deferred tax assets	51,416	3,099
Other assets	8,202	7,665
Total assets	1,158,633	987,997
Current liabilities:
Accounts payable	34,354	23,247
Accrued liabilities	107,765	87,880
Deferred revenues	129,553	90,684
Total current liabilities	271,672	201,811
Taxes Payable	37,512	30,483
Other long-term liabilities	1,523	2,932
Total liabilities	$ 310,707	$ 235,226
Commitments and contingencies (Notes 6 and 8)
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; 79,500 and 80,205 issued and outstanding at 2015 and 2014, respectively)	8	8
Additional paid-in capital	821,507	783,410
Accumulated other comprehensive income, net	(980)	(140)
Accumulated deficit	27,391	(30,507)
Total stockholders' equity	847,926	752,771
Total liabilities and stockholders' equity	$ 1,158,633	$ 987,997