CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017
CASH FLOWS FROM OPERATING ACTIVITIES:
Net income	$ 302,843	$ 221,154
Adjustments to reconcile net income to net cash provided by operating activities:
Deferred taxes	2,047	(5,481)
Depreciation and amortization	38,185	26,715
Stock-based compensation	51,918	44,024
Equity in losses of investee	6,610	4,950
Other non-cash operating activities	11,363	9,432
Changes in assets and liabilities, net of effects of acquisitions:
Accounts receivable	(89,843)	(84,437)
Inventories	(17,192)	(10,709)
Prepaid expenses and other assets	(47,775)	(5,848)
Accounts payable	5,042	4,220
Accrued and other long-term liabilities	(25,436)	18,752
Long-term income tax payable	(18,435)	243
Deferred revenues	94,059	53,198
Net cash provided by operating activities	313,386	276,213
CASH FLOWS FROM INVESTING ACTIVITIES:
Acquisitions, net of cash acquired	0	(8,953)
Purchase of property, plant and equipment	(169,033)	(126,150)
Purchase of marketable securities	(150,022)	(356,928)
Proceeds from maturities of marketable securities	259,870	260,487
Purchases of investments in privately held companies	(5,000)	(12,764)
Proceeds from sales of marketable securities	9,560	32,291
Loan advances to equity investee	0	(23,000)
Loan repayment from equity investee	30,000	6,000
Other investing activities	604	(2,767)
Net cash used in investing activities	(24,021)	(231,784)
CASH FLOWS FROM FINANCING ACTIVITIES:
Proceeds from issuance of common stock	16,607	13,850
Common stock repurchases	(250,002)	(53,793)
Employees’ taxes paid upon the vesting of restricted stock units	(81,756)	(39,093)
Net cash used in financing activities	(315,151)	(79,036)
Effect of foreign exchange rate changes on cash, cash equivalents, and restricted cash	(2,890)	4,806
Net decrease in cash, cash equivalents, and restricted cash	(28,676)	(29,801)
Cash, cash equivalents, and restricted cash at beginning of the period	450,125	393,019
Cash, cash equivalents, and restricted cash at end of the period	421,449	363,218
SUPPLEMENTAL CASH FLOW INFORMATION:
Accounts payable or accrued liabilities related to property, plant and equipment	24,281	21,992
Conversion of convertible notes receivable into equity securities	$ 4,862	$ 0