CONDENSED CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Mar. 31, 2017	Dec. 31, 2016
Current assets:
Cash and cash equivalents	$ 261,027	$ 389,275
Marketable securities, short-term	284,559	250,981
Accounts receivable, net of allowance for doubtful accounts and returns of $5,253 and $4,310, respectively	267,128	247,415
Inventories	35,174	27,131
Prepaid expenses and other current assets	70,279	38,176
Total current assets	918,167	952,978
Marketable securities, long-term	98,574	59,783
Property, plant and equipment, net	231,692	175,167
Equity method investments	43,940	45,061
Goodwill and intangible assets, net	92,447	81,998
Deferred tax assets	60,068	67,844
Other assets	14,405	13,320
Total assets	1,459,293	1,396,151
Current liabilities:
Accounts payable	37,028	28,596
Accrued liabilities	125,631	134,332
Deferred revenues	202,895	191,407
Total current liabilities	365,554	354,335
Income tax payable	46,322	45,133
Other long-term liabilities	2,542	1,294
Total liabilities	414,418	400,762
Commitments and contingencies (Note 8 and 9)
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; 80,324 and 79,553 issued and outstanding, respectively)	8	8
Additional paid-in capital	850,092	864,871
Accumulated other comprehensive income (loss), net	(1,382)	(938)
Retained earnings	196,157	131,448
Total stockholders’ equity	1,044,875	995,389
Total liabilities and stockholders’ equity	$ 1,459,293	$ 1,396,151