CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOW (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2014	Mar. 31, 2013
Cash from operating activities:
Net income	$ 159,802	$ 153,613
Adjustments to reconcile net income to cash provided by operating activities:
Depreciation and amortization	39,873	32,592
Stock-based compensation expense	9,276	8,283
Excess tax benefits from stock-based compensation payment arrangements	(2,652)	(8,720)
Net change in components of working capital	(10,197)	(12,135)
Net change in other long-term assets and liabilities	6,557	6,621
Net cash provided by operating activities	202,659	180,254
Cash from investing activities:
Additions to property, plant and equipment	(54,176)	(29,685)
Proceeds from disposals of fixed assets	538	802
Purchases of short-term investments	(120,728)	(110,744)
Sales and maturities of short-term investments	144,951	75,488
Acquisitions, net of cash acquired	(8,978)	201
Net cash used in investing activities	(38,393)	(63,938)
Cash from financing activities:
Issuance of senior notes	748,846
Borrowings under credit facilities	142,800	101,300
Repayments under credit facilities	(801,074)	(119,215)
Payments of fees and expenses related to debt financing	(5,750)
Proceeds from exercise of stock options	13,724	30,682
Excess tax benefits from stock-based compensation payment arrangements	2,652	8,720
Payments to shareholders of noncontrolling interests	(1,052)	(1,247)
Purchase and retirement of treasury stock	(121,130)	(85,300)
Net cash used in financing activities	(20,984)	(65,060)
Effect of exchange rate changes on cash and cash equivalents	(6,800)	(7,113)
Net change in cash and cash equivalents	136,482	44,143
Cash and cash equivalents balance, beginning of period	886,838	690,850
Cash and cash equivalents balance, end of period	1,023,320	734,993
Cash paid for:
Interest	13,327	12,740
Income taxes	$ 48,827	$ 38,852