CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOW (USD $) In Thousands, unless otherwise specified	6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013
Cash flow from operating activities:
Net income	$ 336,219	$ 308,481
Adjustments to reconcile net income to cash provided by operating activities:
Depreciation and amortization	77,618	66,762
Stock-based compensation expense	19,249	17,175
Excess tax benefits from stock-based compensation payment arrangements	(18,103)	(16,023)
Net change in components of working capital	(41,254)	(26,727)
Net change in other long-term assets and liabilities	9,611	11,138
Net cash provided by operating activities	383,340	360,806
Cash from investing activities:
Additions to property, plant and equipment	(105,910)	(66,037)
Proceeds from disposal of fixed assets	1,351	1,412
Purchases of short-term investments	(356,032)	(408,845)
Sales and maturities of short-term investments	293,405	241,605
Acquisitions, net of cash acquired	(19,467)	(44,036)
Net cash used in investing activities	(186,653)	(275,901)
Cash from financing activities:
Issuance of senior notes	748,846
Borrowings under credit facilities	398,100	302,583
Repayments under credit facilities	(936,593)	(225,842)
Payments of fees and expenses related to debt financing	(5,751)
Proceeds from exercise of stock options	58,286	64,204
Excess tax benefits from stock-based compensation payment arrangements	18,103	16,023
Payments to shareholders of non-controlling interests	(1,729)	(1,736)
Purchase and retirement of treasury stock	(250,159)	(181,108)
Dividend payments	(31,418)	(16,756)
Net cash used in financing activities	(2,315)	(42,632)
Effect of exchange rate changes on cash and cash equivalents	(1,127)	(9,464)
Net change in cash and cash equivalents	193,245	32,809
Cash and cash equivalents balance, beginning of period	886,838	690,850
Cash and cash equivalents balance, end of period	1,080,083	723,659
Cash paid for:
Interest	29,737	29,737
Income taxes	$ 119,332	$ 82,639