CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016
CASH FLOWS FROM OPERATING ACTIVITIES:
Net income	$ 221,154	$ 142,061
Adjustments to reconcile net income to net cash provided by operating activities:
Deferred taxes	(5,481)	(17,476)
Depreciation and amortization	26,715	16,786
Stock-based compensation	44,024	39,934
Net tax benefits from stock-based awards	0	13,057
Excess tax benefit from share-based payment arrangements	0	(13,943)
Equity in losses of investee	4,950	477
Other non-cash operating activities	9,432	9,525
Changes in assets and liabilities, net of effects of acquisitions:
Accounts receivable	(84,437)	(93,122)
Inventories	(10,709)	(6,873)
Prepaid expenses and other assets	(5,848)	(5,069)
Accounts payable	4,220	(4,134)
Accrued and other long-term liabilities	18,995	38,969
Deferred revenues	53,198	46,482
Net cash provided by operating activities	276,213	166,674
CASH FLOWS FROM INVESTING ACTIVITIES:
Acquisitions, net of cash acquired	(8,953)	0
Purchase of property, plant and equipment	(126,150)	(56,368)
Purchase of marketable securities	(356,928)	(283,797)
Proceeds from maturities of marketable securities	260,487	328,498
Purchase of equity method investments	(12,764)	(46,745)
Proceeds from sales of marketable securities	32,291	209,302
Loan advances to equity investee	(23,000)	0
Loan repayment from equity investee	6,000	0
Other investing activities	397	(8,031)
Net cash provided by (used in) investing activities	(228,620)	142,859
CASH FLOWS FROM FINANCING ACTIVITIES:
Proceeds from issuance of common stock	13,850	12,877
Common stock repurchases	(53,793)	(58,174)
Excess tax benefit from share-based payment arrangements	0	13,943
Employees’ taxes paid upon the vesting of restricted stock units	(39,093)	(26,265)
Net cash used in financing activities	(79,036)	(57,619)
Effect of foreign exchange rate changes on cash and cash equivalents	4,781	320
Net increase (decrease) in cash and cash equivalents	(26,662)	252,234
Cash and cash equivalents, beginning of the period	389,275	167,714
Cash and cash equivalents, end of the period	362,613	419,948
SUPPLEMENTAL CASH FLOW INFORMATION:
Accounts payable or accrued liabilities related to property, plant and equipment	$ 21,992	$ 9,709